AsCA 2018 / CRYSTAL 32

ORAL ABSTRACT BOOK

24/11/2018

PLENARIES

Amyloid Fibrils in Health and Disease David S. Eisenberg, Michael P. Hughes, Michael Sawaya, Qin Cao, David Boyer, Paul Seidler, Elizabeth Guenther, Jose Rodriguez, Duilio Cascio, Tamir Gonen Howard Hughes Medical Institute, UCLA UCLA-DOE Institute, Departments of Biological Chemistry & Chemistry & Biochemistry

Some 50 fatal human diseases are all associated with the presence in tissues of fibrils with similar properties, termed amyloid fibrils. The most prevalent of these diseases are Alzheimer’s and diabetes type 2. Others include Parkinson’s, ALS, and senile amyloidosis. In some of these conditions, fibrils are found in the brain and cause the gradual death of neurons, leading to dementia. In others, fibrils are found throughout the body, often accumulating in the heart and other organs, eventually causing organ failure.

We have investigated the structures of these pathogenic fibrils, using the tools of x-ray and electron diffraction, and cryo-electron microscopy. We find that these pathogenic fibrils are formed by stacks of proteins into beta sheets, with pairs of these sheets forming tightly bonding structures that we term steric zippers.

Related ‘amyloid-like’ fibrils are formed by proteins that participate in the formation of transient intracellular bodies, a phenomenon termed liquid-liquid phase separation. These amyloid like fibrils are reversible, unlike the extremely stable pathogenic amyloid fibrils. Proteins that form these reversible fibrils contain low-complexity domains, with a high proportion of Gly, Ser, Tyr, Phe, and Gln residues. We term the protein segments that form such reversible segments LARKS, for Low-complexity, Amyloid-like, Reversible, Kinked Segments.

Adventures in Diffraction: Probing Dynamic Processes within Molecular Framework Materials Kepert, Cameron The University of Sydney, Camperdown NSW 2006, Australia

Over recent years the design and synthesis of molecular framework materials has seen the emergence of a rich array of novel host-guest, mechanical and electronic/magnetic properties. Accompanying this progress has been a range of opportunities and challenges for the structural scientist, requiring the use of diffraction methods that probe structural change in response to temperature, pressure, gas/vapour pressure, chemical reagents and light irradiation. In this talk I will describe some of my research group’s contributions in this area, with specific focus on our exploration of three interesting and useful properties.

Nanoporosity. The linkage of metal ions with multitopic ligands generates robust open lattices that are able to act as hosts for a wide range of molecular guests, some of which may be comparatively innocent in having negligible impact on framework structure, and some of which may drive pronounced perturbation, both geometric and chemical.

Anomalous thermomechanical behaviours. The comparatively low energies associated with the deformation of molecular lattices – a property that emerges both from the flexibility of their building units and from their underconstrained topologies – has led to the emergence of a rich array of novel mechnical properties. Thermal excitation of transverse molecular vibrations within these materials has yielded unprecedented negative thermal expansion (NTE; i.e., contraction upon warming), which can be moderated through control of both the framework and host-guest chemistry. Additionally, their low energy deformation can occur under high pressure to yield extreme mechanical behaviours, as seen in the achievement of unprecedented compressibilities (see Figure).

Cooperative electronic transitions. The incorporation of spin-crossover centres into nanoporous molecular frameworks has led to the first porous materials that can be switched between multiple electronic states, and to some interesting structural challenges in unlocking the subtle cooperative effects that stabilise complex lattice patterning in mixed spin-state systems.

Bacterial Protein Export Machines Lea, Susan1 1Sir William Dunn School of Pathology and Central Oxford Structural Molecular Imaging Centre, Univeristy of Oxford, UK

Secretion of proteins into the environment is a fundamental feature of bacterial life. This mechanism allows pathogenic bacteria to cause disease both by secretion of toxins and also by assembling the secreted proteins to form the nano-machines required for motility. Many important human pathogens use either type 3 or type 9 secretion systems, T3SS or T9SS for short, to perform these functions with deletion of the secretion system rendering the bacteria non-pathogenic. The T3SS is particularly important for eight of the twelve bacterial families highlighted by the World Health Organisation as those for which we critically need to develop novel antibiotics due to their world-wide disease burden. We are using a range of structural methodologies to study both bacterial systems and will present recent work describing novel structures from these complex bacterial nano-machines.

SCANZ AWARDS:

1987 PLENARY LECTURE - Amy C. Rosenzweig

BRAGG MEDAL - J. Mitchell Guss

MATHIESON MEDAL - Suzanne Neville

Biological methane oxidation Amy C. Rosenzweig Departments of Molecular Biosciences and of Chemistry, Northwestern University, Evanston, IL 60208, USA

Methanotrophic bacteria oxidize methane to methanol in the first step of their metabolic pathway. Whereas current catalysts that can selectively activate the 105 kcal mol-1 C-H bond in methane require high temperatures and pressures, methanotrophs perform this chemistry under ambient conditions using methane monooxygenase (MMO) enzymes. In most methanotrophs, this chemically challenging reaction is catalyzed by particulate methane monooxygenase (pMMO), a copper-dependent, integral membrane enzyme. pMMO is composed of three subunits, PmoA, PmoB, and PmoC, arranged in a trimeric complex. Despite extensive research and the availability of multiple crystal structures, the location and nature of the pMMO copper active site remain controversial and the details of dioxygen activation and methane oxidation have not been elucidated. Studies are further complicated by issues with retaining enzymatic activity and uncertainties regarding the identity of the native reductant and the possible involvement of additional protein components. Progress toward addressing these key questions will be reported.

Figure 1. Crystal structure of particulate methane monooxygenase

My life in crystallography Guss, J. Mitchell1 1School of Life and Environmental Sciences, University of Sydney, NSW 2006, Australia

In this talk I will follow the trail of my life for the past 54 years building a research career that sought to solve chemical and biochemical problems using the tools of X-ray diffraction, including crystallography, fibre diffraction and small angle scattering. In the course of this journey I shall highlight the chance events that led to what might otherwise in retrospect be seen to be seen as a carefully planned career. I have been lucky to live and work in a number of different countries and had the chance to make lifelong friendships along the way.

Molecular Switching Framework Materials

Suzanne M Neville

School of Chemistry, UNSW, Sydney, Australia s.neville@unsw.edu.au

Porous coordination polymers (PCPs) are a characteristic example of materials with highly crystalline, soft and tuneable porous architectures. In ‘third generation’ PCPs, synergistic framework transformations occur in response to molecular guests resulting in guest-switchable bistability and can lead to emergent porous properties. Due to the strong coupling between the host lattice and guest, other physical attributes (such as electron transfer and spin-state) can be perturbed in parallel with PCP flexing, thereby instilling advanced capabilities in these multi-functioning PCPs. Our research focuses on exploiting the structural and design flexibility of PCPs to tailor the transition pathway and characteristics of the spin crossover effect (SCO). By this approach we have produced a diverse range of cooperative, guest-modulated, multi-stepped, ambient and emergent switching properties in SCO-PCPs.1-6 Structure-function analysis is integral to these studies and has revealed new features about how elastic versus elastic frustration globally impacts the SCO phenomenon.

[1] S. M. Neville et al., Angew. Chem., Int Ed. 2007, 46, 2059; [2] S. M. Neville et al. J. Am. Chem. Soc., 2009, 131, 12106; [3] Y. M. Klein et al. Chem. Comm. 2014, 50, 3838-3840; [4] M. J. Murphy et al., J. Am. Chem. Soc. 2017, 139, 1330-1335; [5] N. F. Sciortino, Chem. Sci. 2017, 8, 701-707; [6] K. A. Zenere et al., Chem. Sci., 2018, 9, 5623-5629.

KEYNOTES

Harnessing Electroactivity in Coordination Frameworks D’Alessandro, Deanna M.1 1School of Chemistry, The University of Sydney, NSW, Australia 2006

Electroactive coordination frameworks (aka Metal-Organic Frameworks (MOFs)) offer a fundamental platform to explore electron transfer phenomena within 3-dimensional coordination space.1 At the applied level, these materials have enormous potential as the basis for electrochromic devices, electrocatalysts, porous conductors, batteries and solar energy harvesting systems, amongst numerous other potential applications.2,3

This presentation will detail our latest results in the design and synthesis of electroactive frameworks that integrate molecular components for electron transfer including radical ligands and mixed-valence centres. The insights gained into fundamental charge transfer phenomena of relevance to understanding biological photosynthetic systems and porous semiconductors will be discussed. Key to our investigations have been solid-state AC/DC electrochemical methods in addition to solid-state near-IR/Vis, EPR, FT-infrared and Raman

spectroelectrochemical (SEC) techniques that have been developed in our laboratory, providing powerful in situ probes for the optical and electron transfer characteristics of MOFs. These methods are potentially relevant to exploring electroactivity and fundamental charge transfer phenomena in a wide range of other materials (e.g., supramolecular systems, battery materials, etc). Our work on the DFT computational modelling of the electronic and optical properties of these systems will also be described, providing an important link between experiment and theory.

Figure.1. The framework [Zn2(TTFTB)(H2O)2] (TTFTB = tetrathiafulvalene tetrabenzoate) exhibits through-space mixed valency due the presence of TTF in a mix of its radical cation and neutral states.

Building chains: regulation of ubiquitin transfer by E3 ligases Day, Catherine1 Biochemistry Department, University of Otago, Dunedin, New Zealand.

Eukaryotic cell phenotype and function relies on the exquisite control of cell signaling pathways. Protein-protein interactions have a central role in these pathways and they are often regulated by the post translational modification of proteins. One pervasive post-translational modification that plays a key role in regulating the logic of many signalling pathways is the attachment of ubiquitin to proteins. Protein ubiquitylation can alter protein function and abundance, which together can determine if signals are transmitted.

Ubiquitin E3 ligases mediate transfer of ubiquitin to substrate proteins and are responsible for both activation of the E2 ubiquitin conjugating enzyme and for substrate recruitment. Many E3 ligases are defined by the presence of a RING domain that binds the E2 and promotes ubiquitin transfer. Research in my laboratory is focused on understanding how the E3 ligase activity of RING domains is regulated. In this talk I will describe our molecular analysis of several different RING-E3 ligases that have essential roles in regulating cell survival. I will also highlight the implications of these discoveries for the regulation of cell signalling.

Toward dimensional crossover on conductive coordination networks Kitagawa, Hiroshi Division of Chemistry, Graduate School of Science, Kyoto University

More than 25 years, I have investigated MX or MMX chains system as a model of pure 1-D electron system, because this system has wide variety of possible electronic phases [1-2]. The MMX chain is composed of M-M dimer and bridging iodine. In this system, there are four dominant interactions, transfer integral t, on-site Coulombic repulsion U, nearest neighbor Coulombic repulsion V, and electron-lattice interaction S, those are competing to each other in energy. The charge-ordering states with lattice distortions of a halogen-bridged binuclear-metal mixed-valence complex (called MMX chain), Pt2(L)4I (L = CH3CS2

- and C2H5CS2-),

have been investigated by transport, magnetic, and optical measurements. This complexes are binuclear unit-assembled conductor containing metal−metal bonds. It exhibits a metallic conduction, representing the first example of a metallic halogen-bridged one-dimensional transition-metal complex. At low temperature, it shows semiconducting behavior, which is consid-ered to be of the Mott−Hubbard type due to elec-tron correlation. The metal−semiconductor transi-tion (TM-S) is derived from a valence transition of Pt from an averaged-valence state of 2.5+ to a trapped-valence state of 2+ and 3+. The charge-ordering modes are considered to be mode (c) for the semiconducting phase below TM-S and mode (a) for the metallic phase above TM-S. 129I Möss-bauer spectroscopic study is reported for a low-temperature insulating phase below 80 K. The low-temperature electronic structure is consid-ered to be an alternate charge-ordering state with lattice distortions of mode (d). The present binu-clear platinum complex inherently possesses va-lence instability of the intermediate valence 2.5+. The vibronic state in the intermediate phase is also discussed. Conductive MOF nanotube is also presented [3-5].

Reference: [1] H. Kitagawa, et al., J. Am. Chem. Soc., 121, 10068 (1999), J. Am. Chem. Soc., 121, 2321 (1999), Coord.

Chem. Rev., 190, 1169 (1999), J. Am. Chem. Soc., 123, 11179 (2001), Angew. Chem. Int. Ed., 41, 2767, (2002), J. Am. Chem. Soc., 126, 1614 (2004), J. Am. Chem. Soc., 128, 6676 (2006), J. Am. Chem. Soc., 128, 8140 (2006), J. Am. Chem. Soc., 128, 12066 (2006), Chem. Asian J., 4, 1673 (2009), CrystEngComm, 16 6277-6286 (2014), Inorg. Chem., 53, 1229 (2014), Eur. J. Inorg. Chem., 4402-4407 (2016), Inorg. Chem., 55, 2620 (2016), Nature Commun., 7, 11950 (2016), Angew. Chem. Int. Ed., 56, 3838 (2017).

[2] T. Yamada, K. Otsubo, R. Makiura, H. Kitagawa, Chemical Society Reviews, 42, 6655 (2017). [3] K. Otsubo, Y. Wakabayashi, J. Ohara, S. Yamamoto, H. Matsuzaki, H. Okamoto, K. Nitta, T. Uruga, H. Kitagawa,

Nature Materials, 10, 291 (2011). [4] S. Sakaida, K. Otsubo, O. Sakata, C. Song, A. Fujiwara, M. Takata, H. Kitagawa, Nature Chemistry, 8, 377 (2016). [5] K. Otake, K. Otsubo, K. Sugimoto, A. Fujiwara, H. Kitagawa, Angew. Chem. Int. Ed., 55, 6448 (2016).

Figure. Electronic phases in MMX chain.

Time-resolved diffraction experiments at X-ray free electron lasers reveal ultrafast structural changes in photosynthesis

Rob Dods1, Petra Båth1, David Arnlund1, Cecilia Wickstrand1, Linda Johansson1, Anton Barty2, Kenneth Beyerlein2, Henry Chapman2, Sebastian Boutet3, Daniel dePonte3, Garrett Nelson4, John Spence4, Antoine Royant5, Richard Neutze1 1University of Gothenburg, Sweden. 2CFEL, DESY, Germany. 3LCLS, USA. 4Arizona State University, USA. 5ESRF, France.

X-ray free electron lasers (XFEL) provided a billion-fold jump in the peak X-ray brilliance when compared with synchrotron radiation. This technical advance created completely new experimental approaches to time-resolved protein crystallography and allowed structural studies of protein conformational changes on ultrafast time-scales. I will discuss the key ideas underlying the application of XFEL radiation for structural studies of biomolecules and describe how we have used time resolved serial femtosecond crystallography at an XFEL to probe light-driven structural changes in a bacterial photosynthetic reaction centre. The photosynthetic reaction centre of Bl. Viridis is an integral membrane protein that harvests sunlight to pump protons. Proton transport is achieved through the movement of electrons across the cell membrane and these electron movements are coupled to redox reactions. Time resolved diffraction studies at the LCLS, the world’s first XFEL at Stanford, revealed structural changes on the picosecond time-scale near the special pair (which is photo-oxidized following the absorption of a photon) and the tightly bound menaquinone (which is reduced by the movement of an electron from the special pair). These structural results provide new chemical insight into how protein structural dynamics optimize how the energy of sunlight is directed into the biosphere.

Capturing a protein reaction triggered by laser photolysis in crystals. Sato-Tomita, Ayana1 1Division of Biophysics, Jichi Medical University

Today, X-ray crystallography is the most common and powerful technique to determine protein structures at the atomic level. However, its static structures do not tell us much about the protein’s reaction pathway. Thus, it is very important to solve the protein structures of reaction intermediate to understand the essential point of its function. Here, two kinds of techniques are introduced to capture a photolysis intermediate of hemeproteins, CO-bound myoglobin, and hemoglobin. The first method is time-resolved X-ray crystallography combined with high-repetition pulsed-laser pumping and cryogenic trapping. The second method is pump-probe X-ray crystallography using pulsed laser and pulsed X-ray of synchrotron radiation. At cryogenic temperatures under 50 K, a photo-dissociated ligand (CO) molecule can move to only the limited range near the heme, and the protein moiety can undergo only small structural changes. By contrast, at 100-140 K under continuous pulsed-laser irradiation, the ligand migration and protein relaxation can be observed. Around room temperature, we can carry out a real-time measurement to obtain a protein reaction.

CRISPR-Cas Mediated Cleavage of Invading Nucleic

Acids

Liu Liang 1, Li Jiazhi1,2, Wang Jiuyu1, Ma Jun3, Wang Min1, Li Xueyan1,2, Zhang Xinzheng3 and Wang Yanli1

1Key Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China 2University of Chinese Academy of Sciences, Beijing 100049, China 3National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.

Bacteria and archaea are protected against invading nucleic acids from phages and plasmids because of CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)-Cas (CRISPR associated proteins) systems, which are RNA-guided prokaryotic adaptive immune system. CRISPR-Cas systems are found in nearly half of all bacteria studied so far, as well as in the majority of archaea. However, throughout evolution, this host defense system has not resulted in the eradication of phages, suggesting that phages have evolved counter strategies to thrive within bacteria despite these mechanisms. Thus, both bacterial CRISPR system and phage anti-CRISPR system are part of a continuing evolutionary battle between bacterial host and their bacteriophage invaders. We provided significant insights into the molecular mechanism for how CRISPR-Cas systems defend against the invading nucleic acids from phages and how phages counteract the CRISPR-Cas systems by anti-CRIPR proteins.

RISING STAR SESSION

Microcrystallography of heterogenous in vivo-grown protein crystals from the viviparous cockroach Diploptera punctata Sanchari Banerjeea$, Nathan P. Coussensbc$, François-Xavier Gallat, Nitish Sathyanarayanan, Jandhyam Srikanth, Koichiro J. Yagi, James S.S. Gray, Stephen

S. Tobe, Barbara Stay, Leonard M.G. Chavasd and Subramanian Ramaswamyab

aInstitute of Stem Cell Biology and Regenerative Medicine, Bangalore, India, bDepartment of Biochemistry, Carver College of Medicine, University of Iowa, Iowa City, USA, cNational Center for Advancing Translational Sciences, National Institutes of Health, USA, iExperimental Division, Synchrotron SOLEIL, Gif-sur-Yvette, France $Equal Contribution

In vivo protein crystallization is the natural process whereby positive natural selection pressure allows a subset of proteins with functional significance to crystallize inside an organism (in cellulo/ex cellulo). These naturally occurring in vivo protein crystals perform a diversity of functions like food storage, defence etc. Their small sizes make them unsuitable for protein structure determination using conventional X-ray crystallography. Microcrystallography refers to the specific approaches developed for structure determination using such microcrystals. My work focuses on the microcrystals from the only known viviparous cockroach, Diploptera punctata. The pregnant mothers provide nourishment to the developing embryos inside its brood sac in the form of milk proteins. The excess milk ingested by the embryos is stored in crystalline form for future use. These in vivo-grown milk protein crystals were isolated for structural and other biophysical studies. The structure was determined at an atomic resolution of 1.2 Å by anomalous dispersion from the native S atoms. Structure determination has also been attempted by serial femtosecond crystallography using data collected at SACLA, Japan. The structure reveals presence of glycosylated proteins that adopt a lipocalin fold, bind lipids and organize to form a tightly packed crystalline lattice. A single crystal is estimated to contain ~3X more energy of an equivalent mass of mammalian milk. To the best of our knowledge, this is the first and only structure, which is highly heterogeneous with respect to amino-acid sequence, glycosylation and bound fatty-acid composition, yet crystallizes readily and diffracts to atomic resolution.

Figure.1. The X-ray crystal structure of in vivo milk proteins from Diploptera punctata. Inset: The in vivo-grown crystals inside the embryos.

Charge density study of diamond at 800K using data correctionfor weak intensities.Deguchi, Yuka1; Nishibori, Eiji1,2

1 Graduate School of Pure and Applied Sciences, University of Tsukuba, Japan2 Faculty of Pure and Applied Sciences and Tsukuba Research Center for Energy MaterialsScience, University of Tsukuba, Japan

Properties of a material are changed by the thermal effects. Lattice expansion, conductivitychange, and heat capacity change, etc. of materials are observed with increasing thetemperature. Temperature dependences of the charge density should provide a knowledgeof the thermal effect on the property of the material. An X-ray charge density studygenerally requires the highly accurate and reliable data covered by a wide reciprocal space.The diffraction data measured at low temperature have been usually used for the chargedensity study because of the higher Bragg intensities in high angle region. The chargedensity study under the sufficient high temperature condition has never been carried out sofar by a full-parameter multipole refinement owing to unavailability of the high reciprocalresolution data. In this study, we determined structure factors at 800K with sinθ/λ < 2.2 Å-1

of diamond for the charge density study from the multiple overlaid powder profilesmeasured at SPring-8 BL02B2 beamline. We found a systematic noise in the data. Datacorrection of the noise was essential to extract Bragg intensities of weak reflections. Aquality of the data was evaluated by the charge density study using the multipolerefinement and topological analysis. The reliability factors and multipole parametersdetermined at 800K were almost comparable to those of room temperature (RT) data. Thetopological measures at 800K were also comparable to those of RT.

Figure.1. Powder profiles of the corrected (purple line) and uncorrected (green line) data are shown.

Lactate racemization, a story of so much more than just a nickelFellner, Matthias1,2; Desguin, Benoît3; Rankin, Joel2; Hausinger, Robert2; Hu, Jian2

1Department of Biochemistry, University of Otago, Dunedin, NZ2Department of Biochemistry and Molecular Genetics, Michigan State University, EastLansing, USA3Institute of Life Sciences, Université catholique de Louvain, Louvain-La-Neuve, Belgium.

Lactate racemase LarA, the ninth discovered nickel-dependent enzyme, was shown tocontain a newly identified vitamin B3 derived nickel pincer nucleotide cofactor. Synthesis ofthe cofactor involves three proteins LarB, LarE, and LarC.

Cofactor biosynthesis begins with LarB, a carboxylase/hydrolase of NaAD. LarE, a newmember of the PP-loop ATP Pyrophosphatase family, then inserts two sulfur atoms.Structural analysis, combined with structure-guided mutagenesis establishes LarE as aparadigm for sulfur transfer through sacrificing its catalytic cysteine residue, only thesecond sacrificial sulfur transferase to be described.

Finally, LarC inserts a nickel atom to form a five-membered nickellacycle structure in whicha stable nickel-carbon bond, as well a nickel-sulfur bond is created (a metallacycle). LarC istherefore the first cylometallase identified in nature. Structure-function characterizationdiscovered that LarC requires cytidine triphosphate hydrolysis.

LarA then utilizes the cofactor for lactate racemization. Again using functional and structuralmethods we provided compelling evidence, that this is accomplished via a proton-coupledhydride transfer mechanism.

Lactate racemization is involved in lactate metabolism and cell wall assembly but thecofactor may also be used for a wide range of other yet to be discovered reactions.

Figure.1. Lactate racemase, the 9th nickel enzyme to ever be discovered.

Structural basis for importin alpha 3 specificity of W proteins inHendra and Nipah virusesKate M. Smith1,+, Sofiya Tsimbalyuk1,+, Megan R. Edwards2,+, Emily M. Cross1, Jyoti Batra2,Tatiana P. Soares da Costa3, David Aragão4, Christopher F. Basler2,*, Jade K. Forwood1,*

+ Equal contribution

* Joint senior/corresponding authors

1School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, New SouthWales, 2678, Australia

2Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia StateUniversity, Atlanta, GA 30303, USA. Electronic address: cbasler@gsu.edu.

3Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, LaTrobe University, Melbourne, Victoria 3086, Australia

4Australian Synchrotron, Australian Nuclear Science and Technology Organisation, 800Blackburn Road, Clayton, Victoria 3168, Australia

Seven human isoforms of importin α mediate nuclear import of cargo in a tissue- andisoform-specific manner. Understanding how nuclear import adaptors differentially interactwith cargo harbouring the same NLS remains poorly understood since the NLS recognitionregion is highly conserved. Here, we provide a structural basis for the nuclear importspecificity of W proteins in Hendra virus (HeV) and Nipah virus (NiV). We determine thestructural interfaces of these cargo and importin α1 and α3, identifying a 2.4-fold moreextensive interface and >50-fold binding affinity for importin α3. Through the design ofimportin α1 and α3 chimeric and mutant proteins, together with structures of cargo-freeimportin α1 and α3 isoforms, we establish that the molecular basis of specificity resides inthe differential positioning of the armadillo-repeats 7 and 8. Overall, our study providesmechanistic insights into a range of important nucleocytoplasmic transport processes relianton isoform adaptor specificity.

Noncovalent Carbon Bonding: Is it a σ-hole interaction of broad implications? Naseer, Muhammad Moazzam Department of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan

While noncovalent interactions such as hydrogen[1] and halogen[2] bonds are now well established and characterized through both experimental and computational methods, the recent surge of interest in controlling the molecular organization in the solid state (crystal enginneering) as well as in solution (self-assembly) has directed the researchers to recognize increasingly the importance of weak non-covalent interactions. Non-covalent interactions such as C-H···O and C-H···π which were initially considered weak have now become a well-accepted axiom.

Carbon-bonding is a recently explored non-covalent σ-hole interaction which was first highlighted by Mani and Arunan through theoretical calculations on the Ar···propargyl alcohol complex[3a] and later experimentally substantiated by Guru Row and co-workers through X-ray charge density analysis.[4b] Although, this interaction was proposed to be a realistic interaction with broad implications in supramolecular chemistry, but so far it is primarily researched as a structure guided interaction. In view of our recent interest in noncovalent carbon bonding,[4]. we disclose and describe its role in the intramolecular stabilization of cis-conformation of amide moiety in acylhydrazones both by experiment and theory (Figure 1). With these results, it can safely be concluded that the carbon bonding although is a weak but not mere a structure-guided interaction. Surely it is an interaction of broad implications in crystal engineering, host-guest and related fields of supramolecular chemistry.

Figure.1. Cis-trans conformations in semicarbazones and acylhydrazones, highlighting stabilizing role of H-bonding and carbon bonding in preferable cis conformations References: [1] G. R. Desiraju, Acc. Chem. Res. 2002, 35, 565–573. [2] P. Metrangolo, F. Meyer, T. Pilati, G. Resnati, G. Terraneo, Angew. Chem., Int. Ed. 2008, 47, 6114–6127. [3] a) D. Mani, E. Arunan, Phys. Chem. Chem. Phys. 2013, 15, 14377–14383; b) S. P. Thomas, M. S. Pavan, T. N. G. Row, Chem. Commun., 2014, 50, 49–51; [4] (a) M. Hussain, A. Bauzá, A. Frontera, K. M. Lo, M. M. Naseer, CrystEngComm, 2018, 20, 150-154; (b) R. Jawaria, M. Hussain, Z. Shafiq, H. B. Ahmad, M. N. Tahir, H. A. Shad, M. M. Naseer, CrystEngComm, 2015, 17, 2553-2561.

A Spin Crossover Framework That Does It AllZenere, Katrina1; Neville, Suzanne2; Kepert, Cameron1

1School of Chemistry, The University of Sydney, Australia2School of Chemistry, The University of New South Wales, Australia

Spin crossover (SCO) is a phenomenon where a 3d4–7 metal ion can reversibly switch

between a high spin (HS) and low spin (LS) state upon an external perturbation (such as

temperature, pressure, light irradiation, or guest exchange). One of the most exciting

behaviours observed in these materials is the possibility of a bistable ‘memory’ effect, in

which the material can exist in both the HS and LS states under the same conditions. For

example, some materials have exhibited spin state switching at a single temperature using

light of specific wavelengths, the application of increasing pressure can induce a HS to LS

transition, and guest exchange has been demonstrated to dramatically influence SCO

behaviour within the one host material (particularly in porous systems). Notably,

cooperative SCO behaviour in solid state systems arises through inelastic interactions

between the SCO sites, which propagate communication of spin state throughout the

material, typically resulting in abrupt, hysteretic, and room temperature spin transitions.

Such SCO behaviour has great promise for applications in, for example, data storage and

molecular sensing devices.

My research focuses on incorporating 1,2,4-triazole functionalised ligands into porous 2D

Hofmann-type framework materials (Figure 1). Previously in our research group, such

materials have been found to exhibit interesting (and even rare) SCO behaviours. This

work will explore one such framework material that exhibits a diverse range of SCO

behaviours with temperature variation, pressure application, light irradiation, and guest

manipulation. Through exploring the consequences of spin state switching under multiple

conditions using various techniques, we have developed a thorough fundamental

understanding of the structure–function relationship of SCO materials, which is critical in

the pursuit of rational design of functional devices.

Figure 1. 2D Hofmann-type framework for spin crossover with multiple stimuli.

GENERAL INTEREST SESSION

History of crystallography as viewed through the lens of the Nobel Prize Liljas Anders Department of Biochemistry and Structural Biology Lund University Crystals has for ages been of great fascination for mankind. From the early part of last century crystallography developed into a science that gave us unique insight into how matter is organized. Early heroes like Wilhelm Conrad Röntgen, Max von Laue and William Henry and William Lawrence Bragg took the first important steps that led to a landslide of discoveries. They were all honored by Nobel Prizes. It is no surprise that a long line of subsequent crystallographers have also been awarded Nobel Prizes since the insights obtained have been of fundamental nature. The presentation will give some details of the early work in the Nobel committees as well as a review of the long list of Nobel laureates that have used crystallography as their main method.

Figure 1. The first protein structure in the form of structure factors on paper tapes carried to the computer by Richard Dickerson and Bror Strandberg 1959.

Piotrek Sliz – Abstract to come

The role of Cryo-electron microscopy in structural biology after the“resolution revolution”.

Marc Storms, Alevtyna Yakushevska, Kristian Wadel, Gabriella Kiss, Steve ReyntjensThermo Fisher Scientific, MSD, Achtseweg Noord 5651 GG Eindhoven

During the last few years Cryo-EM and SPA have grown from techniques able to produce low-

resolution structures of protein complexes to tools capable of achieving atomic and quasi-

atomic resolution for complexes that nobody could solve with any other technique.

This incredible leap forward has been made possible by introduction and adoption of new

tools, in particular direct electron detectors (DED), ultra-stable cryo-microscopes, such as Titan

Krios, and the adoption of new SW for automatic data collection and processing.

Cryo-EM benefits from specific advantages, respect to other structural biology techniques such

as NMR and X-ray diffraction:

Crystallization or isotopic labelling is not needed.

Amount of sample required is two orders of magnitude lower.

Different functional conformation of a complex may be sorted out.

Cryo-EM has proved to be a very useful technique to be integrated with X-ray and NMR for

structure-based drug design.

In this presentation we will see how the fast pace of cryo-EM growth is going to change the

structural biology landscape for the best.

In particular we will discuss the:

Glacios™ Cryo-TEM: A 200kV X-FEG autoloader-provided system capable of

automatic screening of multiple grids and reduced footprint.

The new KriosTM G3i: The latest Krios version with improved automation, increased

cryo-performance and higher throughput.

The new development of mED (micro Electron Diffraction): a technology that holds the

promise to solve at high resolution, structures of crystals so small that could not be

seen at naked eyes. And at 0.1% of the cost of an XFEL.

The Future of Crystallography – or Not Phillips, George N., Jr.1 1Departments of BioSciences and Chemistry, Rice University, Houston TX USA 77005

Crystallography has contributed in remarkable ways for more than a hundred years, contributing structural information to physics, chemistry, materials science, biology, medicine and more. Macromolecular crystallography, beginning with the solution of the myoglobin structure has thrived for more than fifty years, contributing to work deserving of many Nobel prizes and yielding the public archival of more than 100,000 depositions of atomic coordinates.

The development of other complementary techniques for obtaining more or less complete atomic or near-atomic resolution structural information about macromolecules includes NMR, cryo-electron microscopy, microED, XAFS, new methods in small and wide angle solution scattering. Crystals are not required for these methods. A crystal in a diffraction experiment is a two-edged sword. It offer incredible signal averaging over a multitude of unit cells, providing an incredibly precise read-out of the average structure of the basic repeating unit but yet constrains the motions we seek to observe in a complete description of the system. What if we need to move beyond average structures in our narratives about structure-function relationships in macromolecular machinery? What kinds of time-resolved experiments are possible? Can we describe energy landscapes for the behaviour of these machines? After more than a century is crystallography finally reaching the limits of its value?

MS#1

Membrane proteins

Crystal structures of the gastric proton pumpAbe, Kazuhiro1,2

1Cellular and Structural Physiology Institute, Nagoya Univ., Nagoya, Japan2Graduate School of Pharmaceutical Sciences, Nagoya Univ., Nagoya, Japan

The gastric proton pump, H+,K+-ATPase is a P-type ATPase that is responsible foracidifying the gastric juice up to pH 1, and is thus an important drug target for treatinggastric acid-related diseases. I will present the crystal structures of the H+,K+-ATPase incomplex with two acid blockers, vonoprazan and SCH28080, in the luminal-open E2Pstate. These drugs have partially overlapped, but clearly distinguishable, binding modes,which are defined in the middle of a conduit running from the gastric lumen to the cation-binding site. The crystal structures also revealed a conserved lysine residue that points tothe juxtaposed carboxyl residues in the cation-binding site. The unusual configuration ofthe cation-binding site enables the extrusion of a single proton into the pH1 solution of thestomach, which corresponds to a million-fold proton gradient across the membrane, thehighest known cation gradient in any mammalian tissue.

Figure.1. Gastric proton pump in the lipid bilayer

Chaperone-like encapsulation of insecticidal toxinsBusby, Jason1; Marshall, Sean2; Hurst, Mark2; Lott, Shaun1

1The University of Auckland, New Zealand2AgResearch, New Zealand

ABC toxin complexes are insecticidal protein complexes made up of a pentameric "A"component that binds to a target cell, and a heterodimeric "BC" subcomplex. The B proteinand N-terminal domain of C (CNTD) forms a remarkable hollow shell that encapsulates andsequesters the cytotoxic C-terminal domain of C (CCTD) inside. We have investigated theNew Zealand insect pathogenic bacterium Yersinia entomophaga. This bacterium has atoxin complex locus that contains two C genes with different CCTD toxins, allowing multipledifferent toxin domains to be delivered by a common mechanism.

We have determined the structure and function of a third, previously uncharacterised Cprotein produced from a distant genomic locus. Using X-ray crystallography and small-angle X-ray scattering, we show that the toxic cargo protein is encapsulated in an unfoldedor disordered state, with the interior surface of the shell functioning similar to chaperoneproteins to stabilise the cargo. We have also determined the X-ray structure of the toxindomain, revealing it to be an ADP-ribosyltransferase toxin. Testing this protein againstcultured insect cells, we show that it attacks the cytoskeleton and causes actin clustering.Together these results show how the ABC toxin delivery system allows for a diverse set ofproteins to be delivered into target cells by a shared mechanism.

Figure.1. Structures of the YenB/YenC3NTD (left)and the cytotoxic YenC3CTD (right) from Y. entomophaga.

Snapshots of GPCR-G protein complexesGlukhova Alisa1

1Drug Discovery Biology theme, Monash Institute of Pharmaceutical Sciences, MonashUniversity, Parkville 3052, Victoria, Australia

G protein-coupled receptors (GPCRs) are integral membrane proteins that integrateexternal stimuli through generation of various signals inside the cell. They are importantdrug targets and account for over a third of current pharmaceuticals. Until recently, allstructural information on these membrane proteins came from the x-ray crystallography,however, recent advances in single molecule cryo-electron microscopy (cryo-EM) has madepossible structural investigations into more complex systems. In particular, our laboratoryhas solved multiple GPCR complexes bound to their downstream signalling partners, Gproteins. Volta-phase plate cryo-EM and recent advances in data processing allowed us toobtain “side-chain resolution” structures of agonist-bound calcitonin receptor (CTR),glucagon-like peptide-1 receptor (GLP-1R), in complex with Gs heterotrimer, and A1

adenosine receptors in complex with Gi heterotrimers (Figure 1). The combination ofstructural data with mutagenesis and pharmacology is enriching our understanding ofmechanisms of GPCR-G protein selectivity, ligand binding at activated GPCRs andmechanisms of biased signalling.

Figure.1. Structure of an A1AR-Gi complex solved by cryo-EM.

Structural snapshots of manganese uptake in Streptococcuspneumoniae.

Maher, Megan J.1; Sjöhamn, Jennie1; Mcdevitt, Christopher A.2.

1Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, LaTrobe University, Melbourne VIC 3086, Australia.2Department of Microbiology and Immunology, The Peter Doherty Institute for Infection andImmunity, University of Melbourne, Melbourne VIC 3000, Australia.

Bacterial infection involves a constant tug-of-war between host and pathogen for theessential nutrients of life. The acquisition of the first-row transition metal ions (for example,iron, zinc, and manganese) from the host is crucial for the survival and propagation ofpathogenic bacteria. The primary transporters used by bacteria to scavenge these essentialtrace metals are the ATP-binding cassette (ABC) permeases. Accordingly, any loss ordisruption to the function of these transporters severely impairs bacterial virulence. Despitethis, how ABC permeases recognise and acquire their cognate metal ion cargo remainspoorly understood. Given the essential role of ABC permeases in bacterial virulence andtheir absence from eukaryotic genomes, knowledge of the molecular details of thesetransporters will provide novel opportunities for antimicrobial exploitation.

Streptococcus pneumoniae is a Gram-positive human bacterial pathogen that isresponsible for more than 1 million deaths every year. The S. pneumoniae ABCpermease, PsaBCA, is a manganese-specific uptake transporter that is essential for growthand in vivo virulence. This presentation will describe our work in understanding howtransition metals are bound by the metal-recruiting protein PsaA and delivered to thePsaBC transporter, in addition to our recent determination of the high resolution crystalstructure of the entire PsaBC transporter. 

Structure-based drug discovery in Alzheimer’s diseaseParker, Michael1,2; Hermans, Stefan1,2; Crespi, Gabriella1,2; Gooi, Jon1,2; Doughty,Larissa1,2; Nero, Tracy1,2; Markulić, Jasmina1,2; Ebneth, Andreas3; Wroblowski, Berthold3;Oehlrich, Daniel3; Trabanco, Andrés4; Rives, Marie-Laure5; Hancock, Nancy1,2, Miles,Luke1,2

1ACRF Rational Drug Discovery Centre, St. Vincent’s Institute of Medical Research, Fitzroy,Victoria 3056, Australia.

2Department of Biochemistry and Molecular Biology, Bio21 Molecular Science andBiotechnology Institute, University of Melbourne, Parkville, Victoria 3010, Australia.

3Janssen Research & Development, a Division of Janssen Pharmaceutica N.V, 2340Beerse, Belgium

4Neuroscience Medicinal Chemistry, Janssen Research & Development, 45007 Toledo,Spain

5Molecular and Cellular Pharmacology, Janssen Research & Development, LLC, La Jolla,CA 92121, USA

Dementia, including Alzheimer’s disease (AD), affects more than 50 million peopleworldwide with economic costs running into the hundreds of billions of dollars each year.Hence, disease-modifying treatments are urgently sought. The mechanisms by which thedisease progresses to cognitive decline in the sufferer are complex and not fully elucidated.A defining pathological feature is the deposition of extracellular plaques composed primarilyof misfolded amyloid beta (Aβ) peptide: a proteolytic breakdown product of the much largerAmyloid Precursor Protein. There is accumulating evidence that oligomeric soluble forms ofAβ can compromise neuronal functions and trigger cell death.

Expression and activation of the microglial cell surface receptor CD33 has been linked tolate-onset AD, thus inhibition might be an effective therapy against disease progression.The lack of progress toward the discovery of selective CD33 inhibitors has been hamperedby the absence of an atomic resolution structure. We have determined the crystalstructures of CD33 alone and bound to a high-affinity, subtype-selective small moleculecalled P22 and use these structures to identify key binding residues by site-directedmutagenesis and binding assays to reveal the molecular basis for its selectivity towardssialylated glycoproteins and glycolipids. We show that P22 increases uptake of the toxic ADpeptide, Aβ, into microglial cells. Thus, the P22 binding site on CD33 is a promising targetfor developing therapeutics to promote clearance of the toxic Aβ peptide that is thought tocause the disease.

An insight in the assembly mechanism of the beta common cytokine receptors Cheung Tung Shing Karen S.1,2, Broughton Sophie E.1,2, Nero Tracy L.1,2, Dhagat Urmi1,2, Griffin Michael DW.2, Hercus Timothy R.3, Lopez Angel F.3, Parker Michael W.1,2. 1 Australian Cancer Research Foundation Rational Drug Discovery Centre, St. Vincent’s Institute of Medical Research, Fitzroy, Victoria 2 Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria, Australia 3 The Centre for Cancer Biology, SA Pathology and UniSA, Adelaide, South Australia

The beta-common (c) cytokines, namely granulocyte-macrophage colony stimulating factor (GM-CSF), interleukin (IL)-3 and IL-5, regulate normal and malignant haematopoiesis, with emerging non-haematopoietic roles. They activate several signalling pathways, which promote cell proliferation and differentiation, by binding to a signalling unit consisting of a cytokine specific -subunit and a shared -subunit 1. The prevailing paradigm is that the cytokine and -subunit first form a binary complex, which then associates with a c homodimer to form a hexameric ternary complex. Certain signalling pathways may require the self-assembly of two hexamers to form a dodecameric complex 2,3.

Our studies suggest surprising alternative scenarios in the c cytokine receptors assembly pathway, which may be relevant to other Type I receptors. Analytical ultracentrifugation suggests that the cytokine can independently associate with the c dimer, challenging the prevailing hypothesis about the formation of an initial cytokine:-subunit binary complex before associating with the c dimer. We have also observed the formation of the dodecameric signalling complex in solution for the first time using small angle X-ray scattering, analytical ultracentrifugation and transmission electron microscopy. In addition, we have identified an antibody that interferes with higher order complexes formation, a powerful tool to discriminate between the biological functions of the hexamer versus the dodecamer. We have determined the crystal structure of this antibody complexed to the c receptor. This antibody could also form the basis for the development of more potent antibodies that might be useful as therapeutics in diseases such as asthma, where the c cytokines are involved.

Alternative assembly mechanism of the c cytokine receptor signaling complex The current paradigm is that the cytokine and the -subunit first form a low affinity binary complex before associating with the c dimer to form a high affinity ternary complex, which adopts a hexameric and dodecameric arrangement to signal (left to middle). Our studies indicate the possibility of an alternative mechanism where the cytokine first associates with the c dimer before binding of the -subunit to form the hexameric and dodecameric signaling complexes (right to middle).

1 Hercus, T. R. et al. Role of the beta Common (betac) Family of Cytokines in Health and Disease. Cold

Spring Harb Perspect Biol 10, 6, doi:10.1101/cshperspect.a028514 (2018). 2 Hansen, G. et al. The structure of the GM-CSF receptor complex reveals a distinct mode of cytokine

receptor activation. Cell 134, 496-507, doi:10.1016/j.cell.2008.05.053 (2008). 3 Broughton, S. E. et al. Conformational Changes in the GM-CSF Receptor Suggest a Molecular

Mechanism for Affinity Conversion and Receptor Signaling. Structure 24, 1271-1281, doi:10.1016/j.str.2016.05.017 (2016).

MS#2

Crystal engineering

Crystal Engineering of Porous Frameworks for Gas sorption and Catalysis Kumar Biradha Department of Chemistry, Indian Institute of Technology, Kharagpur-721302, West Bengal, India.

Crystal engineering deals with designing functional materials with pre-defined architectures of molecules and functional properties. A thorough understanding of the intermolecular interactions, which control the crystal packing and formation of supramolecular aggregates, is necessary in this context. Among the various intermolecular interactions hydrogen bonding and coordination bonding are the most important tools for the design of supramolecular assemblies given their strength and directionality. Identification of robust interaction patterns, supramolecular synthons, for a given functional group, and utilization of such patterns for building higher dimensional structures in a predictive manner is hugely successful and well employed strategy in crystal engineering. In my presentation some of our recent results on design and synthesis of organic and metal-organic frameworks and their applications in gas sorptions and in catalysis for CO2 fixation, oxygen evolution and hydrogen evolution reactions will be discussed.

Figure.1. a) cubane like water cluster incorporated into (b) 2D-organic framework which facilitatates HER. (c) cubooctahedron clusters as SBU leads to (d) MOF that facilitates CO2 fixation reactions

a) b)

c) d)

O2W

(a) (b) (c)

Selective carbon dioxide capture through adopting thebackbone embedded amines into porous coordination

polymers, ‘the third approach’.Chahine Ali 1; Batten Stuart 1; Turner David 1;

1School of Chemistry, Monash University, 19 Rainforest Walk, Victoria 3800, Australia.

E-mail: Ali.Chahine@monash.edu

There are three different synthetic approaches by which amines can be incorporated into

porous coordination polymers: (i) post-synthetically, (ii) covalently attached-pendant amines

and (iii) the backbone embedded amines of the bridging ligands [1]. Conceding the third

approach, several porous coordination polymers have been synthesized using

carboxyl/amine hybrid ligands amalgamated with transition metals salts. Their selective

Carbon dioxide versus nitrogen gas capture was examined. One of the captivating results

so far was displayed by the net poly-[Zn2(H4L1)]∙(H2O)8, (a), that captured 23.5 cm3/g of

CO2 at 0 ⁰C, 1 atm versus 6.1 cm3/g of N2 at 77K, 1 atm. Where H8L1 is N,N’-tetrakis(3,5-

dicarboxyphenylmethyelene)-1,4- transdiaminocyclohexane. In addition, highly porous nets

have been synthesized based on linear diamine ligands with voids up to 65 % for poly-

[Cu2(H4L2)(H2O)2] , (b),and 62 % for poly-[Cu8((H)(L3)2)(Cl)(H2O)4]∙((CH3)2NH)∙(H2O)4 ,(c).

Where H8L2 and H8L3 are N,N’-tetrakis(3,5-dicarboxyphenylmethyelene) ethylenediamine

and N,N’-tetrakis(3,5-dicarboxyphenylmethyelene)-1,3-diaminopropane respectively .The

CO2 capture of these new materials is ongoing.

[1] A.J. Emerson, A. Chahine, S.R. Batten, D.R. Turner, Coordination Chemistry Reviews,365 (2018) 1-22.

Exploration of Structural Transformations and CatalyticSelectivity in Tailored Flexible Metal-Organic FrameworksHoi Ri Moon1

1Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST),Ulsan 44919, Republic of Korea

Flexible MOFs have attracted great attention, since they show the structural transitionphenomena such as gate opening and breathing, upon the input of external stimuli. Thesephenomena have significant implications in their adsorptive applications. Recently, ourgroup reported the direct capture of these phenomena, triggered by CO2 molecules, in awell-designed flexible MOF with a macrocyclic complex possessing rotational sites andmolecular gates (designated as flexMOF). In this talk, we expand this MOF system bydiversifying functional groups (-OH, -CH2, -CN) on pendant arms of macrocyclic complexesthat can act as a molecular gate, so that in-depth structural studies and its utilization asheterogeneous catalysts are feasible. Particularly with flexMOF(CN), active transition metalions are anchored to the MOF scaffold through coordination of metal ions with the freenitrile groups in the pores (Figure 1), without losing the flexible nature upon CO2 pressure.We expected the synergistic effect of the flexible behaviors on single-site catalysis andtested it in gas-phase ethylene oligomerization. Interestingly, in CO2 atmosphere at thegate-opening pressure, the catalytic conversion efficiency was significantly improved, andthe selectivity also changed. Therefore, our results show that flexible MOFs can give anopportunity to control and enhance the catalytic performances.

Figure.1 Schematic illustration of anchoring catalytic active sites in a tailored flexible MOF.

Understanding polymorphism using hydrogen bond propensitiesStevens, Joanna S.1; Maloney, Andrew G. P.1; Pidcock, Elna1; Sykes, Richard A. 1; Wood,Peter A.1

1The Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge, UK, CB2 1EZ

Traversing the solid form landscape can lead to substantial risk or untold opportunity. Lackof control around crystal form polymorphism can have a critical impact on formulatedproduct robustness, with pharmaceuticals having been withdrawn from the market uponunexpected appearance of a more stable polymorph. However, a detailed understanding ofthose same solid form landscapes can provide an opportunity to generate materials withdesired properties through crystal engineering.

The Cambridge Structural Database contains over 960,000 crystal structures, with datapoints from many millions of individual intermolecular interactions. We can use this datafrom every crystal structure ever published to understand the solid form landscape of anovel material. What are the risks of polymorphism, and can we engineer specific packingmotifs?

The Hydrogen Bond Propensity method makes use of statistics derived from hydrogenbonds observed in similar crystal structures, along with an understanding of the chemistryof a molecule, to make predictions on the likelihood of forming specific interactions in thesolid state. When combined with an understanding of the coordination environment of thefunctional groups of that molecule, we can generate a landscape of likely hydrogenbonding networks. Understanding where a solid form lies on this landscape is critical tounderstanding the risk of polymorphism.

We will describe the Hydrogen Bond Propensity method and its application tounderstanding polymorphism in the organic solid state, highlighting improvements that weare making to the method and discussing how it can be applied to the design of novelmaterials.

The energies of non-standard intermolecular interactions arecompetitive with conventional hydrogen bondingTiekink, Edward R.T.1

1Research Centre for Crystalline Materials, School of Science and Technology, SunwayUniversity, Bandar Sunway, 47500 Selangor Darul Ehsan, Malaysia

Hydrogen bonding is a favoured supramolecular synthon in the crystal engineeringcommunity, working in both the organic solid-state and for coordination chemists. Beingsmall and electron-deficient, hydrogen can reliably approach suitable, electron-rich donorsto form directional interactions. Analogous interactions involving hydrogen bound to carbonconsistently form interactions such as C‒H…O and C‒H…(arene) although, usually, theseinteractions impart less energy of stabilisation than conventional hydrogen bonding of thetype O‒H…O. It turns out that chelate rings, formed by, typically an anion coordinating in abidentate mode to a metal centre can also participate in C‒H…(arene) interactions. Thus,in a crystal a C‒H residue of a chelate ring can interact with a proximate arene ring. Moreinteresting are circumstances where a C‒H residue can interact with the -system definedby the chelate ring itself, that is, participate in a C‒H…(chelate) interaction. In the sameway as … stacking interactions are well established, analogous interactions of the type(chelate ring)…(arene) and (chelate ring)…(chelating) stacking can occur in crystals ofsterically unencumbered metalorganic species. These types of interactions along withsecondary bonding interactions (for example, tetral, pnicogen and chalcogen) andmetal…metal interactions, for example, aurophilic (Au…Au) interactions, all provide energiesof stabilisation in their crystals calculated to be at least of the same order of magnitude asdoes conventional hydrogen bonding. The implications of these results, revealed by high-level computational chemistry by many, independent research groups are discussed interms of the perennial question in (small) molecular crystallography: how are crystalsformed?

Crystal Engineering of scented inclusion crystal and itssustained-release propertyUekusa, Hidehiro; Sano, Fumiaki; Sekine, Akiko

Department of Chemistry, Tokyo Institute of Technology,

Ookayama 2, Meguro-ku, Tokyo 1528551, Japan. E-mail: uekusa@chem.titech.ac.jp

The design of crystal that accommodates and release of liquid fragrant compound isimportant technique because it can also be utilized to solidify liquid pharmaceuticalcompound or other functional molecules. In this work, limonene and other monoterpenefragrant liquid compounds are target guest molecule of the inclusion crystallization, whichalso are released from the crystal gradually.

As a host framework, a Bisphenol A derivative with trifluoromethyl groups (BPAF) wasselected to accommodate the guest molecule, which can form a linear structure with twohydrogen boding OH groups at terminals, and has two benzene groups to catch the guestmolecule with weak interactions. Moreover, in order to expand the framework to fit theguest molecule, an additional spacer molecule was incorporated into the BPAF chain withOH...N hydrogen bonds.

This crystal engineered host framework successfully accommodated the limonene guestmolecule within a channel structure with aromatic rings as the wall to form an inclusioncrystal (Fig. 1). The similar inclusion crystals were also obtained to other monoterpenes.In ambient condition or mild heating, the fragrant guest molecules escaped gradually fromthe crystal and the speed depends on the channel volume and guest molecular size.Furthermore, on the release of guest molecules, the host framework showed two-stepssingle-crystal-to-single-crystal structure change to close the empty inclusion channel withflip of BPAF molecules. This kind of design of host framework with BPAF and spacermolecule can be utilized to include other small molecules to realize a sustained-releasefeature of crystalline materials.Figure.1. Structure of D-Limonene inclusion crystal

MS#3

Novel synchrotron and neutron applications

Shining a light on Martian processes using in situ neutron andsynchrotron techniquesBrand, Helen E. A.1,

1Australian Synchrotron, ANSTO, 800 Blackburn Rd., Clayton, VIC 3168, Australia

When constructing geophysical models of planetary bodies, the phase relations andphysical properties of constituent materials at relevant temperature and pressure conditionsare invaluable inputs. This contribution will explore in situ applications to Martian problemsand explore how we can learn more about surface and crustal processes on the red planet.

Jarosite formation and stability.

Jarosites minerals are of great importance to a range of mineral processing and researchapplications. There has been a recent resurgence in interest in jarosite since its detectionon Mars. In this context, the presence of jarosite has been recognised as an indicator ofwater at the surface of Mars in the past & it is hoped that their study will provide insight intothe environmental history of Mars. To this end we are engaged in a program to studyjarosites, their formation and stability behaviour.

Salt hydrate diapirs in the Martian crust.

Density inversions within sedimentary sequences can have a significant effect on theevolution of geological structures within a planetary crust. The overwhelming evidence forliquid water at some point in Martian history makes it likely that evaporates and ice will bepresent in the sedimentary record, and these will be buoyant with respect to overlying caprocks. In this study we have investigated the physical properties of salt hydrates todetermine how a buoyant layer overlain by a denser layer behaves over time andconsidered the implications for the surface geology of Mars.

Quantitative Coherent Diffraction Imaging of Shale Cuttings Chattopadhyay, Basab1; Cerasi, Pierre2; Mürer Fredrik K.1; Chushkin, Yuriy3; Zontone, Federico3; Gibaud Alain4 and Breiby, Dag W.1 1Department of Physics, Norwegian University of Science and Technology (NTNU), Høgskoleringen 5, 7491 Trondheim, Norway. Email: basab.chattopadhyay@ntnu.no 2SINTEF Industry, Formation Physics Dept, PB 4760 Sluppen, 7465 Trondheim, Norway. 3ESRF, The European Synchrotron, 71 avenue des Martyrs, 38043 Grenoble Cedex 09, France. 4LUNAM, IMMM, UMR 6283 CNRS, Faculté des Sciences, 72085 Le Mans Cedex 09, France.

Over the past decade, Coherent Diffraction Imaging (CDI) has emerged as a suitable alternative to traditional microscopic methods, enabling lensless imaging with high spatial resolution ~5nm. 1,2 CDI relies on the use of an isolated sample which when fully illuminated by a coherent plane X-ray beam produces a speckled diffraction pattern at far-field regime. Provided that the diffraction pattern is sampled finer than the Nyquist frequency, the real space image can be reconstructed using an iterative algorithm. So far, CDI has been successfully utilized to image a variety of objects such as gold nanocrystals, biological cells, bone fragments etc.1,3 In this presentation, we describe quantitative CDI study of shale cuttings of size 2-4 µm. To the best of our knowledge, this is the first use of CDI to image such specimens. The sample, Pierre Shale 1 mined from Colorado (US) 4 is mainly composed of chlorite, illite, smectite and quartz, and exhibits a complex pore structure yet to be fully understood. CDI represents the most suitable technique to explore the 3D microstructure. CDI measurement was performed at the ID10 beam line of the ESRF, France5 and wide-angle X-ray diffraction (WAXD) data was collected in tandem. This combined use of CDI and WAXD enabled 3D reconstruction of the electron density distribution across the entire fragments and quantification of their crystalline phases. Given in Fig. 1 are the diffraction pattern and the reconstructed image of a shale fragment. The results allowed appreciation of the microstructure of shale particles and establish structure-property correlations.

Figure.1. (a) Diffraction pattern collected in the far-field regime and (b) 3D section of the reconstructed image. Regions of high electron density are colored red while low electron density regions are colored grey. The scale bar is 1µm (1) Miao, J.; Ishikawa, T.; Robinson, I. K.; Murnane, M. M. Beyond Crystallography: Diffractive Imaging Using Coherent x-Ray Light Sources. Science. 2015, 348 (6234), 530–535. (2) Chapman, H. N.; Nugent, K. A. Coherent Lensless X-Ray Imaging. Nat.

Photonics 2010, 4 (12), 833–839. (3) Skjønsfjell, E. T. B.; Kleiven, D.; Patil, N.; Chushkin, Y.; Zontone, F.; Gibaud, A.; Breiby, D. W. High-

Resolution Coherent x-Ray Diffraction Imaging of Metal-Coated Polymer Microspheres. J. Opt. Soc. Am. A 2018, 35 (1), A7.

(4) Cerasi, P.; Lund, E.; Kleiven, M. L.; Stroisz, A.; Pradhan, S.; Kjøller, C.; Frykman, P.; Fjær, E. Shale Creep as Leakage Healing Mechanism in CO 2 Sequestration. Energy Procedia 2017, 114, 3096–3112.

(5) Chushkin, Y.; Zontone, F.; Lima, E.; De Caro, L.; Guardia, P.; Manna, L.; Giannini, C. Synchrotron Radiation Three-Dimensional Coherent Diffractive Imaging on Non-Periodic Specimens at the ESRF Beamline ID10. J. Synchrotron Rad 2014, 21, 594–599.

XRD data from small aggregating crystals: Trials andtribulations

Darmanin, C.,1 Holmes, S.,1 Ve, T.,2 Meents, A.,3 Kobe, B.,4 Hunter, M.,5 Du Pointe, D.,5

Spence, J.,6Liu, W.,6 Flueckiger, L.,1 Chapman, H.,3 Nugent, K.,1 Abbey, B.1

1ARC Centre of Advanced Molecular Imaging, Department of Chemistry and Physics, LaTrobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086,Australia2Institute for Glycomics, Griffith University Gold Coast Campus, Southport, QLD,4222, Australia,3Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg,Germany4School of Chemistry and Molecular Biosciences and Institute for MolecularBioscience (Division of Chemistry and Structural Biology) and Australian InfectiousDiseases Research Centre, University of Queensland, Brisbane, 4072, Australia.5LCLS, SLAC National Accelerator Laboratory, Menlo Park, CA, USA.6Arizona State University, Department of Physics, Tempe AZ 85287, USA

Generating X-ray data from very small protein crystals is becoming more achievable due tothe recent advancements of macro crystallography beamlines at synchrotrons and X-rayFree Electron Laser (XFEL) facilities. In recent years, we have seen the development ofsmaller and highly focused crystallography beamlines around the world and with thisdevelopment it has allowed us to push the size limits for data collection on small crystals.Using a silicon chip delivery method developed at DESY we show, using the P11 beamlineat PETRA III setup which is capable of a beam size focus of 2 microns and the introductionof a capillary beam stop, how we improved the data quality from needle like protein crystalsat a synchrotron source. Using a serial crystallography type data collection method weshow the simplicity of data collection on our small crystals and how reducing thebackground in your sample can make a significant effect on data quality. We also showhow an XFEL can help further improve data from these small crystals for structuredetermination.

Refining local structural disorder using combined synchrotron X-ray and spallation neutron total scattering/pair distributionfunctionsKeen, David1

1ISIS Facility, Rutherford Appleton Laboratory, Harwell Campus, Didcot, Oxfordshire OX110QX, United Kingdom.

Local deviations from the average crystalline structure are receiving increased interest inmany areas of crystallography,1 whether it is investigations of structure across phaseboundaries in ferroelectrics,2 the arrangements of molecules in photovoltaics,3 defects inminerals such as hydrogrossular,4 or even the mechanisms for 'solid-state' amorphization inMOFs.5 High-quality total scattering data provide an excellent experimental foundation foranalysis of such systems, data which are now routinely available at X-ray synchrotron andspallation neutron facilities. This talk will describe the means of collecting these data, showhow the data might be refined using RMCProfile,6 and present recent results from some ofthe examples listed above.

[1] D A Keen and A L Goodwin, 'The crystallography of correlated disorder', Nature 521 303 (2015)

[2] M S Senn et al, 'Emergence of long-range order in BaTiO3 from local symmetry-breaking distortions', Phys

Rev Lett, 116 207602 (2016); N Zhang et al, 'The Missing Boundary in the Phase Diagram of PbZr1-xTixO3',

Nature Comm, 5 5231 (2014); P M M Thygesen et al, 'Local structure study of the orbital order/disorder

transition in LaMnO3', Phys Rev B, 95 174107 (2017)

[3] P S Whitfield et al, 'Structures, phase transitions and tricritical behavior of the hybrid perovskite methyl

ammonium lead iodide', Sci Rep, 6 35685 (2016)

[4] D A Keen, D S Keeble and T D Bennett, 'Neutron and X-ray total scattering study of hydrogen disorder in

fully hydrated hydrogrossular, Ca3Al2(O4H4)3', Phys Chem Miner, 45 333 (2018)

[5] R Gaillac et al, 'Liquid metal-organic frameworks', Nature Mater 16 1149 (2017) (and references therein)

[6] M G Tucker et al, 'RMCProfile: Reverse Monte Carlo for polycrystalline materials', J Phys: Cond Mater, 19

335218 (2007)

Nanoplastics – protein interaction: A scattering study of transition from soft and hard corona Shinji Kihara1, 2 Jitendra P. Mata3, Chris K. Seal1, 2, Ingo, Köper4, Duncan J. McGillivray*1, 2 1 School of Chemical Sciences, The University of Auckland, Auckland 1010, New Zealand 2 The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand 3 Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organization, Lucas Heights, NSW 2234, Australia 4 Institute for Nanoscale Science and Technology, Flinders University, Adelaide 5042, Australia

There is growing concern about plastic waste in the environment, and its impact on biological organisms. While bulk plastics are thought to be non-toxic, when the plastics break down to a sub-micron length scale (i.e. nanoplastics), they obtain extra mobility inside living things, and may cause various adverse effects1,2. This, coupled with a lack of knowledge surrounding the dangers from different types of plastics, prevents well-designed responses to the problem. Hypothetically, the potential adverse effects are caused by protein denaturation, oxidative stress and/or cellular membrane damage. However, the inherent complexity of biological systems makes it challenging to gain a mechanistic understanding. Adding complexity to this problem, the potential adverse effects are highly dependent on the nature of nanoparticles (NPs) – the contributing factors could include elemental composition, chemistry of the plastic surface, and/or size of the plastic particle.3,2,4

When in biological systems, nanoplastics are surrounded by various types of proteins5. The structure of proteins surrounding nanoplastics are important parameters to understand the interaction of nanoplastic/protein composite. We carried out light scattering and small angle scattering (SAS) experiments to explore the structure of the protein corona on monodisperse polystyrene spheres using a model protein human serum albumin (HSA). The transition from a “soft” to a “hard” interaction between the nanoparticle and the protein was observed when pH is lowered from 7.4, and the implications of this on nanoplastic toxicity is discussed.

1. Sharma, S.; Chatterjee, S. Environmental Science and Pollution Research 2017, 24, 21530-21547.

2. Lee, K.-W.; Shim, W. J.; Kwon, O. Y.; Kang, J.-H. Environmental science & technology 2013, 47, 11278-11283.

3. Mattsson, K.; Johnson, E. V.; Malmendal, A.; Linse, S.; Hansson, L.-A.; Cedervall, T. Scientific Reports 2017, 7, 11452.

4. Cui, R.; Kim, S. W.; An, Y.-J. Scientific reports 2017, 7, 12095.

5. Tenzer, S.; Docter, D.; Kuharev, J.; Musyanovych, A.; Fetz, V.; Hecht, R.; Schlenk, F.; Fischer, D.; Kiouptsi, K.; Reinhardt, C. Nature nanotechnology 2013, 8, 772.

Introduction of 2D Supramolecular Crystallography Beamline

(BL2D-SMC) at Pohang Light Source II in Korea

Moon, Dohyun1

1Beamline Department, Pohang Accelerator Laboratory 80 Jigokro-127-beongil, Nam-gu,Pohang Gyeongbuk, 37673, Korea

The 2D supramolecular crystallography beamline (BL2D-SMC) at Pohang Light Source II inKorea has been dedicated for the single crystal crystallography of small molecule andsupramolecule user groups. The beamline is located at the 2D bending magnet port in the3GeV storage ring of Pohang Light Source II. The optics of beamline are consist of twomirrors (one vertical collimation and one focusing) and a Si (111) double crystalmonochromator to in the tunable energy range between 8 and 20 keV (1.5 and 0.6 Å). Thenew developed BL2D-SMDC (SupraMolecular Data Collection) software has an interactiveGUI and is designed to run on a Windows operating system, and easy to access andcollect data for the first time visited users. HKL3000sm is used for cell refinement and datareduction. The large area CCD detector (Rayonix MX225HS) has installed at the beamlinein Mar. 2018. This CCD detector is very fast data collection (10 image per sec with 2x2binned, 16bits standard) and high quality with high dynamic range (1x1 non-bin, 18 bitsHDR) with no inactive area. It will give a chance to get the structural change of the singlecrystals or to get the high resolution image data. Recently, this beamline is performingeither general crystallography experiment such as hollow structure (MOF and cagestructure and very tiny size crystal (< 10 μm3)) or non-ambient crystallography such asvariable temperature, gas sorption and photo-excitation to the crystal. The status,instruments and several application using 2D beamline will be presented.

MS#4

Applications of cryo-EM to structural biology

Structural Basis for Substrate Translocation by the AAA ATPaseVps4Hill, Chris

University of Utah

Biochemistry

Many cellular membrane fission reactions are driven by ESCRT pathways, which culminatein remodeling and disassembly of ESCRT-III polymers by the AAA ATPase Vps4. Recentadvances in understanding of the budding machinery will be summarized, with specialemphasis on HIV budding and findings from our 3.2 Å resolution cryo-EM structure of theactive Vps4 hexamer in complex with its cofactor Vta1, ADP·BeFx, and an ESCRT-IIIsubstrate peptide. Five Vps4 subunits form a helix, with interfaces between the first four ofthese subunits apparently bound to ADP.BeFx (ATP) and the interface between the fourthand fifth subunit bound to ADP, as if it is just commencing dissociation from the helix. Thefinal Vps4 subunit completes a notched-washer configuration as if transitioning betweenthe ends of the helix. The ESCRT-III peptide binds in an extended (beta-strand)conformation against the five helical subunits. Two classes of side chain binding pocketsare formed primarily by Vps4 pore loop 1 residues, with four copies of each pocketpropagating along the highly solvated pore through the Vps4 hexamer. The pocketsaccommodate a wide range of residues, while main chain hydrogen bonds help dictatesubstrate-binding orientation. The structure supports a ‘conveyor belt’ model oftranslocation in which ATP binding allows a Vps4 subunit to join the growing end of thehelix and engage the substrate, while hydrolysis and release promotes helix disassemblyand substrate disengagement at the lagging end. In this manner Vps4 may disassembleESCRT-III to reveal a metastable membrane configuration that resolves by fission and virusbudding. This model likely applies to other ESCRT pathways and may be generallyapplicable to multiple other protein-translocating AAA ATPases.

Cryo-EM structures the pore-forming ABC toxin from Yersinia entomophaga provide insights into the dynamic structural rearrangement associated with membrane recognition Piper, Sarah2; Brillault, Lou1,2; Croll, Tristan3; Box, Joseph1; Chassagnon, Irene1; Rothnagel, Rosalba2; Scherer, Sebastian4; Goldie, Kenneth4; Jones, Sandra5; Busby, Jason7; Lott, Shaun6; Hankamer, Ben2; Stahlberg, Henning4; Hurst, Mark5; Landsberg, Michael1,2 1School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia Queensland, Australia. 2Institute for Molecular Bioscience, The University of Queensland, St Lucia Queensland, Australia. 3Cambridge Institute of Medical Research, University of Cambridge, Cambridge, United Kingdom. 4Centre for Cellular Imaging and NanoAnalytics, Biozentrum, University of Basel, Basel, Switzerland. 5Forage Science Group, AgResearch, Christchurch, New Zealand. 6School of Biological Sciences, University of Auckland, Auckland, New Zealand.

ABC toxins are tripartite protein toxin complexes secreted by pathogenic bacteria that prototypically contain three distinct proteins subunits encoded by tc genes. The A subunit, usually encoded by a large, tca-like gene, is responsible for membrane binding and confers host specificity. The B and C subunits (encoded by tcb-like and tcc-like genes) together form a cocoon like structure that encapsulates a highly potent cytotoxin that is encoded by the 3’ end of the tcc-like gene. The mechanism by which the toxin is delivered to targeted cells has not been conclusively demonstrated, but is thought to share at least some similarity with other toxin-translocating pore-forming proteins such as the B. anthracis toxin, which delivers its cytotoxin via a transmembrane pore following receptor-mediated endocytosis. We have recently determined cryo-EM structures of an ABC toxin secreted by the Gram negative insect pathogen, Yersinia entomophaga (YenTc) which highlight the structural transition from soluble prepore to membrane-inserted pore, and unexpectedly reveal a structurally conserved pore forming apparatus, despite high divergence in its sequence and genetic architecture from other complexes belonging to the ABC toxin family. Two chitinase subunits, encoded by genes within the YenTc locus and we present evidence that suggests these unique subunits play an important role in membrane recognition and by extension, the establishment of host tropism.

The structural basis of reversible fibril involved in phaseseparation and neurodegenerative diseases

Liu Cong1 , Gui Xinrui1, Luo Feng1,Li Yichen2, Li Dan2

1Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of OrganicChemistry, Chinese Academy of Sciences, Shanghai 201210, China;2Bio-X Institutes, Key Laboratory for the Genetics of Developmental and NeuropsychiatricDisorders, Ministry of Education, Shanghai Jiao Tong University, Shanghai, China;

Pathological amyloid fibrils are characteristic of highly thermostable cross-β structure1.However, the stable cross-β architecture cannot explain the reversible amyloid fibrilsformed by RNA-binding proteins such as hnRNPA1 and FUS that is involved in the dynamicassembly of stress granules2,3. Here we identified the reversible amyloid cores (RACs) ofFUS and hnRNPA1 that can form reversible amyloid fibrils under the regulation oftemperature and phosphorylation. We determined the atomic structures of the RACs infibrillar forms by micro-electron diffraction and X-ray diffraction. Combined with biochemicaland cellular experiments, we reveal the structural basis of reversible amyloid formationregulated by phosphorylation, and explains how ALS disease-associated mutationabolishes reversibility of RACs which results in abnormal aggregation observed in the brainof ALS patients. Our study sheds light on understanding not only the dynamic amyloidformation in RNA granules but also how the dysregulation of reversible amyloid leads todiseases.

1. Eisenberg, D. & Jucker, M. The amyloid state of proteins in human diseases. Cell 148, 1188-1203 (2012)\

2. Kato, M. & McKnight, S.L. A Solid-State Conceptualization of Information Transfer from Gene to Message to Protein. Annu.Rev. Biochem. 87 (2018).

3. Protter, D.S. & Parker, R. Principles and Properties of Stress Granules. Trends. Cell Biol. 26, 668-679 (2016).

A nanoscale injection mechanism: imaging the sheath contraction of the antifeeding prophage of S. entomophila Mitra, Alok K.1; DesFosses, Ambroise2; Venugopal, H1,3; Joshi, T.1; Heymann, B.4; Hyun. J-K.5; Bhardwaj, P.1,6; Hurst, Mark R. H.6 1 School of Biological Sciences, The University of Auckland, Auckland 1010, New Zealand 2 IBS, Grenoble, France 3 Monash University, Clayton Campus, Clayton, Australia 4 NIAMS/NIH, Bethesda, MD 20892, USA 5 Korea Basic Science Institute, Chungcheongbuk-do, Republic of Korea 6 AgReserarch Lincoln Research Centre, Christchurch, New Zealand

Several biological systems have developed. secretion systems to transfer effector molecules to kill sensitive hosts for gaining survival advantage. These include, bacteriophage-tail like macromolecular microinjection devices composed of a contractile sheath wound around an inner tube with a cell-membrane puncturing assembly (needle) at its tip. The sheath is positioned on a baseplate -a multi-protein complex surrounding the needle and believed to be involved in relaying contraction signal to the sheath. We have focussed on the anti-feeding prophage (Afp), a plasmid-encoded mobile protein microinjection device produced by the bacteria S. entomophila that delivers a protein toxin to kill larvae of a New Zealand pasture-denuding insect pest. Afp shares common features with e.g. T4 tail and type VI secretion systems (T6SS) and elaborates two distinct configurations - the resting state, and the functional state wherein the sheath is contracted, the inner tube is partially exposed and the toxin is extruded into the host (Fig.1). We have previously determined a 2.9 – 4 A resolution structure (Fig.1 inset) of Afp resting state that allowed for de novo atomic modelling and delineation of the full organization of the assembly. We describe here the 3D structure of the contracted state at 3.9A resolution to visualize the remodelling of sheath protein-protein interactions and the energetics driving the contraction process. We also describe the accompanying large scale movement of the baseplate proteins. Together, our work is the first atomic-level depiction of the action mechanism of the full contractile, protein toxin carrying tail-like particle with an eukaryotic host.

Fig.1. Cryo-EM images of in vitro contracted Afp particles in vitrified buffer (contaminating hexagonal ice are apparent). Inset shows the reconstruction of the extended Afp (110 nm in length) at resolution ranging from 2.9 -3.5A.

Hierarchical structure assembly mechanism of Rice dwarf virus

Yusuke Nakamichi1,2, Naoyuki Miyazaki1,3, Kenta Tsutsumi1, Akifumi Higashiura1,4, HirotakaNarita1, Kazuyoshi Murata3, and Atsushi Nakagawa1

1 Institute for Protein Research, Osaka University, Suita, Osaka 565-0871 Japan2 Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science andTechnology, Higashi-Hiroshima, Hiroshima 739-0046 Japan

3 National Institute for Physiological Sciences, Okazaki, Aichi 444-8787 Japan

4 Department of Virology, Graduate School of Biomedical and Health Sciences, HiroshimaUniversity, Hiroshima, Hiroshima 734-8551 Japan

Accurate viral assembly is essential for infection to the host cells and replication. Viruses inthe family Reoviridae have multi-layered shell capsids. The Reoviridae has a wide hostrange, including human, animals and plants. Rice Dwarf Virus (RDV), the causal agent ofrice dwarf disease, infects rice plants and negatively affects rice production. RDV istransmitted to rice plants by vector insects, leafhoppers. RDV has an icosahedral double-layered shell with the diameter of approximately 70 nm and contains 12-segmented doublestranded RNAs as the genome. The innermost layer capsid shell of RDV exhibitsicosahedral T = 1 symmetry, whereas the second layer shell, which was composed of 260copies of trimeric-proteins, shows icosahedral T = 13 symmetry. We have proposed ahierarchical structure assembly mechanism of the double-shelled full particle of RDV basedon the precise atomic structure determined by X-ray crystallography at 3.5 Å resolution(Nakagawa et al., 2003). In this study, we succeeded to produce the intermediate in thesecond shell assembly by designing a second layer protein mutant inhibiting the interactionbetween themselves. The three-dimensional structure of the intermediate was determinedby cryo-EM single particle analysis with a phase plate. The structure revealed that thesecond layer trimeric-proteins primarily bind to the icosahedral three-fold axis on theinnermost shell and the assembly cannot proceed without the interactions between trimerproteins. The order of shell construction is thus suggested to be strictly controlled for theaccurate assembly of the particle.

Figure.1. Hierarchical structure assembly of Rice dwarf virus

A novel metal-bound active site in a hydrolytic enzyme Vinothkumar K.R. National Centre of Biological Sciences, Bangalore Dimethylformamide (DMF) is an organic solvent commonly used in chemical synthesis and due to its polar nature has some properties similar to water. Among its major use are in the leather, printing and petrochemical industries. Remarkably there are no natural source for DMF but can be generated from di and tri methylamine by photochemical degradation. Thus, the major source of DMF is through human industrial activities. Certain microbes have been identified to grow in DMF as the sole carbon source and they use an enzyme called dimethylformamidase (DMFase) to convert DMF into formamide and assimilate into metabolic pathways. The enzyme comprises of two polypeptides with 85 and 15 kDa and thought to exist as an oligomer. Despite its identification around three decades ago, no structural information is available and lack of any sequence similarity to known enzymes has precluded any mechanistic detail. We determined the structure of DMFase by cryoEM, which revealed that the enzyme to exist in two populations - dimeric and tetrameric form. The equilibrium between the oligomeric state can be shifted by varying the amount of salt. Multiple structures of DMFase obtained by EM at high resolution allowed us denovo model building. Subsequently, the cryoEM model was used to phase and solve the crystal structure of DMFase. I will discuss the structure of DMFase, which reveals a novel fold with an iron-containing active site and the substrate entry pathway.

MS#5

Solid state reactions and dynamics

Elastic, plastic and creep deformation in one single crystal:structural investigations by micro focused X-ray diffraction.Grosjean, Arnaud1; Worthy, Anna2; Spackman, Mark A.1, McMurtrie, John C.2; and Clegg,Jack K.3

1School of Molecular Sciences, The University of Western Australia, Perth, WA 6009Australia2School of Chemistry, Physics and Mechanical Engineering, Queensland University ofTechnology, Brisbane, QLD 4001, Australia3 School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane,St Lucia, QLD 4072, Australia

Molecular crystals are often seen as brittle materials that typically crack or break undermechanical stress. However, some molecular crystals can display remarkable mechanicalproperties such as elastic or plastic flexibility. [Cu(Cl-acac)2], for instance, is part of thisclass of crystalline materials that shows flexibility. Indeed, acicular crystals of thiscompound can be reversibly bent several times without showing any evidence of beingcracked, broken or permanently deformed thus displaying elastic flexibility. When put to ahigher stress these same crystals are then permanently deformed thus displaying plasticdeformation.

These intriguing properties surely stem from the nature and arrangement of intermolecularforces present between molecules in the crystal lattice, whereby weak interactions allowmolecules to move sufficiently within a crystal lattice (resulting in flexibility) while strongerinteractions between molecules maintain the crystallinity. Using a micro-focus X-ray beam(available at the MX2 beamline at the Australian synchrotron), it is possible to map changesin the crystal structure in bent crystals to reveal the structural modifications induced bymechanical stress. This kind of measurement have been performed on crystals bent withsufficient stress to be on the edge between elastic and plastic deformation. Furthermore, itwas possible to evidence the occurrence of creep deformation as the structural stressrelaxes over time. These obtained results allow a better understanding of this class ofmaterials by revealing the mechanisms behind their behavior.

Figure.1. Bent [Cu(Cl-acac)2] crystal as mounted at the Australian Synchrotron MX2 beamline with schematicview of the structural (elastic) deformation on the elongated (left) and compressed (right) areas of the crystal.

Temperature-induced intramolecular proton transfer in a novelpolymorph of 2-(2’-hydroxyphenyl)benzimidzole crystalOhhara, Takashi1; Nakao, Akiko2; Munakata, Koji2; Moyoshi, Taketo2; Hanashima,Takayasu2; Kiyanagi, Ryoji1; Hosoya, Takaaki3; Hara, Yoshiaki4

1J-PARC Center, Japan Atomic Energy Agency2Neutron Science and Technology Center, CROSS

3Department of Quantum Beam Science, Ibaraki University

4Department of Industrial Engineering, National Institute of Technology, Ibaraki College

2-(2’-hydroxyphenyl)benzimidazole (HPBI) has an intramolecular O-H…N hydrogen bondand shows photo-induced excited-state intramolecular proton transfer, from the enol form tothe keto form (Fig. 1). So, HPBI and its derivatives have been studied as a candidate ofnew photo-functional materials such as a fluorescent probe and a laser-device. In solid-state, two polymorphs of HPBI were reported and temperature-induced intramolecularproton transfer was suggested in one of those polymorphs, -form, by temperature-dependent measurements of fluorescence excitation spectra [1]. Recently, we found that anovel polymorph (-form) of HPBI crystal co-exists with the -form in a samerecrystallization batch and a peak in the fluorescence excitation spectrum which showsstrong temperature-dependence comes from the -form crystal.

We carried out single-crystal neutron diffraction measurements of the -form at 90K and298K by using SENJU single-crystal diffractometer at J-PARC MLF to observe thetemperature-induced proton transfer in the intramolecular hydrogen bond from the enol-form (O-H…N) to the keto-form (O…H-N). In the result, negative density of atomicscattering length which comes from the proton of the keto-form was observed at 298K eventhough no keto-form was observed at 90K. We also carried out neutron diffractionmeasurements of the -form at 4K and 298K and no keto-form was observed at bothtemperature conditions. These results suggest that the temperature-induced intramolecularproton transfer occurs in the -form. In the -form, HPBI molecule forms strongerintermolecular N-H…O hydrogen bond than that in the -form. This hydrogen-bondpossibly contributes to lowering the potential barrier between the enol and keto-forms.

[1] Konoshima, H. et al. (2012) Phys. Chem. Chem. Phys., 14, 16448-16457.

Figure.1. Intramolecular proton transfer in HPBI.

In situ diffraction characterisation of hydrogen storage materialsRowles, Matthew R.1; Tortoza, Mariana S.2; Griffond, Arnaud2; Humphries, Terry D.2;Sheppard, Drew A.2; Sofianos, M. Veronica2; Buckley, Craig E.2

1John de Laeter Centre, Curtin University, Perth, WA, Australia2Hydrogen Storage Research Group, Fuels and Energy Technology Institute, CurtinUniversity, Perth, WA, Australia

Metal hydrides have been identified as next-generation storage materials for multipleapplications, including hydrogen and thermal energy storage, as well as solid-stateelectrolytes[1, 2]. These hydrides include simple metal hydrides, such as MgH2, complexmetal hydrides[2]., such as NaAlH4, and complex transitional metal hydrides[3], such asMg2NiH4. Current research at Curtin University centres on the (de)stabilisation of thesematerials in order to tailor the materials properties for specific applications, such asconcentrated solar thermal[4] and vehicular energy storage[5, 6]. This is often achievedthrough elemental substitution, which introduces structural changes in the hydrogenstorage materials. The use of powder diffraction gives the ability to quantify these changesand to track structural evolution and reactions in situ with changes in temperature andpressure. The diffraction analyses undertaken include symmetry-mode refinements[7] tostudy structural changes, parametric[8] and sequential refinements to extract quantitativephase analysis where phases were able to be identified, and simple peak fitting whenphases were not. This presentation will highlight the various diffraction methods used forcharacterising hydrogen storage materials and show how it is an invaluable tool in thecharacterisation of materials under various stimuli.

[1] Paskevicius, M., et al., Chem. Soc. Rev., 2017. 46(5): p. 1565-1634.[2] Møller, K., et al., Energies, 2017. 10(10).[3] Humphries, T.D., D.A. Sheppard, and C.E. Buckley, Coord. Chem. Rev., 2017. 342: p. 19-33.[4] Fellet, M., et al., MRS Bull., 2013. 38(12): p. 1012-1013.[5] Schlapbach, L. and A. Zuttel, Nature, 2001. 414(6861): p. 353-358.[6] Zuttel, A., et al., Philos. Trans. R. Soc. A, 2010. 368(1923): p. 3329-42.[7] Campbell, B.J., et al., J. Appl. Crystallogr., 2006. 39(4): p. 607-614.[8] Stinton, G.W. and J.S. Evans, J. Appl. Crystallogr., 2007. 40(1): p. 87-95.

Reversible phase transition between single crystals ofluminescent gold complexSeki, Tomohiro1

1Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido 060-8628, Japan

Single-crystal-to-single-crystal (SCSC) phase transformations are rare albeit attractivebecause precise structure analyses and high quality ordering of the assemblies can beachieved. SCSC phase transitions have been typically induced through temperaturechange and solvent vapor. In 2013, we reported a pioneering example of mechano-inducedSCSC phase transitions of gold isocyanide complexes with photoluminescence colorchanges.[1] In these cases, the reverse phase transitions from the phases obtained aftermechanical stimulation have not been achieved. In this study, we found that a newlyprepared gold isocyanide complex also shows mechanically inducible SCSC phasetransition as well with emission color changes from green to orange (3G/MeOH → 3Oscsc).[2]

Remarkably, the original single crystal phase can be recovered upon exposure of MeOHvapor (3Oscsc → 3G/MeOH), confirming the reversible SCSC phase transitions. Thiscomplex provides the first example of the reversible SCSC phase transition with emissioncolor changes through mechanical stimulation and vapor diffusion. In this paper, the phasetransition mechanism of this system will be discussed in detail.

[1] H. Ito, M. Muromoto, S. Kurenuma, S. Ishizaka, N. Kitamura, H. Sato, T. Seki, Nat.Commun. 2013, 4, 2009; T. Seki, K. Sakurada, H. Ito, Angew. Chem. Int. Ed. 2013, 52,12828–12832. [2] M. Jin, T. Sumitani, H. Sato, T. Seki, H Ito, J. Am. Chem. Soc. 2018, 140,2875–2879.

Figure.1. Photographs of reversible SCSC phase transition (recording under UV light).

Structures and Properties of Porous Molecular CrystalsComposed of Unique H-shape MoleculeYakiyama, Yumi1; Nabuchi Yuta1; Nishimura Mio1; Sakurai Hidehiro1

1Division of Applied Chemistry, Graduate School of Engineering, Osaka University

Porous materials represented by MOF, COF and HOF are widely and intensively studied interms of their high potential for the practical use. They are formed via strong chemicalbonds such as coordination bond, covalent bond and hydrogen bond to possess highstability against the adsorption/desorption process of the guest molecules. Meanwhile,porous molecular crystals which are constructed only with van der Waals type interactionsare rarely reported and often lose porosity and/or undergo structure collapse after theremoval of guest molecules because of the relatively weak intermolecular interactions. Toachieve the new type of porous materials, in this project we focused H-shaped indanedionedimer and found that two pyridyl rings introduced-indanedione dimer 1 showed thereversible crystal structure transformation between porous and non-porous ones throughguest adsorption/desorption with keeping their crystallinity.Crystallization of 1 from CH2Cl2/EtOH afforded non-porous crystal 1close which did notcontain any solvent molecules (Figure 1). After the soaking of 1close in non-polar solventsuch as pentane and hexane, the crystal structure changed to porous one with trapping thesolvent molecules (1open). This porous structure was also obtained selectively by theaddition of one-drop of specific solvent during the crystallization. Further removal of theguest molecule by heating of 1open again afforded the non-porous 1close.

Figure.1. Reversible crystal structure transformation of 1.

Self-Epitaxial Crystallization of All-Conjugated Diblock Copolymer and Phase Separation of Blends Controlled by Orientation Transition

Hua Yang1,2, Rui Zhang3, Yanchun Han3* 1 China Spallation Neutron Source

2 ANSTO 3Changchun Institute of Applied Chemistry, CAS

*e-mail: huay@ansto.gov.au

Abstract

The orientation transition of all-conjugated diblock copolymers poly(p-phenylene)-block-(3-hexylthiophene)

(PPP-b-P3HT) and the blends of P3HT and poly[[N,N-bis(2-octyldodecyl)-napthalene-1,4,5,8-

bis(dicarboximide)-2, 6-diyl]-alt-5, 5‘-(2, 2‘-bithiophene)] (N2200) were systematically investigated by in-

situ temperature-resolved two-dimensional grazing incidence X-ray diffraction (2D GIXD) in step-by-step

heating and cooling process. Moreover, the self-epitaxial crystallization of PPP-b-P3HT and the phase

separation of P3HT/N2200 blends were investigated by this processing. The results of diblock copolymers

showed that the PPP block crystal adopted a face-on orientation while the crystallization of P3HT block was

hindered in as-casted films. Then, the as-casted film was heated in the melting temperature region of PPP

blocks and isothermally crystallized. The partial melting of PPP blocks promoted the P3HT blocks crystallize

in a face-on due to the steric limitation effect, PPP blocks crystallized with a face-on via the self-epitaxy

during cooling. Furthermore, the orientation transition was observed in blends, when pristine amorphous

films are thermally annealed below the melting temperature of P3HT, only the chain segment of P3HT moves,

while P3HT molecule is crystallized, induced by N2200 with face-on orientation.

References

1. Hua Yang, Rui Zhang, Lei Wang, Jidong Zhang, Xinhong Yu, Jiangang Liu, Rubo Xing, Yanhou

Geng, and Yanchun Han*, Macromolecules 2015, 48, 7557−7566.

2. Rui Zhang, Hua Yang, Ke Zhou, Jidong Zhang, Xinhong Yu, Jiangang Liu, and Yanchun Han*,

Macromolecules 2016, 49, 6987−6996.

Please submit the abstracts via email to: gabriel@ansto.gov.au AND oliverp@ansto.gov.au

MS#6

Recent developments in crystal growth

Analysing transmembrane helix interactions using lipid cubicphase crystallisation.Call, Melissa1; Call, Matthew1; Trenker, Raphael1

1The Walter and Eliza Hall Institute, Melbourne Australia

To sense the external environment, human cells rely on around 600 receptors that span themembrane once and collaborate to transmit signals to the cell interior. Many of theinteractions that control their architecture and function are governed by membrane-embedded sequences that allow receptors to interact laterally in the membrane withoutinterfering with external ligand-binding and internal cytoplasmic domains that focusintracellular signalling pathways. While full-length single-pass receptors are yet to bestructurally characterised to high resolution, information can be gleaned by structuralcharacterisation of the isolated transmembrane peptide reconstituted in membranemimetics. Until recently data could only be collected using specialised NMR techniques andit was believed that dynamic movement and a lack of structured ectodomain would preventcrystal growth. We surmised that stable oligomers might be crystallised using lipidic cubicphase with N- and C- termini electrostatic contacts driving crystal growth betweenmonoolein lamellar sheets and native oligomeric interfaces driving crystal growth laterally.We have successfully employed this approach to solve the canonical Glycophorin A dimerand the NK cell receptor signalling module DAP12. Using a set of in silico-designed and invitro-optimised oligomeric peptides we have observed that crystal growth can be influencedby the addition of charged residues in the juxtamembrane sequences. We show thatmembrane embedded interactions of transmembrane helices are stable enough topropagate crystal growth and crystallise in physiologically relevant conformations allowingrapid structural characterisation of this important protein class.

Millennials microcrystals: wouldn’t it be easier to stayhome?Coulibaly, Fasséli1,2; Boudes, Marion1,2; Garriga, Damià1,2; Fryga, Andrew3; Caradoc-Davies, Tom4

1Biomedicine Discovery Institute, Monash University, Australia

2Department of Biochemistry and Molecular Biology, Monash University, Australia

3Faculty of Medicine, Nursing and Health Sciences, FlowCore, Monash University, Australia

4The Australian Synchrotron, Clayton, Australia

Broad access to X-ray microfocus beamlines and the development of free-electronlaser facilities have greatly facilitated the analysis of microcrystals. In addition tounlocking projects where only small crystals were available, these advances haveenabled structure determination of crystals produced in living cells, either in vivo orin cell culture.

Here we investigate whether in cellulo X-ray diffraction experiments may provide amore efficient path to structure determination than classical serial crystallographyapproaches for microcrystals grown in insect cells. We show that flow cytometry canbe used to sort cells containing crystals of the polyhedrin protein and directly usethese cells for in cellulo diffraction experiments at a synchrotron microfocusbeamline. When compared with the analysis of purified microcrystals, in cellulodiffraction produces data of better quality and a gain of 0.35 Å in resolution forcomparable data collection time. Crystals within cells were derivatised with gold andiodine compounds diffusing through the cellular membrane allowing phasing by themultiple isomorphous replacement method. A near-complete model was autobuiltfrom 2.7 Å resolution data.

Thus, in favourable cases, an in cellulo pipeline can replace the complete workflowof structure determination without compromising the quality of the resulting model,while maintaining the protein in a cellular context.

Using mutants designed to alter crystal packing to determinemode of action of inhibitors for multiple herbicide resistance inweedsEno, Rebecca1, Schwarz, Maria1, Freitag-Pohl, Stefanie1, Moore, Jenny2, Mitchell, Glynn2,Steel, Patrick1, Pohl, Ehmke1,3

1Department of Chemistry, and 3Department of Biosciences, Durham University, SouthRoad, Durham, DH1 3LE, United Kingdom

2Syngenta, Jealott’s Hill International Research Station, Bracknell, Berkshire, RG42 6EY,United Kingdom

Multiple herbicide resistance (MHR) in black grass (Alopecurus myosuroides) is a globalproblem which results in a loss of chemical control of black grass weeds in crops. MHR hasbeen linked to the expression of a phi class glutathione-s-transferase (GST), AmGSTF1 1,2

A number of inhibitors were identified using a ligand fishing approach, and variationsproduced on these using synthetic chemistry. Their activity has been confirmed both in vivoagainst black grass and in vitro against AmGSTF1.The focus of this project has been toinvestigate the mode of action of these inhibitors using crystallographic and biophysicaltechniques.

We have successfully crystallised apo AmGSTF1, with crystals diffracting to 1.5 Å.However, the crystal packing form results in loops in the active site region being disorderedas well as preventing small molecule binding in the active site. To enable us to determinethe complete structure we have designed a series of mutants to alter crystal packing. Thestructure of these have been determined, they have a different packing arrangement whichresults in the previously disordered loops being ordered, as well as exposing the active sitefor small molecule binding. These mutants have subsequently been used for seeding andsoaking experiments which have allowed us to determine a complete structure of wild typeAmGSTF1 in complex with inhibitors.

1I. Cummins, D. P. Dixon, S. Freitag-Pohl, M. Skipsey and R. Edwards, Drug Metab Rev, 2011, 43, 266-280.2I. Cummins, D. J. Wortley, F. Sabbadin, Z. He, C. R. Coxon, H. E. Straker, J. D. Sellars, K. Knight, L. Edwards,D. Hughes, S. S. Kaundun, S. J. Hutchings, P. G. Steel and R. Edwards, Proc Natl Acad Sci U S A, 2013, 110,5812-5817.

Membrane-assisted protein crystallizationBudayova-Spano, Monika1

1Université Grenoble Alpes, Institut de Biologie Structurale, UMR5075, 71 Avenue desMartyrs, 38044 Grenoble Cedex 9, France

Two new and emerging uses result in specific challenges for crystallization of proteins. Inboth, precise control of crystal size is essential. New approaches to serial time-resolved X-ray crystallography, where uniformly-sized population of crystals (0.2-10 μm) is used toobtain dynamic structural information [1]. At the other extreme are the requirements of thenext-generation flagship neutron sources, such as the ESS (European Spallation Source,Lund). Because neutrons interact very weakly with matter, much larger (0.1-1.0 mm3)crystals are needed for neutron crystallography [2]. This is, however, the only way tovisualise all of the protons in a protein structure, important information for drug design.

Membrane-assisted crystallization technology, such as dialysis combined with temperaturecontrol, is at the basis of the crystallization devices I will introduce in my presentation. Theyhave been developed recently with the focus to monitor and control the crystallizationprocesses in situ generating the crystals of specific sizes and morphology optimized fordifferent downstream structure determination approaches [3-6]. The membrane acts as aprecision dosing device to control the composition of the crystallization solution, the level ofsupersaturation and its generation rate by tuning the mass transfer across the membrane.Variations of the transmembrane flux and supersaturation rate imply modifications in thedriving force by acting on operative temperature and solution composition (e.g. solutionconcentration). These parameters can be controlled in time during the crystallization, sothat the state of the substance studied moves along a well-defined kinetics trajectory in thephase diagram.

References:[1] H.N. Chapman, Synchrotron Radiation News, 28, (2015), 20.

[2] M.P. Blakeley, S.S. Hasnain, S.V. Antonyuk, IUCrJ, 2, (2015), 464.[3] M. Budayova-Spano, F. Dauvergne, M. Audiffren, T. Bactivelane, S. Cusack, Acta Cryst. D., D63, (2007),

339.

[4] M. Budayova-Spano, Patent FR10/57354, UJF, (extension : EP117730945, US13821053, JP2013528746),(2010).

[5] N. Junius, E. Oksanen, M. Terrien, C. Berzin, J.L. Ferrer, M. Budayova-Spano, J. Applied. Cryst., 49,(2016), 806.

[6] M. Budayova-Spano, N. Junius, J.B. Salmon, Patent FR2016/053185, (2016).

Solvent Behavior, Ice Formation, and Nanoconfinement inProtein Crystals: Implications for Cryo- and Variable-Temperature CrystallographyRobert E. Thorne1, David W. Moreau1, and Hakan Atakisi1

1Physics Department, Cornell University, Ithaca, NY 14853 USA

Ice formation within protein crystals is a major obstacle to cryocrystallographic study ofprotein structure, and has limited studies of how a protein’s structural ensemble evolveswith temperature in the biophysically interesting range from ~260 K to the protein-solventglass transition near 200 K. Using protein crystals having solvent cavities as large as ~70Å, we use time-resolved X-ray diffraction to study the response of protein and internalsolvent during rapid cooling. Solvent nanoconfinement suppresses freezing temperaturesand ice nucleation rates so that ice-free, low mosaicity diffraction data can be reliablycollected down to 200 K without use of cryoprotectants. Solvent expulsion from unit cellsduring cooling creates disorder, but subsequent protein relaxation and solvent flow at

can lead to dramatic reordering. Hexagonal ice (Ih) forms in external solvent, butinternal crystal solvent forms stacking disordered ice (Isd) with a near random stacking ofcubic and hexagonal planes. Analysis of powder diffraction from internal ice and singlecrystal diffraction from the protein lattice shows that the maximum crystallisable solventfraction decreases with decreasing crystal solvent cavity size, and that a ~5 Å thick layer ofsolvent adjacent to the protein surface cannot crystallize. These results establish proteincrystals as excellent model systems for study of nanoconfined and supercooled solvent.By combining intense X-ray beams, fast detectors, and fast cooling, they enable highresolution, variable temperature structural studies of high-solvent content and large unit cellbiomolecular crystals – including those of membrane proteins and large complexes - undernative-like conditions.

Figure.1. Solvent cavity structure in (a) cubic apoferritin,(b) tetragonal thaumatin, and (c) tetragonal lysozyme.Solvent spaces within the first and second hydrationshells are shown in dark blue and medium blue,respectively.

MS#7

Hybrid methods in structural biology

Molecular dynamics gives insights into TetR transcriptionalregulator functionDawes, Stephanie1; Razzak, Ali1; Shadfar, Shamim1; Ho, Ngoc An Thu1,2; Allison, Jane1;Lott, J. Shaun1

1School of Biological Sciences and Maurice Wilkins Centre for Molecular Biodiscovery,School of Biological Sciences, The University of Auckland, New Zealand.

2School of Physical and Chemical Sciences and The Biomolecular Interaction Centre,University of Canterbury, New Zealand.

The TetR family of transcriptional regulators is widespread in bacteria. They regulatebiological processes such as multidrug resistance, biofilm formation, biosynthesis ofantibiotics, catabolic pathways, nitrogen fixation, and stress responses amongst others,and as such are often important for pathogenicity. Members of the family have beentargeted for drug development, but due to the huge variety within the family, defining theallosteric components of the mechanism of each is necessary and time-consuming. KstRand KstR2 are two TetR family repressors that regulate cholesterol metabolism inMycobacterium tuberculosis and other actinomycetes. KstR is essential for pathogenesis inM. tuberculosis and is a candidate for drug development. The crystal structures of both ofthese regulators have been solved in apo form and in complex with their cognate ligands,and a different allosteric mechanism for each has been proposed based on the crystalstructures. We show that the molecular dynamics simulations can segue between thevarious poses determined by X-ray crystallography, and provide key insights into some ofthe various allosteric mechanisms supported by this diverse family of proteins.

A tale of two proteases: Using X-rays to dissect the function of novel bacterial ferroprotein degradases. Rhys Grinter1 and Trevor Lithgow1 1Monash University, Melbourne, Australia

In order to obtain the iron required for growth during infection, gram negative bacteria have evolved systems to obtain iron directly from host proteins [1]. The recently identified Ferredoxin uptake system from the plant pathogen Pectobacterium targets host ferredoxin. The transporter component of the system ‘FusA’ binds ferredoxin at the bacterial cell surface and transports it across the bacterial outer membrane [2]. Once inside the bacterial cell, ferredoxin is processed by the protease FusC, cleaving the ferredoxin and releasing its iron cofactor [3]. In our current work, we have determined the structural basis for processing of ferredoxin by FusC. We have determined the crystal structure of FusC in complex with ferredoxin, and dissected their interactions in solution using small angle X-ray scattering (SAXS) and complementary biophysical techniques. These data show that FusC forms a dynamic, partially closed clam shell structure, which binds ferredoxin in its internal cavity and induces partial unfolding [4]. This unfolding allows FusC to cleave ferredoxin at two distant locations and represents a highly novel mechanism for this family of protease. In addition, we have analysed the FusC homologue from Escherichia coli, the unknown-ferroprotein degradase PqqL. SAXS analysis and the crystal structure of PqqL shows that it adopts an entirely open conformation in solution, suggesting that this family of ferroprotein degradase undergoes significant conformational rearrangement upon substrate binding. 1. Skaar EP. The Battle for Iron between Bacterial Pathogens and Their Vertebrate Hosts. PLoS Pathog. 2010;6(8):e1000949. doi: 10.1371/journal.ppat.1000949. 2. Grinter R, Josts I, Mosbahi K, Roszak AW, Cogdell RJ, Bonvin AM, et al. Structure of the bacterial plant-ferredoxin receptor FusA. Nat Commun. 2016;7. 3. Mosbahi K, Wojnowska M, Albalat A, Walker D. Bacterial iron acquisition mediated by outer membrane translocation and cleavage of a host protein. Proceedings of the National Academy of Sciences. 2018:201800672. 4. Grinter R, Hay ID, Song J, Wang J, Teng D, Dhanesakaran V, et al. FusC, a member of the M16 protease family acquired by bacteria for iron piracy against plants. PLoS Biol. 2018;16(8):e2006026.

Investigation of an ABC transporter MsbA in stealth carriernanodiscs using small angle scattering techniquesJosts, Inokentijs1; Nitsche, Julius1; Maric, Selma2; Mertens, Haydyn D.3; Moulin, Martine4;Haertlein, Michael4; Prevost, Sylvain4; Svergun, Dmitri I.3; Busch, Sebastian6; Forsyth,Trevor V.4,5; Tidow, Henning1

1 The Hamburg Centre for Ultrafast Imaging & Department of Chemistry, Institute forBiochemistry and Molecular Biology, University of Hamburg, Martin-Luther-King-Platz 6,20146 Hamburg, Germany

2 Biofilms- Research Center for Biointerfaces, Department of Biomedical Science, Facultyof Health and Society, Malmö University, Malmö 20506, Sweden

3 European Molecular Biology Laboratory Hamburg, Notkestrasse 85, 22607 Hamburg,Germany

4 Life Sciences Group, Institut Laue–Langevin, 6 Rue Jules Horowitz, 38042 Grenoble,France

5 School of Life Sciences, Keele University, Staffordshire ST5 5BG, England

6 German Engineering Materials Science Centre (GEMS) at Heinz Maier-Leibnitz Zentrum(MLZ), Helmholtz-Zentrum Geesthacht, Lichtenbergstr. 1, 85747 Garching bei München,Germany

Structural and biophysical characterisation ofintegral membrane proteins is often challengingdue to the need of highly homogeneous andstable samples. To achieve this, membraneproteins are extracted from their native complexlipid bilayer environment using detergents, whichin turn could lead to increased sampleheterogeneity and poor stability. In recent years,the development of novel methodologies suchas reconstitution of membrane proteins intonanodisc scaffolds laden with lipids has helpedovercome numerous challenges associated withthe handling and stability of membrane proteins.The advantage of the nanodisc systems is thatthey provide a native lipid-like environment forthe embedded membrane protein in solution. Inthis study, we have used fractionally deuteratedscaffold protein MSP1D1 as well as deuteratedlipids to assemble “stealth carrier” nanodiscs which are essentially invisible to neutronradiation at 100% D2O. Successful incorporation of an ATP-binding cassette (ABC)transporter MsbA from Escherichia coli into these stealth nanodiscs has enabled us to carryout small angle neutron scattering experiments where the observed scattering signalcomes exclusively from the incorporated MsbA protein without the contribution from theMSP1D1 belt protein nor the surrounding lipids. Through the joint use of neutron and X-rayscattering techniques we were able to describe the overall conformation of MsbA in solutionas well as transitions between various conformational states of this ABC transporter. Webelieve this approach can be highly advantageous for studying dynamic and flexiblemembrane proteins in a native-like lipid environment.

Structural Function Studies of Complement Component-9Spicer, Bradley1; Law, Ruby1; Caradoc-Davies, Tom2; Ekkel, Sue1; Bayly-Jones, Charlie1;Pang, Siew-Siew1; Conroy, Paul1; Ramm, Georg1; Radjainia, Mazdak3; Venugopal, Hari1;Whisstock, James1 and Dunstone, Michelle1

1Biomedicine Discovery Institute, Department of Biochemistry and Molecular Biology,Monash University, VIC 3800 Australia2Australian Synchrotron, 800 Blackburn Road, Clayton, Melbourne, Australia, 31683FEI Achtseweg Noord 5, Building 5651 GG Eindhoven, The Netherlands

Complement component 9 (C9) is the pore-forming component of the Membrane AttackComplex (MAC). During MAC assembly, multiple copies of C9 are sequentially recruited tothe C5b8 complex (the nascent MAC) to form a large transmembrane pore.

Currently, however, the molecular mechanism that drives MAC assembly, and that preventsspontaneous C9 oligomerisation in the absence of C5b8 remains unclear. Here weaddress these questions by determining the 2.2 Å X-ray crystal structure of monomeric C9and the 3.9 Å resolution cryo EM structure of C9 in a polymeric assembly.

Structural comparisons between these two C9 conformers reveals an unexpected findingthat the first transmembrane region (TMH1) is uniquely positioned on the monomeric formof C9 as compared to other MAC proteins. In this position, it functions to sterically inhibit C9self-assembly in the absence of C5b8. Our biochemical data further reveal that followingrecruitment to C5b8, a conformational change in TMH1 is essential for the unidirectionaland sequential addition of C9 monomers to the assembly1.

This mechanism of assembly is in direct contrast to other members of the MAC / Perforin /Cholesterol Dependent Cytolysin superfamily, where it is currently believed that pre-poreassembly is bi-directional and occurs prior to the release of transmembrane regions.

1Spicer and Law et al., 2018 The X-ray crystal structure of Complement component-9 reveals that the first

transmembrane region acts as a brake on self-assembly. Nature Comm. Article number 3266.

Lattice nano-ripples revealed in peptide microcrystals byscanning electron nanodiffractionMarcus Gallagher-Jones1, Colin Ophus2, Karen C. Bustillo2, David R. Boyer1, OulianaPanova2,3, Calina Glynn1, Chih-Te Zee1, Jim Ciston2, Kevin Canton Mancia1, Andrew M.Minor2,3, and Jose A. Rodriguez1

1 Department of Chemistry and Biochemistry, UCLA-DOE Institute for Genomics andProteomics, University of California Los Angeles, Los Angeles, CA 90095, USA.2National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley NationalLaboratory, CA, USA.3 Department of Materials Science and Engineering, University of California Berkeley, CA,USA.

Changes in lattice structure across sub-regions of protein crystals are challenging toassess when relying on whole crystal measurements. Because of this challenge,macromolecular structure determination from protein micro and nano crystals relies onassumptions of bulk crystallinity and domain block substructure. To assess changes inlattice structure within protein nanocrystals, we map diffraction from sub-10nm areas ofcryogenically preserved three-dimensional peptide crystals by scanning a focused electronbeam across a crystal. This approach produces diffraction from as few as 1,500 molecules,is sensitive to crystal thickness and is descriptive of three-dimensional lattice orientationacross whole microcrystals. Real-space maps reconstructed from unbiased clustering oftwo-dimensional diffraction scans reveal regions of crystal order/disorder and three-dimensional lattice reorientation on a 20nm scale. The lattice changes measured in thesepeptide nanocrystals provide a direct view of the plasticity present in macromolecular

crystals.

Figure.1. Measuring lattice structure in peptide nanocrystals by 4D Scanning Transmission ElectronMicroscopy.

Integrative Structural Investigation on Macromolecular ProteinComplexes

Ji-Joon Song

Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST),Daejeon 34141, Korea

Proteins in cells form multi-subunit protein complexes. It is imperative to investigate the

structures of the complexes as a whole to understand molecular mechanisms of the

complex. However, it has been challenging to investigate large protein complexes. Here, I

have investigated large protein complexes including histone nuclear importin complex and

Huntington’s disease protein through an integrative structural approach including X-ray

crystallography, electron microscopy, small X-ray scattering and integrative modeling. I will

discuss the strategy to investigate large protein complexes through an integrative structural

approach.

MS#8

Structure and properties of functional

materials

Evolution of Form in Metal-Organic FrameworksChoe, Wonyoung1

1Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST),Ulsan, Korea

Structural control in metal-organic frameworks (MOFs) is an important issue because asubtle change can make big differences in properties. For the past two decades, MOFchemists have developed a wide range of synthetic strategies for MOFs and related porousmaterials, to control crystal structures of MOFs. In this presentation, we show a newsynthetic approach to control both interior and exterior of MOF materials. We expect thatthe resulting MOFs, such as hollow, double-hollow , and core-shell types, together withtriangular patterned ones, will be useful in many applications including heterogeneoustandem catalysis and metamaterials.

Finding the atoms that matter in functional materialsEtheridge, Joanne1

1Monash Centre for Electron Microscopy and Dept of Materials Science and Engineering,Monash University, VIC 3800, Australia.

It is often departures from perfect periodicity that give a material its distinctive properties.When these departures occur at the atomic scale, they can be particularly challenging todetect and measure, making it difficult to correlate structure with properties. In modernelectron microscopes, electron wave fields can be crafted into tiny structured probes thatcan target and ‘interrogate’ small numbers of ‘chosen’ atoms providing specific informationabout the atoms that may be controlling the properties of a material. This talk will describethe development and application of new electron scattering methods for determining localstructure. It will illustrate these with applications to determine structure-propertyrelationships in a range of functional materials, including perovskites for battery and solarcell applications, semiconducting nanostructures and metallic nanoparticles for controllinglight.

Effect of local structure variation on Photo-catalytic Organic Transformation activity of Iso-structural PbW1-xMoxO4 Nano-solid Solutions Halappa, Pramod1; Neuefeind, J. C 2; Plaiser, J3; Shivakumara, C1. 1Solid State and Structural Chemistry Unit, Indian Inst. of Science, Bangalore, India 2Chemical and Engineering Materials Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA 3MCX Beamline, Elettra Synchrotron Facility, Area Science Park, Basovizza, Trieste, Italy

Over the years, much attention has been paid to the use of light driven chemical reactions because it can easily perform chemical transformation following a ‘‘green’’ synthetic route. Heterogeneous photocatalysis has been believed, to be a dream technology for solving energy and/or environmental problems that we are facing [1-3]. The single phase iso-structural materials PbW1-xMoxO4 (x = 0, 0.25, 0.5, 0.75, 1) was synthesized by Hydrothermal method. Synchrotron powder X-ray diffraction studies confirmed that PbW1-xMoxO4 (x = 0, 0.25, 0.5, 0.75, 1) solid solutions were crystallized in the scheelite tetragonal structure with space group I41/a (No. 88). Rietveld refinement has been carried out using GSAS-EXPGUI suite on these nanoparticles using synchrotron X-ray data (Elettra Synchrotron facility, Trieste, Italy). Structures are refined in the I41/a space group using the PbWO4 as model. The average crystallite size and morphology of PbW1-xMoxO4 solid solutions were observed by TEM and respectively. By using high Q Spallation Neutron diffraction data (NOMAD, ORNL, USA), the local structures of these solid solutions were evaluated through atomic pair distribution function (PDF) analysis using PDFgui program from Finally photo catalytic organic conversion activity was observed for PbW1-xMoxO4 (x = 0, 0.25, 0.5, 0.75, 1) catalysts. UV-DRS measurements for band gap analysis and Raman studies were also carried out. The efficient conversion from Nitrobenzene to aniline was observed for PbW0.5Mo0.5O4 catalyst compared to PbMoO4 and PbWO4, nano-catalysts under UV light irradiation. The evaluated Structural disorderness or variations were correlated with enhanced phocatalytic activity of these solid solutions. The overall aspects of present study reveals that, these single phase nano solid solutions are promising candidates for future energy harvesting and environmental remedy applications.

References: [1] Bunsho Ohtani, Revisiting the fundamental physical chemistry in heterogeneous photocatalysis: its thermodynamics and kinetics. Phys.Chem.Chem.Phys., 2014, 16, 1788. [2] Horst Kisch, Semiconductor Photocatalysis—Mechanistic and Synthetic Aspects. Angew. Chem. Int. Ed. 2013, 52, 812 – 847. [3] Ioana Fechete, et.al,, The past, present and future of heterogeneous catalysis. Catalysis Today, 2012, 189 (2), 27-53.

Crystallographic understanding of proton conducting pathwaywith conducting medium confined in metal-organic frameworksLim, Dae-Woon1, Kitagawa, Hiroshi1,*

1Division of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan

Solid-state proton conductors (SSPCs) have received a great attention due to theirapplications in electrochemical devices such as sensor and fuel cell. Typically, aconventional organic polymer, nafion, is a well-known SSPC material exhibiting a highproton conductivity (> 10-2 S cm-1) under the high humidity and mild temperature range (<85 oC). However, its amorphous phase makes it difficult to understand the conductionpathway.

Metal-organic frameworks are emerging as a potential SSPC because of their highcrystallinity, chemical tunability, considerable porosity, and versatile adsorption. Theoverwhelming MOF proton conductors contain water molecules in the pore as a conductingmedium, in which proton diffusion mechanisms through the hydrogen bonding network arewell established by numerous experimental and theoretical studies, whereas NH3, exhibitingthe most similar molecular system to water, has scarce information as a proton conductingmedium in MOFs because its corrosive gas phase is detrimental in MOF compounds. Inaddition, NH3 is able to coordinate to metal ions through the replacing the existing ligandresulting in the deconstruction of frameworks. Therefore, it is challenging to understand theconducting pathway of NH3 mediated MOF proton conductors. Herein, we report theammonia (NH3) mediated-MOF proton conductors with crystallographic analysis. We founda significant enhancement of proton conductivity through NH3 adsorption. The plausibleconduction mechanism (diffusion pathway) and the dynamic behavior of confined ammoniawere investigated by structure analysis and 2H NMR measurement.

Figure.1. Crystal structure of NH3 loaded MOF.

The Effect of K-doping on the Performance of P2-type Na-ion Battery Cathode Materials Pierre Naeyaert1, Maxim Avdeev2, Neeraj Sharma3 and Chris D. Ling1 1 School of Chemistry, The University of Sydney, Sydney 2006, Australia. 2 ANSTO, Locked Bag 2001, Kirrawee DC NSW 2232, Australia 3 School of Chemistry, The University of New South Wales, Kensington NSW 2052, Australia Since lithium-ion batteries were commercialized in 19911, they have dominated the portable electronics market. In 2017, 39% of the world’s mined lithium was devoted to lithium-ion battery applications2. Increased future demand will be driven by the electric/hybrid vehicle market and load levelling solutions for renewable energy sources3. Therefore, the development of new, low-cost alternatives to lithium-ion batteries with comparable electrochemical properties is highly desirable. Sodium is the most obvious choice, as an inexpensive, abundant, and easily extractable element. Deployed on a large scale, they could provide energy storage solutions to mitigate against the intermittent nature of renewable energy generation. However, viable commercial Na-ion batteries remain elusive, with new electrode materials and electrolytes being required. The Na(Fe,Mn)O2 phases, which are among the leading contenders for positive electrode materials, show an array of structural subtleties that are intricately linked to the electrochemical performance. We have investigated the P2-type Na2/3Fe2/3Mn1/3O2 phase. Under electrochemical cycling this P2 phase has been reported to undergo substantial unit cell variations and a phase transitions, decreasing the reversible capacity of the electrode material. This has been previously overcome by lowering the high voltage cut off point, but at the expense of reduced electrochemical performance. We have synthesised a K-doped P2 polymorph of the composition K0.16Na0.66Fe2/3Mn1/3O2. The K-doped phase shows significantly improved capacity retention compared with the undoped parent material (Table 1). In situ XRD under electrochemical cycling, ex situ solid state NMR and differential capacity analysis indicate that the presence of K in the electrode prevents high voltage phase changes, allowing for a more structurally reversible mechanism to be achieved, in turn leading to improved electrochemical performance.

Table.1. Capacity retentions after 15 cycles at various voltage cut-offs. [1] Kim, S. W.; Seo, D. H.; Ma, X. H.; Ceder, G.; Kang, K. Adv. Energy Mater. 2012, 2, 710. [2] U.S. Geological Survey, 2017; 100 pp. [3] Ellis, B. L.; Nazar, L. F. Curr. Opin. Solid State Matter. 2012, 16,168. [4] B. Mortemard de Boissea,b, D. Carliera,b,z, M. Guignarda,b and C. Delmas. J.

Electrochem. Soc. 2013, 25, 142.

High voltage cut-off Phase Capacity retention after 15 cycles

Charge to 4.2 V K0.16Na0.66Fe2/3Mn1/3O2 75.0 % Na0.66Fe2/3Mn1/3O2 63.7 %

Charge to 4.3 V K0.16Na0.66Fe2/3Mn1/3O2 73.1 % Na0.66Fe2/3Mn1/3O2 52.1 %

Charge to 4.5 V K0.16Na0.66Fe2/3Mn1/3O2 74.8 % Na0.66Fe2/3Mn1/3O2 32.0 %

Crystal structure and organocatalyst properties of two new alkylthiourea derivativesAaina Mastura Azman1, Syarifah Mansuriana Tuan Mansor1, Maisara Abdul Kadir andMohd Sukeri Mohd Yusof1*

1School of Fundamental Science, Universiti Malaysia Terengganu, 21030 Kuala Nerus,Terengganu, Malaysia

Organocatalyst is referred as organic molecule that acts as catalyst in the reaction. Thistype of catalysts is favoured due to their green and sustainable properties. Therefore, alongwith this interest, we have developed two new alkyl thiourea derivatives, namely N-((5-chloro-2-phenoxyphenyl)carbamothioyl)propionamide (A1) and N-((5-chloro-2-phenoxyphenyl)carbamothioyl)butyramide (A2). Compound A1 crystallized in triclinic, P-1have two molecules in asymmetric unit while A2 crystallized in monoclinic, P21/n, andmonomeric. Both of the compounds have identical geometries which only vary at bondlengths and angles. The performance of A1 and A2 was tested as organocatalyst inMichael addition reaction of N-phenylmaleimide and isobutyraldehyde using GasChromatography-Flame Ionization Detector (GC-FID). Under optimum condition, catalystA1 gave 67 % of yield while A2 gave 70 % yield of product.

Figure.1. The ORTEP diagram of A1 with 50% probability level.

MS#9

XFELs and serial crystallography

SPB/SFX: First Experimental Results and Future DevelopmentsBean, Richard1; on behalf of the SPB/SFX instrument group

1European XFEL GmbH, Hamburg, Germany

The Single Particle, Biomolecules and Clusters & Serial Femtosecond Crystallographyinstrument (SPB/SFX) at the European XFEL is designed primarily for biological singleparticle and protein crystallography experiments. The instrument allows users to takeadvantage of the huge increase in x-ray pulse rate and the unique x-ray pulse structure ofthe European XFEL at energies . SPB/SFX was one of the first two instruments to startuser experiments at the European XFEL in September 2017. The instrument will bedescribed including the key components for sample delivery, the AGIPD detector and x-raybeam conditioning.

Experiments at the SPB/SFX instrument are producing encouraging results, and two recentpublications from the early user phase have shown that currently available methods ofsample delivery can take advantage of the MHz x-ray pulse rate [1,2], so far up to 120pulses per train at 1.1 MHz. These SFX experiments successfully recorded crystallinediffraction without any apparent loss of data quality or rate across the pulse train andresulted in new structures submitted to the PDB. The first small angle diffraction andsolution scattering experiments have also recently been completed.

Future developments at the instrumentwill be highlighted including a 100nmscale KB mirror focus, sampleenvironment developments, and theinstallation of the second(downstream) interaction region.

[1] Wiedorn et al. Nat. Comms. 9, 4025 (2018)

[2] Grünbein et al. Nat. Comms. 9, 3487 (2018)

Figure.1. Impression of the layout of the SPB/SFX

instrument and the upstream interaction chamber

(insert).

The effect of consecutive X-ray pulses on a single crystal at the European XFEL Holmes, Susannah1; Barty, A2; Chapman, H2,3,4; Kirkwood, H5; Kobe, B6; Nugent, K1; White, T2; Wiedorn, M2,3,4; Mancuso, A5; Oberthür, D2; Martin, A7; Darmanin, C1; Abbey, B1 1Australian Research Council (ARC) Centre of Excellence in Advanced Molecular Imaging, Department of Chemistry and Physics, La Trobe Institute for Molecular Sciences, La Trobe University, Bundoora, VIC 3086, Australia. 2 Center for Free Electron Laser Science, Deutsches Elektronen Synchrotron 3 Department of Physics, University of Hamburg 4 Center for Ultrafast Imaging, University of Hamburg 5 European XFEL GmbH 6 School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland 7 RMIT University

Multiple diffraction images arising from a single Lysozyme crystal have been observed at the European X-ray free-electron laser (XFEL). Observing this multiple diffraction phenomenon has previously been limited by the slower pulse repetition rates (120 frames/second or 8 millisecond pulse spacing) available at other XFEL facilities 1,2,3. At the European XFEL (EuXFEL), a pulse repetition rate of 1.1 MHz was performed, allowing for a pulse spacing of less than one microsecond 4. With this pulse spacing, it was possible to observe single Lysozyme crystals hit by consecutive X-ray pulses at various speeds. Analysing the Lysozyme data and beam shape, information on crystal location at the time of the X-ray pulses was estimated. Little to no resolution loss was seen when comparing Lysozyme crystals hit by a single pulse versus those hit by multiple pulses. Therefore, we show that it is acceptable to include diffraction data from crystals hit multiple times for structural determination. Furthermore, as little to no resolution loss is seen, future experiments could possibly utilise this phenomenon in order to minimise crystal consumption.

References 1 Ishikawa, T. et al. A compact X-ray free-electron laser emitting in the sub-ångström region. Nat Photonics 6, 540–544 (2012). 2 Yabashi, M., Tanaka, H. & Ishikawa, T. Overview of the SACLA facility. J. Synchrotron Rad (2015). 22, 477-484 [doi:10.1107/S1600577515004658] 1–8 (2015). doi:10.1107/S1600577515004658. 3 White, W. E., Robert, A. & Dunne, M. The Linac Coherent Light Source. J. Synchrotron Rad (2015). 22, 472-476 [doi:10.1107/S1600577515005196] 1–5 (2015). doi:10.1107/S1600577515005196. 4 Altarelli, M. & Mancuso, A. P. Structural biology at the European X-ray free-electron laser facility. Philosophical Transactions of the Royal Society B: Biological Sciences 369, 20130311–20130311 (2014).

Time-Resolved XFEL Crystallography for Capturing ReactionIntermediates of Respiratory MetalloenzymesKubo, Minoru1

1Graduate School of Life Science, University of Hyogo, Japan

Time-resolved (TR) crystallography using X-ray free electron lasers (XFELs) is beingestablished and increasingly applied to proteins for visualizing their structural dynamics as"molecular movies". Using SACLA, we have applied this technique to two respiratorymetalloenzymes, bovine cytochrome c oxidase (CcO) and fungal NO reductase (P450nor).

CcO is the terminal oxidase of cell respiration that catalyzes O2 reduction to H2O at theheme-cupper center, coupled with proton pump across the mitochondrial inner membrane.In this study, the structural dynamics of CcO following CO ligand photo-dissociation fromthe heme was investigated, using pump-probe TR-SF-ROX. TR-IR microspectroscopy wasalso preformed to monitor the CO ligand kinetics in the crystalline phase. As a result, wesuccessfully observed the dynamic gate opening process in the putative proton-pumppathway, triggered by CO dissociation from the cupper site in the µs time domain [1].

P450nor is a heme enzyme that catalyzes NO reduction to N2O in the anaerobic respirationin the fungal mitochondria. To track the enzymatic reaction, a caged substrate (caged NO)was used as a reaction trigger in the pump-probe TR-SFX experiment. The reactionkinetics in the crystalline phase was assessed by TR-visible microspectroscopy. Althoughthe crystal packing affects the reaction rate, we captured NO binding to the heme at 20 msafter the caged-NO photolysis [2]. This study demonstrates the utility of caged compounds,which will expand the applications of TR crystallography for dynamic structural analyses ofvarious enzymes.

References: [1] Sci. Adv. 3, e1603042 (2017). [2] Nat. Commun. 8, 1585 (2017).

Development of fixed-target serial synchrotron crystallographyat room temperature in SPring-8Kumasaka, Takashi1; Hasegawa, Kazuya1; Baba, Seiki1; Kawamura, Takashi1; Yamashita,Keitaro2; Hirata, Kunio3; Yamamoto, Masaki3

1Japan Synchrotron Radiation Research Institute (JASRI)2The University of Tokyo3RIKEN SPring-8 Center

The serial femtosecond crystallography (SFX) developed at XFELs opened a newparadigm for MX data collection and successfully applied to the time-resolved (TR)analysis. Its success leads to establish synchrotron serial crystallography (SSX) bycombining a high-flux microbeam and a fast-readout detector. And then SSX is going toevolve to TR-SSX, also called as serial millisecond crystallography (SMX). Most SMXmethods are almost compatible to TR-SFX by using apparatuses developed at XFELs. It isuseful to examine both methods and light sources, but some high barriers remain inapproach from the conventional MX method.As an alternate way to TR analysis, we propose to apply a capillary free mount technique,which can apply various experimental conditions, to SMX. It's our improved method, HAG(humid air and glue-coating) method, has more suitable features for room temperatureSMX: it maintains most samples, which are fixated to cryoloops by glue [1]. It has alreadyrevealed the dynamical motions of H-Ras [2], cytochrome c oxidase [3] and so on. We arenow combining it to SSROX, our improved SSX [4], as a fixed-target SMX. Thisdevelopment is being conducted at SPring-8 BL41XU, where the pink beam will beavailable in future. Conclusively, we have been totally engaged in the development of serialcrystallography by using both SPring-8 micro-focus beamlines and XFEL SACLA.[1] Baba et al., Acta Cryst D69, 1839 (2013); [2] Matsumoto et al., Sci Rep 6, 25931 (2016);[3] Shimada et al., Sci Adv 3, e1603042 (2017); [4] Hasegawa et al., J Sync Rad 24, 29(2017)

Fluctuation x-ray scattering: measuring local 3D structure ofamorphous materials, liquids and nanocrystals.Martin, Andrew V.1,2

1School of Science, RMIT, Victoria, Australia2ARC Centre of Excellence for Advanced Molecular Imaging

The isotropic scattering of disordered materials is commonly measured by techniques suchas small-angle x-ray scattering or powder diffraction to characterize the local or molecularstructure. Although these techniqes are highly popular and in wide use, they provide alimited 1D structural characterization (the well-known pair-distribution function). Lesscommonly known is that weak anisotropic fluctuations of the intensity carry 3D informationin the form angular distribution functions. The angular information can potentially bemeasured with small, intense x-ray beams provided by x-ray free-electron lasers or withhighly focused electron beams. There is a growing interest, for example, in exploitingintensity fluctuations for the determination of protein structure with x-ray lasers. We havetaken a different approach. Our recent theory provides the structural interpretation ofintensity fluctuations for continuous disordered systems (liquids, amorphous materials) witha natural generalization of the 1D pair-distribution function to 3D angular distributions ofthree- and four-body statistics. The angular distribution contains, for example, bond angledistributions. We present the background theory and show experimental demonstrationswith electrons to amorphous solids and with x-rays to soft-matter and liquid systems.

New opportunities for structural biology research at LCLSand SSRLSmith, Clyde1,2, Cohen, Aina1, Lyubimov, Artem1,2, Russi, Silvia1, Wierman, Jennifer1,2,Hodgson, Keith1,2.

1SSRL Structural Molecular Biology, SLAC National Accelerator Laboratory, Menlo Park,CA 94025, USA.

2Department of Chemistry, Stanford University, Stanford, CA 94305, USA

Femtosecond crystallography (FX) is an emerging method that expands the structuralinformation accessible from very small or very radiation sensitive macromolecular crystals.Utilizing extremely bright, short-time-scale X-ray pulses produced by X-ray free electronlasers (XFELs), this method exploits a “diffraction before destruction” phenomenon where astill diffraction image is produced by a single X-ray pulse before significant radiationinduced electronic and atomic rearrangements can occur. This data collection methodologyconfronts a major challenge impeding progress in structural enzymology by providing ameans to determine catalytically accurate structures of acutely radiation sensitivemetalloenzymes. A diffractometer-based experimental setup for FX experimentation isavailable to general users at the new Macromolecular Femtosecond Crystallography (MFX)instrument of the LCLS XFEL. This instrument is based on developments at SSRL andLCLS-XPP to provide an efficient framework to carry out goniometer-based FX experimentsusing automated strategies tailored to handle a variety of sample requirements, crystalsizes and experimental goals. Various sample delivery and data acquisition systems areimplemented including grids, meshes, loops, injectors (Figure 1A), room temperaturecollection and humidity control, and in-situ spectroscopic monitoring. These developmentscoupled with improvements in data processing algorithms make it possible to derive highresolution crystal structures using only 100 to 1000 still diffraction images. Similarities ininstrumentation, existing and new sample delivery systems, and software environments willform the foundation of a synergistic relationship between the LCLS-MFX instrument andthe newly-built microfocus beamline BL12-1 at SSRL (Figure 1B), through a unified

gateway approach.

Figure 1. (A) Sample delivery methods (clockwise from top left); the MESH injector, microfluidic trap, fixed-target grids and loops, and the LCP injector. (B) The new microfocus beamline BL12-1 at SSRL.

MS#10

Disease-related proteins

Using Structural Biology as a tool to Decipher Origins ofAntibiotic ResistanceRuchi Anand1

1Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, India, 400076:Email: ruchi@chem.iitb.ac.in

Antibiotic resistance is a silent epidemic which has risen to alarming proportions. It isprojected that by 2050 drug resistance will result in more than 300 million deaths. Bacteriaof the Streptomyces genus that produce 70% of the commercially available antibiotics areuniquely placed as they possess mechanisms to not only resist antibiotics but also havethe ability to produce them. These Streptomyces species possess the most evolvedresistance machineries as they are under constant pressure to protect themselves from theantibiotics they produce. Two major strategies adopted by these organisms are firstly toreduce the levels of the antibiotic via efflux and second to modify the target site of theantibiotics, the ribosome, thereby making these drugs ineffective. Here, we discuss boththese mechanisms and explore the origins of antibiotic resistance via firstly developingstructural and mechanistic insights into the tetracycline receptors (TetRs) efflux regulatorsfrom varied Streptomyces species. A series of X-ray structures in the apo and DNA boundform help decipher the conformational changes and elements that play a key role inrecognition and in allosteric modulation of the these TetRs1,2,3.Second focus is on specificityand targeting mechanism of methylation by ribosomal methyltransferases that covalentlymodify ribosomes and thereby, do not allow antibiotics to bind. This epigenetic methylationof RNA predominately occurs via an S-adenosine methionine (SAM) dependent catalyticroute. These methlyases (Mtases) although harbour a common rossman fold, exhibitalmost no cross reactivity. Here, in order to delineate the specific targeting determinantsthat impart substrate specificity to Mtases, by employing a combination of evolutionary andstructure guided approaches a set of protein chimeras were created where, the targetingspecificity of KsgA a ribosomal methytransferase involved in biogenesis was switched toerthyromycin dependent methyltransferase (erm), a rMtase found in pathogens,responsible for imparting aggressive resistance against the macrolide class of antibiotics.The results reveal that specific loop embellishments on to the basic rossman fold are themajor determinants that aid in selection and in stabilization of the correct RNA into to theactive site. Moreover, invivo studies confirm that chimeric version of the protein arecompetent in imparting macrolide resistance. Overall, this work not only provides insightsinto the strategies adopted by nature that govern specificity but additionally serves as astepping stone to aid in development of specific inhibitors that can combat antibioticresistance

1. Biswas, A., Swarnkar, R. K., Hussain, B., Sahoo, S.K., Pradeepkumar, P.I., Patwari, G.N., Anand, R.;J Phys Chem B. 2014; 118(34):10035-42

2. Bhukya, H., Bhujbalrao, R., Bitra, A., Anand, R.;; Nucleic Acids Res. 2014; 42(15):10122-33

3. Ray S, Maitra A, Biswas A, Panjikar S, Mondal J, Anand R; J Biol Chem. 2017, Sep15;292(37):15301-15311

Structural Insights into the Gating of DNA Passage by theTopoisomerase II DNA-Gate

Chen, Shin-Fu1, Huang, Nan-Lan2,3, Lin, Jung-Hsin2, Wu, Chyuan-Chuan1,4, Wang, Ying-

Ren1, Yu, Yu-Jen1, Gilson, Michael K.3 & Chan, Nei-Li1,5

1Institute of Biochemistry and Molecular Biology, College of Medicine, National TaiwanUniversity, Taipei, Taiwan.2Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan.3Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, SanDiego, La Jolla, CA.4Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan.5Scientific Research Division, National Synchrotron Radiation Research Center, Hsinchu,Taiwan.

Type IIA topoisomerases (Top2s) manipulate the handedness of DNA crossovers byintroducing a transient and protein-linked double-strand break in one DNA duplex, termedthe DNA-gate, whose opening allows another DNA segment to be transported through tochange the DNA topology. Despite the central importance of this gate-opening event toTop2 function, the DNA-gate in all reported structures of Top2-DNA complexes is in theclosed state. In this study, we have obtained the crystal structure of a human Top2 DNA-gate in an open conformation, which not only reveals structural characteristics of its DNA-conducting path, but also uncovers unexpected yet functionally significant conformationalchanges associated with gate-opening. This structure further implicates Top2’s preferencefor a left-handed DNA braid and allows the construction of a model representing the initialentry of another DNA duplex into the DNA-gate. Using this structure as a starting point,steered molecular dynamics calculations suggest that the Top2-catalyzed DNA passagemay be achieved by a rocker-switch-type movement of the DNA-gate. Given that the Top2DNA-gate is the target of regulatory proteins and a group of anticancer and antibacterialdrugs, this work also is of direct medical relevance.

Antibacterial drug resistance through ribosome protection ATP-binding cassette protein

Yong-Gui, Gao1,2,3

1School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive,Singapore 6375512NTU Institute of Structural Biology, Nanyang Technological University, 59 Nanyang Drive,Singapore 639798

3Institute of Molecular and Cell Biology, A*STAR (Agency for Science, Technology andResearch), 61 Biopolis Drive, Singapore 138673

The ribosome is one of the richest targets for over half of clinically used antibiotics. We

have determined several structures of ribosome complexes that offers insight into action

mechanism of antibiotic as well as rationalizes mutations resulting in resistance 1,2. On the

other hand, antibiotic could help us trap ribosome in certain state so that the structure can

be reconstructed and visualized 3–5.

Current antibiotic resistance crisis urgently requires understanding of drug resistance

mechanisms and effectively targeted drug discovery. A wide range of mechanisms could

mediate antibiotic resistance, which is currently one of the biggest threats to global health

and food security. Recently, we identified a few ATP-binding cassette family proteins that

can confer resistance across species to various antibiotic classes through unknown

mechanisms 6. In this talk, I will be presenting our recent progress towards a better

understanding of action mechanisms of antibiotic and drug resistance involving ribosome

protection. Elucidating these mechanisms will enable us to rational design improved

antimicrobial agents that overcome multidrug-resistant bacteria.

Reference:

1. Gao, Y. G. et al. The structure of the ribosome with elongation factor G trapped in theposttranslocational state. Science 326, 694-699 (2009).

2. Schmeing, T. M. et al. The crystal structure of the ribosome bound to EF-Tu andaminoacyl-tRNA. Science 326, 688-694 (2009).

3. Kumar, V. et al. Structure of BipA in GTP form bound to the ratcheted ribosome. ProcNatl Acad Sci U S A 112, 10944-10949 (2015).

4. Ero, R., Kumar, V., Chen, Y. & Gao, Y. G. Similarity and diversity of translationalGTPase factors EF-G, EF4, and BipA: From structure to function. RNA Biol 13, 1258-1273 (2016).

5. Kumar, V. et al. Structure of the GTP Form of Elongation Factor 4 (EF4) Bound to theRibosome. J Biol Chem 291, 12943-12950 (2016).

6. Su, W. et al. Ribosome protection by antibiotic resistance ATP-binding cassette protein.Proc Natl Acad Sci U S A 115, 5157-5162 (2018).

Targeting branched chain amino acid biosynthesis forherbicides and antifungalsGuddat, Luke1; Garcia, Mario1, Lonhienne, T1

1School of Chemistry and Molecular Biosciences, The University of Queensland.

Acetohydroxyacid synthase AHAS) is the first enzyme in the branched chain amino acidbiosynthesis pathway. This pathway is present only in plants, bacteria and fungi making it

an excellent target for drug and herbicidediscovery. In total, 50 commercial herbicideshave been developed that target thisenzyme and are now in world-wide use forcrop protection. We have used X-raycrystallography and kinetic studies to showprecisely the mode of action of theseherbicides[1, 2]. Intriguingly, they act by aprocess of slow accumulative inhibitionresulting in the modification of the enzymes’cofactors ThDP and FAD and accelerate aside reaction leading to the production ofperacetate [3]. We have also shown thatAHAS inhibitors are powerful inhibitors ofCandida albicans AHAS (Ki ~800 pM). Incell culture they have MIC values as low as0.03 ug/mL whilst in mice infected withCandida albicans have the ability tocompletely clear infection from the lungs [4].References [1] Lonhienne, T., et al.,Commercial herbicides can trigger theoxidative inactivation of acetohydroxyacidsynthase. Angew Chem Int Ed Engl, 2016.

55(13): p. 4247-4251. [2] Garcia, M.D., et al., Comprehensive understanding ofacetohydroxyacid synthase inhibition by different herbicide families. Proc Natl Acad Sci U SA, 2017. 114(7): p. E1091-E1100. [3] Lonhienne, T., et al., Structural insights into themechanism of inhibition of AHAS by herbicides. Proc Natl Acad Sci USA, 2018. 115E1945-E1954 [4] Garcia, M., et al., Commercial AHAS inhibiting herbicides arepromisingdrug leads for the treatment of human fungal pathogenic infections. Proc. Natl.Acad. Sci. USA, (Accepted).

Crystal structure of AHAS in complexwith penoxsulam one of the world’sleading rice herbicides.

Twisting tales and pKa pathways in key biosynthetic enzymesParker, Emily J1; Bloggs, Joe2

1Maurice Wilkins Centre, Ferrier Research Institute, Victoria University of Wellington,Wellington, New Zealand

Protein conformational changes and dynamics play critical roles in delivering complexenzyme function. We have examined the roles of conformational adjustments in deliveringboth catalysis and allosteric functionality to enzymes that play key roles in amino acidbiosynthesis.

Our studies examine both the active site chemistry and allosteric regulation of ATPphosphoribosyltransferase and 3-deoxy-D-arabino heptulosonate 7-phosphate synthase.Both these enzyme are critical for bacterial function and have been identified as targets forantimicrobial drug design. We have examined both catalytic and allosteric mechanismsusing a range of computational, kinetic and structural techniques. Our studies give insightinto single transduction, complex formation and conformational landscapes for theseproteins.

1. Cross PJ, Allison TM, Dobson RCJ, Jameson GB, Parker EJ. Engineering allostericcontrol to an unregulated enzyme by transfer of a regulatory domain. Proc. Natl. Acad.Sci. U.S.A. 2013, 110, 2111-2116.

2. Lang EJ, Heyes LC, Jameson GB, Parker EJ. Calculated pKa variations exposedynamic allosteric communication networks. J. Am. Chem. Soc. 2016, 138, 2036-45.

3. Nazmi AR, Lang EJM, Bai Y, Allison TM, Othman MH, Panjikar S, Arcus VL, Parker EJ.Interdomain Conformational Changes Provide Allosteric Regulation En Route ToChorismate. J. Biol. Chem. 2016, 291, 21836-21847.

4. Mittelstädt G, Moggré G-J, Panjikar S, Nazmi AR, Parker EJ. Campylobacter jejuniadenosine triphosphate phosphoribosyltransferase is an active hexamer which isallosterically controlled by the twisting of a regulatory tail. Protein Sci. 2016, 25, 1492-1506.

5. Fan Y, Cross PJ, Jameson GB & Parker EJ. Exploring modular allostery viainterchangeable regulatory domains. Proc. Natl. Acad. Sci U.S.A. 2018, 115, 3006-11.

Structural basis for the function of ScpC, a virulence protease from Streptococcus pyogenes

Sivaraman J1, Chong TY1, Prabhakar MT1, Nayak D1, Biswas D2, Pannu NS3, Hanski E4, Jobichen C1 1Biological Sciences, National University of Singapore, Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore. 2Microbiology, National University of Singapore, NUS-HUJ Program on Cellular and Molecular Mechanisms of Inflammation CREATE, U-Town, Singapore, UTown, Singapore, 117543, Singapore. 3Biophysical Structural Chemistry, Gorlaeus Laboratories, Leiden University, Netherlands, Leiden University, Leiden, Netherlands. 4Department of Microbiology and Molecular Genetics Hebrew University Jerusalem, Faculty of Medicine, The Hebrew University of Jerusalem, Israel, Jerusalem, Israel. Group A Streptococcus (GAS; Streptococcus pyogenes) causes a wide range of infections, including pharyngitis, impetigo and necrotizing fasciitis, and results in over half a million deaths annually. GAS ScpC (SpyCEP), a 180-kDa surface-exposed, subtilisin-like serine protease, that act as an essential virulence factor that helps S. pyogenes evade the innate immune response by cleaving and inactivating C-X-C chemokines. ScpC is thus a key candidate for the development of a vaccine against GAS and other pathogenic streptococcal species. We have determined the crystal structures of full-length ScpC wild-type, the inactive mutant, and the ScpC-AEBSF inhibitor complex. We show ScpC to be a multi-domain, modular protein consisting of nine structural domains, of which the first five constitute the PR+A region required for catalytic activity. The four unique C-terminal domains of this protein are similar to collagen-binding and pilin proteins, suggesting an additional role for ScpC as an adhesin that might mediate the attachment of S. pyogenes to various host tissues. The Cat domain of ScpC is similar to subtilisin-like proteases with significant difference to dictate its specificity toward C-X-C chemokines. We further show that ScpC does not undergo structural rearrangement upon maturation through various mutations and subsequent structural study. In the ScpC-inhibitor complex, the bound inhibitor breaks the hydrogen bond between active-site residues, which is essential for catalysis. Collectively, our results demonstrate the structure, maturation process, inhibition and substrate recognition of GAS ScpC, and reveals the presence of functional domains at the C-terminal region.

Figure 1: A) Structure of ScpC, various domains are colour coded and numbered. B) Topology diagram of ScpC. C) The domain organization of ScpC. All the nine domains are numbered and the sequence boundaries are indicated. D) The structure of nine individual domains of ScpC. Colour coded as in the Figure A.

MS#11

MOFs and hybrid materials

Alkylamine Coordination Polymers for CO2 CaptureBatten, Stuart R.1; Turner, David R.1; Chahine, Ali1; Hawes, Chris S.1; Hicks, Jamie1;Emerson, Adrian J.1; Beeching, Lianna J.1

1School of Chemistry, 19 Rainforest Walk, Monash University 3800, Australia

We have been investigating the use of alkylamine ligands in the synthesis of porouscoordination polymers [1]. The amine groups form part of the ligand backbones, and aredesigned to improve the selectivity of carbon dioxide capture over other gases. More than50 new ligands have been made, and more than a dozen porous frameworks identified andtested. The ligands investigated fall into three different categories: (i) azamacrocycles, (ii)piperazines, and (iii) linear alkyl amines. Good carbon dioxide capacities and selectivitieshave been observed, as well as high stability to moisture, unusual structuraltransformations and interesting structural features. Related work has also looked at the useof these materials for the separation of complex aromatic hydrocarbon mixtures, and theincorporation of metal carbonyl species into the ligand backbones, with a view to creatingnew heterogeneous catalysts.

Figure.1. A porous alkylamine coordination polymer.

Reference

[1] Emerson, A.J.; Chahine, A.; Batten S.R. and Turner, D.R. (2018) Coord. Chem. Rev.,365:1-22.

Crystal engineering of chiral coordination polymers with aminoacid derived ligandsCao, Winnie1; Turner, David1

1School of Chemistry, Monash University, Australia;

wei.cao2@monash.edu, david.turner@monash.edu

Chiral coordination polymers have recently been explored as potential stationary phases forenantioselective separations.1 An advantage of porous chiral coordination polymers overother stationary phases is the tunability of the shapes and sizes of the pores.1 Previouswork by our group has shown that porous chiral coordination polymers made using thenaphthalene diimide (NDI) ligand series show promise as materials for chiral resolution.2

In this work, ligands with a smaller aromatic core have been synthesised and incorporatedinto coordination polymers, to both investigate the effect of reducing the size of thearomatic core, and to attempt to reduce the amount of π stacking present, as this reducespore sizes. Coordination polymers containing the achiral ligand GlyPmDI and the chiralligand AlaPmDI have been synthesised with various metallic nodes. Coordination polymerswith the less sterically hindered GlyPmDI ligand are close packed and non-porous due to πstacking. Coordination polymers containing AlaPmDI do not contain π stacking and containpotential pore space. Analyses are currently underway to test the separation properties ofthese coordination polymers.

Figure.1. Synthesis of chiral coordination polymer from chiral bis-amino acid

1. Turner, D. R., Chirality in Network Solids. In Chirality in Supramolecular Assemblies:Causes and Consequences, Keene, R. F., Ed. 2016.

2. Boer, S. A.; Nolvachai, Y.; Kulsing, C.; McCormick, L. J.; Hawes, C. S.; Marriott, P.J.; Turner, D. R., Liquid‐Phase Enantioselective Chromatographic Resolution UsingInterpenetrated, Homochiral Framework Materials. Chem. Eur. J. 2014, 20 (36), 11308-11312.

Pillar[5]arene as a new member in MOFs and hybrid materialsLee, Shim Sung; Lee, Eunji; Kim, Seulgi; Ju, Huiyeong

Gyeongsang National University, Jinju 52828, South Korea

Pillar[n]arenes are new macrocyclic host and their organic guest-based supramolecularchemistry has been extensively studied.[1] However, their coordination compounds are veryrare due to large cavity and lack of metallation site. We introduce bicyclic pillararenes[2] andarmed pillararenes as new members in MOFs and hybrid materials.

Chiral inversion has been a challenging task because chirality controls structures andfunctions of nanostructures and DNA. We synthesized pillar[5]thiacrown (rac-L) andresolved its enantiomers (in-pS-L and in-pR-L). The in-pS-L recognizes Hg2+ to trigger thechiral inversion to out-pR-L, and it takes place in the presence of ClO4

- or NO3-. The

crystallographic approach reveals that the anions act as coordination mode-directingspecies which play a decisive role on the chiral inversion (Figure 1a).[3]

Reaction of the armed pillar[5]arene (L, Figure 1b) with silver(I) in the presence of C8[CN(CH2)nCN, n=8], afforded a 2-D poly-pseudo-rotaxane where C8 not only threads into Lbut also crosslinks parallel arrays. 2-D poly-pseudo-rotaxane is formed by adaptiverearragement of the backbone to minimize the repulsion.

Figure.1

References

[1] Ogoshi, T.; Kanai, S.; Fujinami, S.; Yamagishi, T.-a.; Nakamoto, Y. J. Am. Chem. Soc.

2008, 130, 5022.

[2] Lee, E.; Ju, H.; Kuwahara, S.; Ikeda, M.; Habata, Y.; Lee, S. S. J. Am. Chem. Soc.

2018, 140, 9669.

[3] Park, S.; Lee, S. Y.; Park, K.-M.; Lee, S. S. Acc. Chem. Res. 2012, 45, 391.

Determination of the Absolute Configuration of CompoundsBearing Chiral Quaternary Carbon Centers Using theCrystalline Sponge Method(1)

Shiho, Sairenji1,2,3; Makoto, Fujita1,2

1Institution1Graduate School of Engineering, The University of Tokyo, 2ACCEL, JST,3Organic Materials Group, National Institute for Materials Science (NIMS, as JSPS fellowship)

Chiral quaternary carbon centers are important structural elements that arefrequently found in biologically active natural compounds. The construction of chiralquaternary carbon centers by asymmetric synthesis is therefore a subject of intenseresearch in current synthetic chemistry. Although many excellent methods haverecently been developed for the chiral construction of quaternary carbons, thedifficulty in determining the absolute configuration of these quaternary carbons in theproducts of interest remains a hurdle that is yet to be overcome. Crystalline spongemethod can determine the absolute configuration of chiral compounds by the X-rayBijvoet method without introducing heavy atoms into the substrate because heavyatoms are already present in the host sponge framework (Zn and I). Here, themethod is applied to the absolute configuration determination of chiral compoundswith quaternary carbons, which were prepared by organo- catalytic cyclizationreactions developed by Sasai and Ooi groups. Several organic compounds bearingquaternary carbons were included in the single crystals of the crystalline spongecomposed of ZnI2 and a tridentate panel ligand. X-ray analysis of the inclusioncrystals clearly afforded structures of the incorporated compounds including theirabsolute configurations even though they have no heavy elements (Fig 1).

Figure.1. Crystal structure of compounds bearing tetrasubstituted carbons.

(1) S. Sairenji, T. Kikuchi, M. A. Abozeid, S. Takizawa, H. Saisai, Y. Ando, K.Ohmatsu, T. Ooi, M. Fujita Chem. Sci, 2017, 8, 5132-5136.

Metal-organic frameworks with chelating multiamine ligands:synthesis and propertiesWei-Yin Sun

State Key Laboratory of Coordination Chemistry, School of Chemistry and ChemicalEngineering, Nanjing National Laboratory of Microstructures, Collaborative InnovationCenter of Advanced Microstructures, Nanjing University, Nanjing 210023, China

Metal-organic frameworks (MOFs) have attracted great attention due to their diversestructures, interesting properties and potential applications. However, it is still difficult topredict and control the structure and property of MOFs at present since there are variedinfluencing factors such as metal centers, the nature of organic ligands, reaction conditions.In this work, we designed and prepared three new tripodal ligands with chelatingmultiamine sites: 2-((bis(2-aminoethyl)amino)methyl)phenol (HL1), N1-(4-(1H-imidazol-1-yl)benzyl)-N1-(2-aminoethyl)ethane-1,2-diamine (L2) and N1-(4-(1H-1,2,4-triazole-1-yl)benzyl)-N1-(2-aminoethyl)ethane-1,2-diamine (L3), and new MOFs were synthesized byreactions of these ligands with transition metal salts of Zn(II), Cd(II), Cu(II) etc. Forexample, [Zn2(L3)(2,6-NDC)2(H2O)]·1.5DMF·2H2O (1) and [Cd2(L3)(2,6-NDC)2]·1.5DMF·2H2O (2) (2,6-H2NDC = 2,6-naphthalenedicarboxylic acid, DMF = N,N-dimethylformamide) were achieved under solvothermal conditions. Both 1 and 2 haveporous 3D framework structures with void ratio of 27.6% and 26.8%, respectively.Interestingly, 1 and 2 exhibit selective adsorption of methyl orange dye molecule in

aqueous solution and significant CO2/CH4

selectivity at 273 K under atmosphericpressure. In addtion, the activated frameworkof 1 contains 1D tubular channels decoratedwith multi-active sites: NH2-groups andcoordination unsaturated metal sites. Thesestructural features enhance its CO2 adsorptioncapacity and heterogeneous catalytic activityfor the conversion of CO2 to cyclic carbonates.

Figure.1. MOFs 1 and 2 for selectivitiveadsorption and chemical conversion ofcarbon dioxide

Pore Programming in Multicomponent Metal-OrganicFrameworksTelfer, Shane

1 MacDiarmid Institute of Advanced Materials and Nanotechnology, Institute ofFundamental Sciences, Massey University, Palmerston North, New Zealand

Synthetic materials are generally very simple, comprising a limited number of constituents.In contrast, complexity is a hallmark of biological materials, which translates into exquisitefunctional behaviour. This provides the inspiration for constructing synthetic materials usinga plurality of components. In my talk I will outline how this can be accomplished inmulticomponent metal-organic frameworks (MMOFs), a class of porous materials. Weoverturned conventional wisdom in the field to show that the design and synthesis ofMMOFs with three distinct organic components is possible and that they have remarkableproperties. I will focus on catalysis, and will show how the spatial microenvironment aroundan active site can be tuned by installing functional groups on the surrounding linkers.Systematic engineering of the pore structure in this way, so-called pore programming,impacts on the catalytic properties.

Figure.1. Catalytic pocket in a multicomponent metal-organic framework

MS#12

Advanced methods in crystallography,

electron diffraction and cryo-EM

New Phenix tools for validation of cryo-EM maps and modelsPavel V. Afonine1,2

1 Molecular Biophysics & Integrated Bioimaging Division, LBNL, Berkeley, CA, USA2 Department of Physics, Shanghai University, People’s Republic of China

Recent advances in electron cryo-microscopy field resulted in exploding amount of three-dimensional reconstructions and fitted atomic models of bio-macromolecules deposited intoPDB and EMDB, yet tools and methods to perform comprehensive validation of suchmodels are significantly lagging behind. This prompted to conduct an assessment of qualityof all cryo-EM derived atomic models and corresponding reconstructions that are availableso far in both data banks. The goal of this work was three-fold. Firstly, we wanted to identifywhat is lacking in the arsenal of validation methods, and to begin filling the gaps bydeveloping new methods. Secondly, we wanted to exercise existing or newly added toolsby applying them to all available data in order to assess their utility and robustness. Finally,we wanted to obtain an overall assessment of data, model and model-to-data fit quality ofcurrently available cryo-EM depositions in PDB and EMDB. Similar work has been done forcrystallographic entries in the past (for example, Afonine et al (2010). J. Appl. Cryst. 43,669-676), but not yet for cryo-EM (at least to this extent). We find that only about 2% ofatomic models do not possess severe geometric (stereochemistry) violations and only lessthan about a half of models has the correlation with the corresponding experimental mapgreater than 50%, which we find striking. Furthermore, in many cases the re-evaluated mapresolution significantly deviates from reported values; this prompted development of newmethods to assess the resolution. Overall, this work resulted in a new suite of toolsspecifically designed to validate three-dimensional reconstructions and correspondingatomic models that are now available in Phenix software (Afonine et al., 2018,https://doi.org/10.1101/279844). Also, systematic analysis of all data spurred significanteffort to improve atomic model building, refinement and map enhancement (sharpening)software that is tailored specifically to cryo-EM. Details will be presented and discussed.

IPCAS: A Pipeline from Phasing to Model Building andRefinement for X-ray Diffraction Data and Cryo-EM Density MapDing, Wei1; Zhang, Tao1; He, Yao1; Wang, Jiawei2; Wu, Lijie3; Han, Pu1; Zheng, Chaode1;Gu, Yuanxin1; Zeng, Lingxiao4; Hao, Quan4; Fan, Haifu1

1CAS Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy ofSciences, Beijing, 100190, People's Republic of China2School of Life Sciences, Tsinghua University, Beijing, 100084, People's Republic of China3iHuman Institute, ShanghaiTech University, Shanghai, 200031, People's Republic of China4School of Biomedical Sciences, University of Hong Kong, Hong Kong SAR, People'sRepublic of China

A new version of the structure solving pipeline IPCAS (Iterative Protein Crystal-structureAutomatic Solution) has been released, in which the program OASIS [1, 2] performs thedirect-method SAD/SIR phasing and direct-method aided partial-structure extension.OASIS is now capable of dealing with diffraction data at resolution down to 6.9Å. IPCASalso incorporates the widely-used packages CCP4 [3] and PHENIX [4] for locating heavyatoms, density modification, molecular replacement, model building and refinement. Threeimportant modifications to the previous version of IPCAS are the resolution scanningmethod for NCS searching, the alternative model building method for escaping localminima and the extension from using only X-ray data to utilizing also cryo-EM maps. Inaddition, a new graphical user’s interface (GUI) is provided for controlling and real-timemonitoring the whole dual-space iterative process. Applications of the new IPCAS ondifficult cases have yielded promising results, including "direct-method phasing andfragment extension" from low anomalous scattering signal data (paper in preparation), "MRbased partial-structure extension" from low homology model [5] and "initial model building"from low resolution (6.9A) EM map [6].

1. Hao, Q., et al., OASIS: a computer program for breaking phase ambiguity in one-wavelengthanomalous scattering or single isomorphous substitution (replacement) data. Journal of AppliedCrystallography, 2000. 33(3): p. 980–981.

2. Fan, H., et al., Applications of direct methods in protein crystallography for dealing with diffraction datadown to 5 Å resolution. Acta Crystallographica Section A Foundations of Crystallography, 2014. 70(3):p. 239-247.

3. Winn, M.D., et al., Overview of the CCP4 suite and current developments. Acta Crystallogr D BiolCrystallogr, 2011. 67(Pt 4): p. 235-42.

4. Adams, P.D., et al., PHENIX: a comprehensive Python-based system for macromolecular structuresolution. Acta Crystallogr D Biol Crystallogr, 2010. 66(Pt 2): p. 213-21.

5. Zhang, W., et al., Protein-complex structure completion using IPCAS (Iterative Protein Crystalstructure Automatic Solution). Acta Crystallographica, 2015. 71(7): p. 1487-1492.

6. Zeng, L., W. Ding, and Q. Hao, Using cryo-electron microscopy maps for X-ray structuredetermination. Iucrj, 2018. 5(Pt 4): p. 382-389.

Algorithms for real-time unsupervised cryo-EM structure determination Hans Elmlund Monash University Cryogenic electron microscopy (cryo-EM) and single-particle analysis now enables the determination of high-resolution structures of macromolecular assemblies that have resisted X-ray crystallography and other approaches. We developed the SIMPLE program package for cryo-EM image processing, featuring algorithms for all aspects of single-particle image analysis. A recent focus of the SIMPLE development team has been the establishment of a streaming pipeline, allowing real-time image processing of data directly from the microscope with a minimal computer setup. I will describe our SIMPLE-stream package and how it can be used to inform sample selection and data acquisition. In single-particle analysis, large computational requirements limit throughput and rapid testing of new image processing tools. A core focus of my team is therefore development of more efficient image processing algorithms. I will introduce a 3D orientation refinement method based on iterative estimation of per-particle orientation distributions with stochastic hill climbing that achieves near-atomic resolution single-particle 3D reconstruction. I will describe how we obtained an overall speedup of the approach of nearly two orders of magnitude, using mathematical techniques for accelerating the convergence rate. Our accelerated 3D refinement method now enables single-particle image processing on standard over-the-counter desktop computers. Finally, if time permits, I will describe how we have used the SIMPLE algorithms to obtain atomic-resolution 3D reconstructions of metallic nanoparticles imaged embedded in a graphene liquid cell, while tumbling around in solution.

MicroED: conception, practice and future opportunities

Gonen, Tamir1

1Howard Hughes Medical Institute, University of California, Los Angeles, Los Angeles CA90095 USA2Departments of Biological Chemistry and Physiology, David Geffen School of Medicine,University of California, Los Angeles, Los Angeles CA 90095 USA

My laboratory studies the structures of membrane proteins that are important in maintaininghomeostasis in the brain. Understanding structure (and hence function) requires scientiststo build an atomic resolution map of every atom in the protein of interest, that is, an atomicstructural model of the protein of interest captured in various functional states. In 2013 weunveiled the method MicroED, electron diffraction of microscopic crystals, anddemonstrated that it is feasible to determine high-resolution protein structures by electroncrystallography of three-dimensional crystals in an electron cryo-microscope (CryoEM). TheCryoEM is used in diffraction mode for structural analysis of proteins of interest usingvanishingly small crystals. The crystals are often a billion times smaller in volume than whatis normally used for other structural biology methods like x-ray crystallography. In thisseminar I will describe the basics of this method, from concept to data collection, analysisand structure determination, and illustrate how samples that were previously unattainablecan now be studied by MicroED. I will conclude by highlighting how this new method ishelping us understand major brain diseases like Parkinson’s disease; helping us discoverand design new drugs; shedding new light on chemical synthesis; and showing usunprecedented level of details with sub atomic resolutions.

Multi-dimensional liquid phase TEM for studying colloidalnanoparticlesPark, Jungwon1, 2;Kim, Byung Hyo1, 2; Heo, Junyoung1, 2; Kim, Sungin1, 2; Lee, Donghoon1, 2

1School of Chemical and Biological Engineering, Institute of Chemical Processes, SeoulNational University, Seoul, South Korea2Institute for Basic Science (IBS), Nanoparticle Research Center, Seoul 08826, SouthKorea

Liquid cell TEM (LTEM) has been introduced recently for in-situ study of chemical reactionsoccurring in liquid. Liquid cells allow an opportunity to utilize high spatial and temporalresolution of TEM in studying reactions of colloidal nanoparticles. Achieving sub-nm spatialresolution by adjusting the thicknesses of window materials and the encapsulated liquid,important steps in growth trajectories of different types of nanoparticles have been directlyobserved at high-resolution of TEM. Along with computational analysis, we also studygrowth trajectories of ensemble number of nanoparticles. We also observe the diffractionpatterns from individual nanoparticles as they rotate in the liquid cell, and ultimately, we areable to align and invert those images to obtain the 3D atomic structure of individualparticles freely moving in liquid. Obtained 3D density maps unveil structural features ofnanoparticles that have been either underestimated or unattainable in conventionalanalysis. We present our efforts to augment a combination of above-mentioned analyticaltools in directly observing chemical reactions of nanoparticles in reactive environments.

Atomistic and Real-time Structural Characterization in

Metal OxidesJianbo, Wang1; He, Zheng1; Fan, Cao1; Lei, Li1; Lulu, Zhao1; Shuangfeng, Jia1

1School of Physics and Technology, Center for Electron Microscopy, MOE Key Laboratoryof Artificial Micro- and Nano-structures, and Institute for Advanced Studies, WuhanUniversity, Wuhan 430072, China

Metal oxides have been the subject of rapidly growing research motivated by their diversetechnological applications due to the extraordinary physical and chemical properties. Here,employing the simple heating and CVD methods, we show the successful synthesis ofseveral typical metal oxides (such as CuO, ZnO, Al2O3, etc) nanostructures. Furtherstructural investigations indicate that the microstructures can be effectively tuned bycontrolling the growth conditions. Interestingly, the CuO nannosheets show novel twinning(bi-crystal) structures with zigzag twin boundaries (TBs) that were never reported before.With the joint efforts of Cs-corrected transmission electron microscopy and first principlecalculations, the atomic-scale structural features especially the peroidic arrangement ofpoint defects (Cu and O vacancies and interstitials) at the TBs are directly revealed anddiscussed in detail (Fig. 1). In addition, in-situ transmission electron microscopy has beenemployed to study the real-time structural evolution of nanomaterials subjected to externalstimuli, such as mechanical stress and electric field. For example, real-time microstructuralevolution during the sodiation of CuO NWs is recorded applying the electric field. Theseresults provide the intuitive understanding of the atomistic structural information as well asthe structure-property relationship in low-dimensional metal-oxides and will bring both novelopportunities and fresh challenges for the related applications.

Figure.1. Periodic arrangement of point defects at the TBs in CuO.

MS#13

Hot structures-biology

Studies of the trimeric disulfide isomerase PmScsC and itsredox partner PmScsBαFurlong, Emily1,2; Kurth, Fabian1; Choudhury, Hassanul1; Premkumar, Lakshmanane1; Duff,Anthony3; Whitten, Andrew3; Martin, Jennifer1,2

1Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland,4072, Australia2Griffith Institute for Drug Discovery, Griffith University, Nathan, Queensland, 4111, Australia

3Australian Nuclear Science and Technology Organisation, Lucas Heights, New SouthWales, 2234, Australia

Bacterial disulfide isomerases are typically dimeric, thioredoxin-fold proteins whosedisulfide shuffling activity is essential for the correct folding of many proteins. Throughoutthe isomerisation process, the catalytic cysteines can become oxidised, inactivating theisomerase and so they rely on a redox partner protein to reduce them back to their activestate. Proteus mirabilis Suppressor of copper sensitivity protein C (PmScsC) is a disulfideisomerase that surprisingly, functions as a trimer. We have solved the crystal structure ofPmScsC in three different conformations, suggesting that this isomerase has a large rangeof motion. We have also shown that the periplasmic N-terminal domain of the membraneprotein PmScsB (PmScsBα) is the redox partner of this highly dynamic disulfide isomerase.We solved the high-resolution crystal structure of PmScsBα revealing that it comprises twostructurally similar immunoglobulin-like folds and modeled the PmScsC-PmScsBα complexusing data obtained from small angle neutron scattering (SANS) with contrast matching(Figure 1). These findings add to our understanding of the poorly characterised Scsproteins and the process of disulfide bond isomerisation in bacterial pathogens.

Figure 1. SANS model of the PmScsC-PmScsBα interaction.

Structural basis of NAD+ cleavage activity by mammalian andplant TIR domainsHorsefield, Shane1; Burdett, Hayden1; Zhang, Xiaoxiao2; Shi, Yun3; Manik, Mohammad K.1,Gu, Weixi1; Chen, Jian2; Ve, Thomas1,3; Dodds, Peter N.2; Kobe, Bostjan1

1School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience andAustralian Infectious Diseases Research Centre, University of Queensland, Brisbane, QLD4072, Australia2Agriculture and Food, Commonwealth Scientific and Industrial Research Organisation,Canberra, ACT 2601, Australia3Institute for Glycomics, Griffith University, Southport, QLD 4222, Australia

TIR (Toll/interleukin-1 receptor, resistance protein) domains are key components of innateimmunity and cell-death signaling pathways in animals and plants. Signaling depends onself-association and homotypic association of TIR domains. We have recently reconstitutedlarge assemblies of the TLR (Toll-like receptor) adaptor TIR domains and determined thestructure of the filamentous assembly of TLR adaptor MAL by cryo-electron microscopy. Asan unexpected twist, we found that the TIR domains involved in cell-death pathways,including those from the human TLR adaptor SARM1, involved in axon degeneration, andthose from plant immune receptors (NLRs), possess self-association-dependent NAD+-cleavage activity. Crystal structures of human SARM TIR domain and grapevine NLR Run1TIR domain in complex with small-molecule ligands shed light on the structural basis of thisenzymatic activity. Our studies unify the mechanism of function of TIR domains as"signaling by cooperative assembly formation (SCAF)" with prion-like features that leads tothe activation of effector enzymes, and show that some TIR domains can themselvesfunction as effector enzymes. The structures will be useful for therapeutic developmentagainst neurodegenerative and inflammatory diseases and for development of improvedresistance in agricultural crops.

Figure.1. Crystal packing of SARM1 TIR domains (red and blue). Glycerol molecule bound in the active site isshown in green.

Crystal structure of METTL16, an RNA m6A writer that is

essential for mouse embryonic development Andrew A. McCarthy1, Mateusz Mendel2, Kuan-Ming Chen2, David Homolka2, Pascal Gos2, Radha Raman Pandey2, and Ramesh S. Pillai2,

1European Molecular Biology Laboratory, Grenoble Outstation, 71 avenue des Martyrs, 38042, France. 2Department of Molecular Biology, Science III, University of Geneva, 30 Quai Ernest-Ansermet, CH-1211 Geneva 4, Switzerland

RNA N6-methyladenosine (m6A) modifications are highly conserved and widely used for gene expression control. While the METTL3/METTL14 heterodimer adds this mark to thousands of single-stranded transcripts, the substrate requirements and exact physiological roles of the second m6A writer METTL16 remains elusive. Here we present the crystal structure of human METTL16 at 2.5 Å resolution. The structure reveals a SAM methyltransferase domain furnished by an additional N-terminal module, which we show is essential for RNA binding (Fig. 1). Together these two domains form a deep, continuous and electropositive groove that is required for RNA binding, as confirmed by mutagenesis and methylation assays. Furthermore, METTL16, when presented with a random pool of RNAs, only selects structured RNAs for methylation that contain a critical adenosine in a bulge region. Lastly, mouse 16-cell embryos (E3.5 blastocyte) lacking Mettl16 display reduced mRNA levels of its methylation target, the SAM synthetase Mat2a. The consequence of this is a massive transcriptome dysregulation in 64-cell blastocysts that are unfit for further development. These results highlight the crucial role of the METTL16 m6A RNA methyltransferase in early development through regulation of SAM availability.

Figure.1. METTL16 core MTase domain (left) and positively charged RNA-binding groove (right). Reference : Mendel et al., Mol. Cell (2018), https://doi.org/10.1016/j.molcel.2018.08.004

Mechanism of allosteric activation of a prokaryotic small Ras-like GTPase by an asymmetric dimer interactionGayathri Pananghat

Indian Institute of Science Education and Research, Pune, India

The soil bacterium Myxococcus xanthus is a model organism for studying gliding motility. Itachieves reversal in direction of movement by switching the leading and lagging poles, inresponse to environmental signals. The small Ras-like GTPase MglA and its activator(GTPase activating protein or GAP) MglB drive this dynamic process, along with the Frzproteins that form the signal-sensing pathway. To understand the molecular basis of polarityreversals, we determined the crystal structure of a complex of MglA and MglB, whichrevealed that the C-terminal helix (Ct-helix) of one of the protomers of MglB dimerinteracted with a site distal to the nucleotide-binding pocket of MglA. Biochemical andmutational analyses demonstrated that the Ct-helix allosterically regulated the GTPase.The GTPase-Ct-helix interaction is reminiscent of the interaction between the N-terminalhelix and the GTPase domain of the GDP-bound eukaryotic Arl3. Furthermore, full lengthMglB bound to MglA in presence of either GTP or GDP, whereas Ct-helix truncated MglBcomplexed only to GTP-bound MglA. The contribution of the C-terminal helix towards bothGAP and GEF (guanosine nucleotide exchange factor) activities and its asymmetricinteraction with MglA are also being investigated using crystallography and otherbiochemical and biophysical characterisation. Our results uncover a key regulatory step forpolarity oscillations in M. xanthus, which functions through an allosteric site of the smallRas-like GTPase fold.

Structure-based mechanism of nucleotide-dependent restriction endonuclease Saikrishnan, Kayarat Division of Biology, Indian Institute of Science Education and Research, Pune, 411008, India Nucleoside triphosphate (NTP)-dependent restriction endonucleases are one of the most prominent bacterial defenses against invading foreign DNA. These enzymes nucleolytically cleave foreign DNA and thus protect the host cell from bacteriophage infection and also control horizontal transfer of DNA, such as antibiotic resistant genes and pathogenicity islands. The nuclease activity of these enzymes is coupled to the hydrolysis of NTP by an inbuilt NTPase. Deciphering the mechanism of how these enzymes work has been hindered by a lack of structural information of them. We have been studying the mechanism of these enzymes by carrying out X-ray crystallographic studies complemented by biochemical and biophysical studies. These studies have provided unprecedented insights into the molecular basis of the NTPases and their coupling to the nuclease. I will present our efforts to determine the structure of these multidomain enzymes and discuss the mechanistic details that have emerged from them.

Figure.1. A model for DNA cleavage by two converging NTP-dependent restriction endonuclease.

Static and dynamic X-ray crystallographic analyses of reactionintermediate states of mammalian F1-ATPase to reveal thephysical power generation mechanismSuzuki, Toshiharu1,2,3, Yamashita Eiki4, Baba, Seiki5, Hirata, Kunio6, Iida, Naoya7,Kumasaka, Takashi6, Hisabori, Toru2, Endo, Toshiya3, Yoshida, Masasuke3, Noji, Hiroyuki1

1Dept of Applied Chem, Graduate School of Eng, The Univ of Tokyo, 2CLS, Inst ofInnovative Res, Tokyo Tech, 3Dept of Mol Bioscience, Kyoto-Sangyo Univ, 4Inst of ProteinRes, Osaka Univ, 5Japan Synchrotron Radiation Res Inst (JASRI), 6SPring8-center, RIKEN,7Dept of Physics, Waseda Univ

Molecular motors are unique proteins because they can generate physical power by achemical catalytic reaction, hydrolysis of ATP. The actuator-like function has attracted manyresearchers, but the detailed mechanism to produce physical power is still obscurebecause of insufficient structural information. F1-ATPase (F1) is an ATPase domain of FoF1-ATP synthase and functions as a rotary molecular motor. The ~50kDa rotor part rotatesrelative to 330kDa stator by ATP-hydrolysis. To reveal the mechanism, we have establishedstatic and dynamic X-ray crystallographic analytical methods for recombinant bovine F1.The static method provided several molecular state structures at up to 1.55 Å resolution,which included eight rotation intermediate snapshots for the release of product phosphate(Pi) or ADP. In the Pi-releasing intermediates, stepwise displacements in Pi-mimickingwaters, arginine finger, and p-loop Lys residue at the catalytic site induced a globalrearrangement of subunits, which led to driving stepwise rotation of the rotor (~20°). Themechanism was further analysed by the dynamic method. Bovine F1 crystals have asurprising property that the rotor can be rotated inside the crystal without collapsing thecrystal. Thereby, the Pi-driven rotation was induced inside crystals and resultingintermediate structures were determined. The analysis provided intermediate structuresanalogous to the static method, suggesting the validity of the two methods. In addition,ADP-releasing intermediate structures unveiled conformational rearrangement in thecatalytic site for ADP-releasing. These results provided the mechanism that elastic energyinside F1 provided by ATP-binding is released by the trigger of Pi-releasing and convertedinto rotation torque.

MS#14

Microcrystalline materials, ceramics and

minerals

Combining X-ray and neutron diffraction and modelling forbetter understanding advanced materialsAvdeev, Max

Australian Nuclear Science and Technology Organisation

Many advanced materials, such as thermoelectrics, phosphors for light emitting diodes,electrodes and solid electrolytes for batteries, etc. are difficult objects for stand-alonecrystal structural analysis based on diffraction techniques due to intrinsic high disorder ofone of the sublattices. Traditional diffraction data analysis based on atom-centric modelswith explicitly declared atomic positions is often unstable or unable to fully capture all thedetails due to correlations between variables. Additional difficulties arise from the limitationsof X-ray diffraction in locating light elements and distinguishing elements with close atomicnumbers (e.g. Mn/Ni/Ci). Combining X-rays with neutrons and traditional diffraction dataanalysis with other approaches, such as Maximum Entropy Method, and atomisticmodelling and theoretical symmetry analysis allows to reveal a more complete picture. I willillustrate the point using recent studies of several such structurally complex solidelectrolytes, insertion electrode materials systems, and phosphor hosts. All of them havebeen studies for decades and yet complementing experiment with theory and modellingrevealed new features which help understand and design or improve properties.

Origin of the high oxide-ion conductivity in the apatite-typelanthanum silicatesKotaro Fujii1, Masatomo Yashima1

1Tokyo Institute of Technology

Apatite-type rare earth silicates are attractive materials with exhaust application such assolid-oxide fuel cells, due to its extremely high oxide-ion conductivity below 600 oC.Interstitial (excess) oxygens have been believed to be responsible for the high conductivityin apatite-type materials. On the contrary, the present study clearly reveals the presence ofSi vacancies □ in La-rich La9.565(Si5.826□0.174)O26 instead of the interstitial oxygens, bysingle-crystal neutron and X-ray diffraction analyses, density measurements and ab initioelectronic calculations. Higher mobility (lower activation energy) of oxide ions along the caxis is a dominant reason for the high oxide-ion conductivity of La9.565(Si5.826□0.174)O26,compared with La9.333Si6O26. The excess La cations yield the overbonded channel oxygens,leading to their highly anisotropic atomic displacements and high oxygen mobility along thec axis. The novel finding of the overbonding effect without interstitial oxygens would opennew window in the design of better ion conductors.

Figure.1. Crystal structures of the apatite-type oxide-ion conductors La9.333Si6O26 and La9.565(Si5.826□0.174)O26

determined from the single-crystal neutron diffraction studies.

Development of plastic/ferroelectric ionic molecular crystalsHarada, Jun

Department of Chemistry, Faculty of Science, Hokkaido University, Japan

Molecular ferroelectric crystals have recently attracted growing interest as potentialalternatives to or complements of ferroelectric perovskite oxides, mainly due to their non-toxicity (lead-free) and solution processability. The control over crystal orientations,however, still represents significant challenges for practical use of molecular ferroelectriccrystals because of their uniaxial ferroelectricity due to low symmetry of the crystalstructures. We have recently found that a class of molecular compounds known as plasticcrystals can be promising targets for the development of new ferroelectric materials.1,2 Theplastic crystal phase is often found in molecular compounds with globular molecularstructures, such as adamantane and tetrachloromethane. In the plastic crystal phase, themolecules undergo rapid isotropic rotator motions and lose their order of orientation, whichresults in highly symmetric crystal structures that usually belong to the cubic crystal system.

We have found that ionic plastic crystals can be ferroelectric crystals in the lowertemperature phases (at and around room temperature), provided that the constituentmolecules are judiciously chosen from globular ionic molecules. Because of the cubiccrystal symmetry of the plastic crystal phase, which is the paraelectric phase, theferroelectric crystals exhibited multiaxial ferroelectricity, which is unique relative toconventional molecular crystals. The plastic/ferroelectric molecular crystals showedferroelectric polarization switching in the form of polycrystalline powder pellets. Free-standing films (thickness ~50 m) can be readily prepared by pressing powdered samplesof these compounds. The obtained films exhibited a relatively large piezoelectric response(d33 values reaching 110 pC N–1) at room temperature.

1 J. Harada, et al., Nature Chem., 2016, 8, 946.2. J. Harada, et al., J. Am. Chem. Soc., 2018, 140, 346.

An algebraic approach to cooperative rotations in networks of interconnected rigid units Campbell, Branton1; Howard, Christopher2; Averett, Tyler1; Whittle, Thomas3; Schmid, Siegbert3; Machlus, Shae1; Yost, Christopher1; Stokes, Harold1

1Department of Physics & Astronomy, Brigham Young University, Provo, Utah, 84602, USA 2School of Engineering, The University of Newcastle, University Drive, Callaghan, NSW, 2308, Australia 3School of Chemistry, The University of Sydney, Sydney, NSW, 2308, Australia

Crystalline solids consisting of three-dimensional networks of interconnected rigid units are ubiquitous amongst functional materials. In many cases, application-critical properties are sensitive to rigid-unit rotations at low-temperature, high pressure, or specific stoichiometry. The shared atoms that connect rigid units impose severe constraints on any rotational degrees of freedom, which must then be cooperative throughout the entire network. Successful efforts to identify cooperative-rotational rigid-unit modes (RUMs) in crystals have employed split-atom harmonic potentials, exhaustive testing of the rotational symmetry modes allowed by group representation theory, and even simple geometric considerations. Here, we present a purely algebraic approach to RUM identification wherein the conditions of connectedness are used to construct a linear system of equations in the rotational symmetry-mode amplitudes.

This new approach has been used to reproduce the established results for octahedral tilting in perovskites, similarly for the displacement and tilting of tetrahedra in quartz, and to obtain complete results for octahedral tilting in the tungsten bronzes. The structure of hexagonal tungsten bronze, along with an indication of one possible tilt pattern, is shown in Fig. 1.

Figure.1. A representation of one layer of the idealised hexagonal tungsten bronze, M1/3WO3, in space group P6/mmm. This shows the WO6 octahedra, the O ions at the corners of these octahedra, and the cations M in the hexagonal tunnels. The arrows are added to indicate the tilt pattern in the lower symmetry structure in P63/mmc; they represent the tilt axes as well as the senses and relative magnitudes of the tilts, The ‘equatorial’ O atoms are marked + or – according as the tilting would set them above or below the z=0 plane. The tilts reverse in sense between one layer and the next.

The many phases of acrylonitrileH.E. Maynard-Casely1, M. Malaska2 and R. Hodyss2

1Australian Nuclear Science and Technology Organisation, Kirrawee DC, New South Wales2232, Australia2Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive,Pasadena, California 91109, U.S.A.

Of the molecules predicted to be formed by Titan photochemistry, acrylonitrile (CH2CHCN,

also known as 2-propenenitrile and vinyl cyanide) has garnered interest of late having

recently been observed in the atmosphere of Titan [1]. Additionally, based on theoretical

modelling, acrylonitrile has been hypothesized to be able to be able to form membrane-like

structures in liquid methane [2], providing potential for non-aqueous biological functions.

However, despite the intense interest that acrylonitrile has received from the planetary

community, it has been rather unexplored by crystallographers and diffraction experiments.

Liquid at room temperature, acrylonitrile freezes at ~190 K with spectroscopy results

suggesting that it undergoes a phase transformation at 160 K [3]. The Cambridge

structural database only contains one entry for pure acrylonitrile (refcode POQMIR), a

disordered orthorhombic phase determined at 153 K from a laboratory single crystal study

[4]. We have recently conducted Raman spectroscopy and neutron diffraction results that

confirm the transition at 160 K, but also show a further phase transformation at 152 K,

indicating that there are three distinct forms of acrylonitrile. We will present this work and

how it alters our understanding of Titan’s surface.

1. Palmer, M.Y., et al. Science Advances, 2017. 3(7): p. e1700022.2. Stevenson, J., J. Lunine, and P. Clancy, Science advances, 2015. 1(1): p.

e1400067.3. Toumi, A., et al.. Icarus, 2016. 270: p. 435-442.4. Yokoyama, Y. and Y. Ohashi, Bulletin of the Chemical Society of Japan, 1998. 71(2):

p. 345-348.

Structural Flexibility and Tunable Functionality White, Tim1; Baikie, Tom1; Fang, Yanan1; Yin, Tingting2; Shen, Ze Xiang2; Ramanujan, Raju1; Wei, Fengxia3; Dintakurti, Sai1; Hanna, John4 1School of Materials Science & Engineering, Nanyang Technological University, Singapore 2School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 3Institute of Materials Science & Engineering, Agency for Science, Technology & Research, Singapore 4Department of Physics, University of Warwick, Coventry, United Kingdom

The tailoring of functional materials is frequently controlled by simultaneously manipulating crystal structure, crystal chemistry and crystal morphology. This axiomatic principle is illustrated through recent studies of apatite and melilite ion conductors, hybrid perovskite photovoltaics and magnetic alloys that combine diffraction, spectroscopy and imaging. In every case, the inherent structural flexibility of the materials is both the source of their functional utility, while also proving challenging to understand and control. Sometimes, such problems can be simplified by in situ high pressure observations that induce functional changes through modification in bond strength and geometry while avoiding the complication of chemical adjustments. For example, in hybrid perovskites changes in power conversion efficiency (PCE) through the application of external pressure provide guidance for chemical tailoring, where tuning ionic sizes effectively modifies ‘internal pressure’ and stabilizes new polymorphs. By chemically adjusting hybrid perovskite compositions near to polymorphic boundaries, the application of modest pressure can be sufficient to initiate phase changes and band gap adjustments.

Figure.1. Pressure-induced MAPbBr6 polymorphs.

MS#15

Database developments,

validation & data mining

Ligand Validation for the Protein Data BankBurley, Stephen K.1,2

1RCSB PDB, Institute for Quantitative Biomedicine, Rutgers, The State University of New Jersey,Piscataway, NJ 08854, United States.

2RCSB PDB, Skaggs School of Pharmacy and Pharmaceutical Sciences and San DiegoSupercomputer Center, University of California San Diego, La Jolla, CA 92093, United States.

The Protein Data Bank (PDB) is the global repository for experimentally-determined 3Dstructures of biological macromolecules. It is managed by the Worldwide Protein DataBank (wwPDB, wwpdb.org). In addition to biopolymer structure data, the PDB ChemicalComponent Dictionary (CCD) catalogues small molecule ligands, encompassing IUPACatom nomenclature for standard amino acids and nucleotides, stereo-chemicalassignments, bond order assignments, experimental model and computed idealcoordinates, systematic names, and chemical descriptors. Precise knowledge ofinteractions between macromolecules and small ligands is central to our understandingof biological function, drug action, mechanisms of drug resistance, and drug-druginteractions.

The wwPDB OneDep system supports PDB data deposition, validation, andbiocuration. OneDep produces Validation Reports using standards developed withexpert task forces. For X-ray structures, the fit of the ligand to electron densitydifference maps is assessed quantitatively using real-space R-factors (RSR and RSRZ-scores). Within OneDep, 3D electron density difference maps are produced for expertreview. For released structures, precomputed electron density difference maps forbound ligands and wwPDB Validation Reports can be accessed from RCSB PDBStructure Summary pages.

The 2015 Ligand Validation Workshop generated community recommendations aimedat further improving validation of ligand structures in the PDB (Adams et al. 2016;Structure 24, 502-508). Progress towards implementation of these recommendationswill be reported together with ongoing enhancements to the CCD and wwPDBValidation Report.

wwPDB members are RCSB PDB (supported by NSF, NIH, and DOE), PDBe (EMBL-EBI, Wellcome Trust,BBSRC, MRC, and EU), and PDBj (NBDC-JST), and BMRB (NIGMS).

What is a dataset?Hester, James R.1

1ANSTO, Locked Bag 2001, Kirrawee DC, Australia 2232

Several widely-accepted standards now exist that make finding and citing datasetsstraightforward. However, after a dataset has been found, application software is notgenerally able to determine how to process the dataset or if the data are appropriate to itstask, especially given that data may be stored in a variety of formats and arrangements anddivided or aggregated. If a dataset is formed from several separate digital objects, there isno standard, computationally-robust way to describe their relationships to a computer.These and other issues are easy enough for a human to program on a case-by-case basis,but a generic framework that would underpin automatic processing is currently lacking.

The contents of any dataset can be modelled as a collection of relational tables [1]. Amachine-readable set of definitions for the columns of these tables, such as those providedby the CIF dictionaries, can provide all of the information necessary for performingcomputations on the dataset. A dataset is complete if the set of columns required to fulfill atask is available or can be computed from the rest of the data. A particular use-case isthus equivalent to a list of columns.

Application software accesses the data via an interface that presents that data in relationalform using a shared standard ontology to name the columns. By requesting specificcolumns, software can immediately determine if the dataset is suitable for its needs.Integration of multiple distinct data blobs is equivalent to filling in blocks within tables.

[1] Hester, J. R. (2016) "A robust, format-agnostic scientific data transfer framework", DataScience Journal 15, p12 DOI:http://doi.org/10.5334/dsj-2016-012

Databases and Web services from PDBj for ElectronMicroscopyKawbata, Takeshi1; Suzuki, Hirofumi1; Kurisu, Genji1

1Institution for Protein Research, Osaka University

Cryo-electron microscopy has recently emerged as a powerful technique to solve atomic3D structure. Protein Data Bank Japan (PDBj) provides several WEB databases andservices for supporting researchers of electron microscopy. The database “EM navigator”provides a user-friendly view of 3D density maps stored in EMDB (Electron MicroscopyData Bank). The “Omokage search” service enables us to search 3D maps or atomicmodels with similar shapes by the query map or model given by a user. The “gmfit” serviceprovides fitting calculations between a 3D map and an atomic model through WEB. Thecalculation is fast due to the density is approximately represented as Gaussian mixturemodel. The gmfit program has improved to perform a partial fitting of an atomic model inonly a subspace of the 3D map, using masking function. The helix detection program usingGaussian function is almost ready to open. Finally, we now announce a mirror site of theEMPIAR database (Electron Microscopy Public Archive) is open in Japan(https://empiar.pdbj.org). EMPIAR is a public resource for 2D electron microscopy imagesdeveloped in EMBL-EBI. A set of 2D images are raw experimental data to reconstruct a 3D

density map, its file size is quite large:average file size is about 500 Gbyte.Although these 2D images are very large tohandle, they are necessary to validate 3Dmap, enhance developments of imageprocessing software, and educate and trainEM users. We are now preparing to open thedeposition site of EMPIAR in PDBj.

Figure.1. Database and services for EM from PDBj

The Cambridge Structural Database – Developments indeposition and accessLightfoot, Matthew P.1; Ward, Suzanna C.1

1The Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK

Over the last few years CCDC have developed services to make it as easy as possible todeposit and access small molecule crystal structure data and this presentation will highlightseveral of these developments. Recent changes to our deposition services allow depositorseasily to deposit, view and manage their data. This talk will detail some of these changesincluding the ability to share data across institutions and developments to ensure thatcrystallographers are recognised for their work. As well as these recent changes we willdiscuss ways in which we are looking to further develop these services.

An important area for CCDC is data quality and integrity and we will explore our validationchecks and new deposition guidelines which aim to aid depositors and help improve thequality and integrity of the data that is deposited at CCDC. We will also discuss theincreasing use of data publications, in particular CSD Communications, as a way to directlyshare data and how we are working to ensure the rise of data publications does notnegatively impact the quality of the CSD.

We will conclude this presentation by highlighting recent efforts to integrate and link withother data resources including our recent collaboration with FIZ Karlsruhe that resulted inthe launch of joint deposition and access services for crystallographic data across allchemistry. We will show how these new services enable researchers to share data througha single deposition portal and provide free worldwide access to all chemical structures.

Figure.1. CCDC/FIZ Karlsruhe joint access service

The element of trust: validating and valuing crystallographicdataMcMahon, Brian1; Helliwell, John R.2; Hester, James R.3

1International Union of Crystallography, 5 Abbey Square, Chester CH1 2HU, UK. E-mail:bm@iucr.org2School of Chemistry, University of Manchester, Manchester M13 9PL, England2Australian Nuclear Science and Technology Organisation, New Illawarra Road, LucasHeights, NSW 2234, Australia

The IUCr encourages best practice in data management, and performs data validation in itsown journals and by collaboration with structural databases. Its Crystallographic InformationFramework (CIF) provides precise data definitions and led to automated criteria (checkCIF)for testing the reasonableness of a derived structural model. These procedures for small-molecule structures are used by many journals and databases. (Reciprocally, PDBvalidation reports are inspected during the review process of IUCr biological journals.) Manyjournals and databases also request structure-factor or other underlying data to allow moredetailed validation. Attention is now shifting from processed to raw experimental data. AnIUCr Working Group explored the idea of routinely depositing raw diffraction images.Storing such large volumes of data was once prohibitively expensive, but technologicalimprovements have overcome this objection. There is ongoing debate about the scientificvalue of image deposition, but workshops and publications have informed the discussionwith detailed analysis of the potential scientific benefits (DDDWG, 2017). Validation of rawdata sets will involve characterisation of image data (using imgCIF-based data names) andformal requirements for essential metadata to allow interpretation of individual images.Work towards such requirements is being carried out under the aegis of the IUCr's Dataand CIF Committees (CommDat and COMCIFS). The recently upgraded CIF specificationfacilitates DDLm, a machine-readable description of relationships between data items thatcan automatically generate software methods for testing and evaluating such relationships.This will go further towards ensuring the integrity of published and depositedcrystallographic data.

Reference

DDDWG (2017). Final report of the Diffraction Data Deposition Working Group.http://forums.iucr.org/viewtopic.php?f=21&t=396

Data for Crystallisation – Answers are in the distanceNewman, Janet1, Fazio, Vincent J2, Khassapov, Alex2, Ristic, Marko1, Rosa, Nicolas1,Thorburn, Luke1

1 CSIRO Biomedical Manufacturing 343 Royal Parade Parkville VIC 3054 Australia

2 CSIRO Scientific Computing Private Bag 10 Clayton South VIC 3169 Australia

Most attempts to crystallise a protein (or any macromolecule) start by setting up the proteinagainst one or more commercially available screens. There are a good number of vendorsof crystallisation screens, and each sells many different screens. Navigating through whatis available, and what each screen contains is challenging, and comparing offeringsbetween vendors is almost impossible as there are no standards for how crystallisationdata should be described. We have created a defined vocabulary for crystallisationexperiments, and have also implemented the concept of ‘distance’ between twocrystallisation conditions. This allows us to build up a database of crystallisation conditionsand screens – and to search on screens, conditions, chemicals or similarity. Thisinformation can be accessed through the website c6.csiro.au. The webtool can be used toguide crystallisation campaigns, both initial searches and optimisation experiments, andsuggestions on how this tool can be used during the course of crystallisation will bepresented.

Figure.1. Visualise Phase Space graph from the C6 webtool.

MS#16

Macromolecular

complexes and

assemblies

Structure and Dynamics of the Core Fe/S Cluster AssemblyComplexCygler, Miroslaw1, Boniecki, Michal1, Freibert, Sven2, Mühlenhoff, Ulrich2, Lill, Roland2

1Department of Biochemistry, University of Saskatchewan, 107 Wiggins Road, Saskatoon,SK S7N 5E5, Canada; 2Institut für Zytobiologie und Zytopathologie, Philipps-Universität,Robert-Koch-Strasse 6, Marburg 35032, Germany.

Iron-sulfur (Fe/S) clusters are essential protein cofactors, which are present in all kingdomsof life. They are crucial for many cellular functions, including DNA maintenance, proteintranslation, and energy conversion. Key components of the Fe/S cluster assemblymachinery, cysteine desulfurase, scaffold protein, ferredoxin and CyaY/frataxin, were highlyconserved during evolution. In eukaryotes, where the de novo Fe/S cluster synthesisoccurs in the mitochondria, two additional components were incorporated into the coremachinery, namely the helper protein ISD11 and acyl carrier protein ACP. Although theISD11 protein was discovered several years ago, its role in the Fe/S assembly process hasnot been elucidated. Similarly, the role of ACP in the Fe/S cluster synthesis was enigmatic.We have determined the crystal structures of three different NFS1-ISD11-ACP complexeswith and without ISCU. These structures suggest a regulatory role in the mitochondria forthe helper protein ISD11 with associated ACP. They also demonstrate a dynamic nature ofthis assembly complex. Using SAXS analyses, we were able to define a three-dimensionalarchitecture of the complete mitochondrial Fe/S cluster biosynthetic complex, includingfrataxin and ferredoxin. Mutational analysis and biochemical studies support this structuralmodel. The current resolution of these structures is in the 1.6-1.8 Å range, allowing detailedanalysis of the interactions between the subunits.

Figure 1. The complex of NFS1-ISD11-ACP-ISCU

A bidentate Polycomb Repressive-Deubiquitinase complex isrequired for efficient activity on nucleosomesFoglizzo, Martina1; Middleton, Adam1; Burgess, Abigail1; Crowther, Jennifer2; Dobson,Renwick2,3; Murphy, James4,5; Day, Catherine1; Mace, Peter1

1Biochemistry Department, School of Biomedical Sciences, University of Otago, Dunedin,New Zealand2Biomolecular Interaction Centre, School of Biological Sciences, University of Canterbury,Christchurch, New Zealand3Bio21 Molecular Science and Biotechnology Institute, Department of Biochemistry andMolecular Biology, University of Melbourne, Melbourne Australia4The Walter and Eliza Hall Institute of Medical Research, Parkville, Australia5Department of Medical Biology, University of Melbourne, Parkville, Australia

Attachment of ubiquitin to lysine 119 of Histone 2A (H2AK119Ub) is an epigenetic markcharacteristic of repressed developmental genes, which is removed by the PolycombRepressive-Deubiquitinase (PR-DUB) complex. Here we report the crystal structure of theDrosophila PR-DUB, revealing that the deubiquitinase Calypso and its activating partnerASX form a 2:2 complex. The bidentate Calypso–ASX complex is generated bydimerisation of two activated Calypso proteins through their coiled-coil regions. Disruptingthe Calypso dimer interface does not affect inherent catalytic activity but inhibits removal ofH2AK119Ub, as a consequence of impaired recruitment to nucleosomes. Mutating theequivalent surface on the human counterpart, BAP1, also compromises activity onnucleosomes. Together, this suggests that high local concentrations drive assembly ofbidentate PR-DUB complexes on chromatin—providing a mechanistic basis for enhancedPR-DUB activity at specific genomic foci, and the impact of distinct classes of PR-DUBmutations in tumorigenesis.

Structure and function of tripartite drug efflux transporters inGram-negative bacteria.Murakami, Satoshi1; Okada, Ui1

1Department of Life Science and Technology, Tokyo Institute of Technology

Multidrug resistance caused by drug efflux transporter is a serious problem in antibiotictreatment of numerous bacterial infections. The envelope of Gram-negative pathogenscontains unique tripartite machineries that export noxious compounds from the cell. Thesemachineries are composed of a plasma membrane transporter and outer membrane porinthat are connected by a periplasmic adaptor protein. AcrB which belong to the Resistance-Nodulation-cell Division (RND) superfamily is one of the most characterized tripartitetransporter complex. ATP-binding cassette (ABC) and major facilitator superfamily (MFS)transporters can also be part of tripartite complexes, and share similar or identicalcomponents with RND transporters. The tripartite-type ABC transporter, MacB in complexwith outer membrane porin, TolC and periplasmic adaptor protein, MacA, is an importantefflux transporter that mediates the extrusion of macrolides, peptide toxins, virulencefactors, siderophores, lipopolysaccharides and protoporphyrins. Recently, we solved thecrystal structure of MacB at 3.4 Å resolution. MacB forms a dimer in which each protomercontains a nucleotide binding domain and four transmembrane helices that protrude in theperiplasm for interaction with the periplasmic adaptor protein, MacA. The MacB structureexhibits significant differences with known structures of ABC transporter proteins, andprovides a framework for further elucidation of the mechanisms of these important tripartiteefflux transporters.

structures of the Herpes simplex virus type 2 B-capsid &C-capsid with capsid-vertex-specific component

Zihe Rao (raozh@tsinghua.edu.cn) (Tsinghua University Beijing, China)

Herpes simplex viruses (HSVs) cause human oral and genital ulcer diseases.Patients with HSV-2 have a higher risk of acquiring a human immunodeficiencyvirus infection. HSV-2 is a member of the α-herpesvirinae subfamily thattogether with the β- and γ-herpesvirinae subfamilies forms the Herpesviridaefamily. Structurally and genetically, human herpesviruses are amongst thelargest and most complex of viruses. Using an optimized reconstructionstrategy, we report the structures of HSV-2 B-capsid at 3.1 Å resolutions and C-capsid at 3.75 Å resolution which includes, 28,138 residues in the asymmetricunit, belonging to 46 different conformers of 4 capsid proteins (VP5, VP23,VP19C, VP26) making up 4 types of capsomers (C-Hex, E-Hex, P-Hex, Pen)and triplexes. Acting as core organizers, VP5s exhibit striking differences inconfiguration and mode of assembly to form extensive intermolecular networks,involving VP26s and triplexes via covalent (25 disulfide bonds per asymmetricunit) and non-covalent interactions, that underpin capsid stability and assembly.Conformational adaptations of these proteins induced by theirmicroenvironments lead to the assembly of a massive quasi-symmetric shell,exemplifying the structural and functional complexity of HSV. We also presentatomic models of multiple conformers for the C-capsid proteins (VP5, VP23,VP19C and VP26) and CVSC. Comparison of the HSV-2 homologues yieldsinformation about structural similarities and differences between the threeherpesviruses sub-families and we identify α-herpesvirus-specific structuralfeatures. The hetero-pentameric CVSC, consisting of a UL17 monomer, a UL25dimer and a UL36 dimer, is bound tightly by a five-helix bundle that formsextensive networks of subunit contacts with surrounding capsid proteins, whichreinforce capsid stability. The portal structures of HSV2 B-capsid and C-capsidalso discussed.

Related publications:Yuan S, et al. Science. 2018 Apr 6;360(6384).

Wang J，et al. Nature Comm. (in press)

Wang N, et al. in preparation.

Structural basis for regulation of histone acetylation

Rui-Ming Xu

National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China

Lysine acetylation is among the first post-translational modifications of histones to be discovered, and it plays prominent roles in chromatin-based regulation of gene expression. Enzymatic acetylation and deacetylation of histones provide major means of modulation of degrees of histone acetylation. Apart from spatiotemporal changes of enzyme abundances, conformational dynamics and protein-protein interaction can significantly influence enzymatic activities of certain histone acetylases and deacetylases. We have studied the structural basis for regulation of deacetylase activities of Sirtuins, as well as the molecular mechanism by which histone chaperone Asf1 stimulates the acetylation of H3K56 by Rtt109. Our results provide mechanistic insights into allosteric regulation of histone acetylation and deacetylation, and this knowledge should benefit the design of small molecule modulators of histone/protein acetylation.

Structural basis of CD96 immune receptor recognition of nectin-like protein-5 (CD155)Watson, Gabrielle1,2; Deuss, Felix1,2; Fu, Zhihui1,2; Rossjohn, Jamie1,2,3; Berry, Richard1,2

1 Infection and Immunity Program and The Department of Biochemistry and MolecularBiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia2 Australian Research Council Centre of Excellence in Advanced Molecular Imaging,Monash University, Clayton, VIC 3800, Australia3 Institute of Infection and Immunity, Cardiff University School of Medicine, Heath Park,Cardiff CF14 4XN, UK

CD96, DNAM-1 and TIGIT constitute a group of immunoglobulin superfamily receptors thatare key regulators of tumor immune-surveillance. Within this axis, CD96 recognises theadhesion molecule nectin-like protein-5 (necl-5), although the molecular basis underpinningthis interaction remains unclear. We show that the first immunoglobulin domain (D1) ofCD96 is sufficient to mediate a robust interaction with necl-5, but not the DNAM-1 andTIGIT ligand, nectin-2. The crystal structure of CD96-D1 bound to the necl-5 ectodomainrevealed that CD96 recognized necl-5 D1 via a conserved ‘lock and key’ interactionobserved across TIGIT-necl complexes. Specific necl-5 recognition was underpinned bytwo novel structural motifs within CD96, namely an ‘ancillary key’ and an atypical ‘lock-lock’linkage. Mutational analysis showed that these specific interactions were critical for necl-5binding, whilst simultaneously providing insights into the unique ligand specificity of CD96.Our findings have implications for the design of novel anti-cancer immunotherapeutics.

MS#17

Hot structures – chemistry

On model phasing for Thorium (and other heavy element)

clusters – getting the hydrides right

Edwards, Alison J.,1; Cheng, Jianhua2 1 Australian Centre for Neutron Scattering, ANSTO, New Illawarra Rd, Lucas Heights,N.S.W. 2 Changchun Institute for Applied Chemistry, Chinese Academy of Sciences, Changchun, China

The rekindling of the Laue method as a data collection strategy for neutron scattering has shifted the boundaries of what can be achieved using neutrons as the probe for chemical crystallographic investigations. Since the inception of the KOALA instrument at ANSTO, it has been observed that the interplay between instrument specifications, crystal size, crystal quality, diffraction pattern resolution and temperature can be manipulated to yield diffraction patterns from which a useful neutron diffraction data set may be extracted, even at relatively low resolution. We control only a subset of these factors.

Critical to the successful determination of many structures, but in particular, the location of hydrides adjacent to heavy elements is the starting model derived from X-ray diffraction. Aspects of an X-ray study which can be published without complete modelling must be revisited when neutron Laue diffraction data are available. The application of SQUEEZE in X-ray structure determinations to give starting phases can render otherwise worthwhile neutron data uninterpretable. Due in part to the limited range of neutron scattering factors, and their nonlinear distribution it is found to be critical to ensure that a complete and correct model must be derived from the X-ray diffraction data if the neutron diffraction analysis is to proceed to an optimal outcome. The need for critical review of the space group in the successful modelling of neutron data in such cases is also observed. A thirteen thorium cluster will be the exemplar.

Figure.1. The Th13 cluster core

Kinetic Assembly of Porous Coordination NetworksKawano, Masaki

Department of Chemistry, School of Science, Tokyo Institute of Technology

Because of the presence of intermolecular interactions during self-assembly, there aremany metastable structures before reaching the thermally most stable structure. Bycontrolling the weak intermolecular interactions, we can trap various metastablecoordination networks which will not be obtained by conventional thermodynamic controllike solvothermal synthesis. In sharp contrast to the thermodynamic synthesis ofcoordination networks, kinetically trapped metastable networks were not paid muchattention, because firstly it is very difficult to analyze crystal structures. Recently we havedemonstrated that it is possible to perform ab initio powder structure determination ofporous coordination networks using low resolution data.1-3 In addition, we elucidated thattotally different coordination networks can be selectively prepared using the same startingmaterials by thermodynamic and kinetic control.4,5 In this talk, we will introduce selectivepreparation of metastable porous networks by kinetic control, the chemistry of porousnetworks, their unique sorption properties, redox properties, and X-ray snapshots ofchemical transformation in a pore.6-8

1 J. Martí-Rujas, M. Kawano, Acc. Chem. Res., 2013, 46, 493.2 Y. Yakiyama, et al Chem. Commun., 2015, 51, 6828.3 H. Ohtsu, M. Kawano, Dalton Trans., 2016, 45, 489.4 H. Ohtsu, et al J. Am. Chem. Soc., 2013, 135, 11449.5 H. Kitagawa, et al Angew. Chem. Int. Ed., 2013, 125, 12621.6 J. Y. Koo, et al J. Am. Chem. Soc., 2016, 138, 1776.

7 H. Kitagawa, et al IUCrJ，2016, 3, 232.

8 H. Ohtsu, M. Kawano, Chem. Commun., 2017, 53, 8818.

Mixed-metal MOFs comprised of phenanthroline ligands with carboxylate functionalities Macreadie, Lauren1 1 CSIRO, Clayton, VIC 3168, Australia.

Deepening interest into metal organic frameworks (MOFs) is seen in wider areas of science and engineering due to the ease of tunability of the MOF system, leading to a myriad of interesting and variable applications. The ability to vary the properties and behaviour of the MOF through judicious choice of single, or multiple, ligand and metal components provides solid scope for creativity and application mediated design for MOFs. Despite the successful development of MOFs with multi-ligand systems, there are few examples of mixed metal MOF systems. Mixed metal MOF systems provide great potential when working towards specific applications, namely catalysis, while also offering some control of MOF formation using crystal engineering strategies.1 A key challenge in the formation of mixed metal MOF systems is control of selective coordination to the ligand, which can often lead to multi-product formation. This can be addressed, however, through use of ligands with both nitrogen and oxygen donor systems and metals with similar Coulombic charge.2

Here is presented research into coordination polymers comprised of 2-(4-Carboxyphenyl)imidazo[4,5- f]-1,10-phenanthroline (HNCP) ligands, which offer both oxygen and nitrogen donor atoms. Through careful choice of reaction conditions and metal components, and often inclusion of bridging co-ligands, we are able to selectively synthesise 1D-, 2D- and 3D-coordination polymers. Interestingly, 2D-coordination polymers were formed through pre-synthesising tritopic ruthenium metallo-HNCP ligand. Combination of this metallo-ligand with transition metal salts led to a porous, stable 2D (6,3) honeycomb shaped net. Single crystal of the coordination polymers were used to facilitate structural elucidation, while powder diffraction techniques allowed phase purity and stability to be determined.

Figure 1. (left) The packing structure of [CoIIL3-RuII](NO3) as viewed down the z axis; (right) space filling diagram showing the tubular 2-D structure of [CoIIL3-RuII](NO3).

1. Sun, D. et al., Inorg. Chem., 2015, 54, 8639−8643. 2. Dhakshinamoorthy, A. et al., Catal. Sci. Technol., 2016, 6, 5238–5261.

Structure determination of twinned and poorly diffractingcrystals suffering radiation damage using the MX beamlines atthe Australian Synchrotron.Rousset, Elodie,1,2 Gable, Robert W.,1 Boskovic, Colette1

1University of Melbourne, School of Chemistry, Parkville Campus, Melbourne, VIC 3010,Australia2University of Reims - Champagne Ardenne, Institut de Chimie Moléculaire de Reims,Campus Sciences Exactes et Naturelles, 51100 Reims, France

Single-molecule magnets (SMMs) are molecular materials that exhibit a slow relaxation ofthe magnetisation. These properties may find applications in information storage devices orquantum computers. However, the present limitation remains in the design of compoundspresenting a large energy barrier to the reversal of the magnetisation, closer to applicabletemperatures.

Trivalent lanthanoid (Ln) ions are found to be good SMM candidates due to their significantintrinsic magnetic anisotropy and large magnetic moment. The energy barrier tomagnetisation reversal for Ln-SMMs arises from the crystal field (CF) splitting of the groundstate and depends on the local symmetry of the LnIII ion. The geometry around the metalcentre is therefore of primary importance. The most straight-forward technique used tocharacterise the atom connectivity and precise geometry continues to be single-crystal X-ray crystallography, which largely relies on the quality of the crystal measured. Thestructure obtained allows the identification of the (paramagnetic) compound, as well asproviding the input data for the computation of the CF splitting using ab initio methods.

A new family of Ln-based SMM will be presented of general formula [LnIII(18-c-6)(X4Cat)(NO3)]·MeCN where Ln = Ce, Nd, Tb, Dy and X = Cl, Br. The problematic crystalstructure determination of the brominated series will be emphasised and solutions totwinning, poor diffraction and radiation damage, found using the MX1 and MX2 beamlinesat the Australian Synchrotron, will be discussed.

Crystal transformation and meta-stable forms of a tetramorphicone-dimensional coordination polymer of cadmiumdithiophosphate with a bipyridine linkerTan, Yee Seng1; Tiekink, Edward R.T.1

1Research Centre for Crystalline Materials, School of Science and Technology, SunwayUniversity, No5, Jalan Universiti, Bandar Sunway, 47500 Selangor Darul Ehsan, Malaysia.

The recent discovery of a one-dimensional coordination polymer formed by linking a binarycadmium dithiophosphate with a bipyridine linker, has shown temperature-dependentsingle-crystal-to-single-crystal transformation phenomena. The room temperature form of{Cd[S2P(OMe)2]2(4-pyridine-aldazine)}n, form α, will transform to a 100 K stable form, formβ, by gradually cooling the crystal. This transformation is in fact reversible. Further, twoforms, forms γ and δ, were also discovered when crystals were placed directly on thediffractometer in the cryo-stream at 100 K. The meta-stable forms, δ and γ, revert, non-reversibly, to the α form by warming the crystal slowly. Cooling the form resulted in theformation of form at around 240 K (DSC); gradual cooling and warming results inreversible transformations between the α and β forms. The crystal symmetry of the fourforms are quite distinct and changes are evident in their respective molecular structures.The main structural differences apparent are the planarity of the metalloaromatic ring of theCdS2P chromophore and the torsion angle in the link connecting the two pyridyl residues.

Engineering of Photoreactivie and Photosalient CrystalsVittal, Jagadese J.

1Department of Chemistry, National University of Singapore, SINGAPORE 117543, E-mail:chmjjv@nus.edu.sg

Mechanically responsive materials change their shape and size or move in space by light,thermal, pressure or chemical energy. Of these, dynamic molecular crystals undergovarious movements like curling, crawling, jumping, leaping, hopping, popping, splitting,wiggling, and exploding, when exposed to heat (thermosalient effect) or light (photosalienteffect). These photo-dynamic and thermal-dynamic crystals create new ways oftransforming light and heat energy into mechanical work. These effects are similar topopping of mustard seeds on hot oil and corn on hot surfaces. Usually anisotropic volumechanges accompanied by the sudden release of the accumulated strain energy areresponsible for the salient effects by heat and light. On the contrary, it was ratherchallenging to synthesize photoreactive solids that can undergo photodimerization reactionof metal complexes, coordination polymers (CPs) and metal-organic frameworks (MOFs), inthe past. But it is now possible to design a reactive solid using the crystal engineeringprinciples with ease. While investigating the [2+2] photoreactivity of crystals under UV light,we observed violent popping of single crystals of several metal complexes under UV light(Figure 1). In this talk we will discuss the design of some of these photoreactive crystals toexhibit photosalient behavior.

Figure.1. A schematic diagram showing the photosalient behavior under UV light.

MS#18

Novel applications of crystallography

Solvothermal reactor for in-situ synchrotron radiation powderdiffraction at SPring-8 BL02B2 for quantitative design fornanoparticle.Fujita, Tomoki1; Kasai, Hidetaka1,2; Nishibori, Eiji1,2

1 Graduate School of Pure and Applied Sciences, University of Tsukuba, Japan2 Faculty of Pure and Applied Sciences and Tsukuba Research Center for Energy MaterialsScience, University of Tsukuba, Japan

Design and synthesis of size and shape controlled functional nano-particle have attractedattention owing to their huge potential for practical applications. Size and shape of nano-particle have been characterized by nano-meter scale probe, such as scanning andtransmission electron microscopy, and X-ray and neutron diffraction. Among them, an X-rayis the most convenient and powerful probe owing to the transmittance of the sample cell,etc. We have designed a solvothermal reactor for nanoparticle synthesis and installed thereactor for in-situ synchrotron radiation powder diffraction experiment at SPring-8 BL02B2beamline. The reactor system has high reproducibility of data assisted by the oscillationmeasurement system with a vibrator which contributes to measure homogeneous intensitydistribution of Debye Scherrer ring. In-situ powder diffraction study of Ce(NO3)36H2O wasdescribed to show the performance of the reactor. Three dimensional diagram usingpressure, temperature and particle size of CeO2 nanoparticles were determined by thesystem. The pressure and temperature dependence of particle formation speed, latticeconstants, and particle size were clearly determined as a reproducible result. The presentin-situ system will be used to optimize synthesis condition for functional nano-particle.

Figure.1. Photograph of the reactor installed at SPring-8 BL02B2 beamline

Dynamic Compression at Pohang X-ray Free Electron Laser Facility (PAL-XFEL) Huijeong Hwang, Yongjae Lee1,2 1Department of Earth System Sciences, Yonsei University, Seoul, Korea 2Center for High Pressure Science and Technology Advanced Research, Shanghai, China

We have successfully commissioned dynamic compression studies at the Pohang X-ray Free Electron Laser facility (PAL-XFEL) in Korea by utilizing instrumentations at FXS (Femtosecond X-ray Scattering) – XSS (X-ray Scattering and Spectroscopy) beamline. As the first experiment, a polycrystalline iron foil has been illuminated by an 800 nm wavelength uncompressed optical laser with ~6 mJ in 150 ps pulse length, focused onto a 60 m FWHM spot. The shock-compressed sample has then been probed by ca. 50 fs quasi-monochromatic (bandwidth 0.4%) X-ray pulse at an energy of ~10 keV with 1011 photons per pulse, focused to ca. 30 m diameter using a CRL optics. The sample is positioned normal to the X-ray pulse at a distance of ca. 12 cm from a Rayonix mx225 detector in a way to cover 2angles up to ca. 65 degrees. Single-shot diffraction measurements were performed with ca. 100 ps. increment up to one nanosecond. We demonstrate that PAL-XFEL can provide a unique opportunity in probing ultrafast lattice dynamics with sufficient spatial and temporal resolution in intermediate pressure regime.

Hexamethylbenzene: Ant or Elephant? A 3D Bendable Crystalwith Giant Power Output Capability

Liang Li 1, Patrick Commins 1, Stefan Schramm1, Pance Naumov1*

1 New York University Abu Dhabi, Abu Dhabi, United Arab Emirates.

The structure of Hexamethylbenzene (HMB) crystal (Phase II) has been a milestone in thehistory of crystallography and organic chemistry[1]. After the reports of the high temperature(Phase I) [2] and low temperature phase (Phase III)[3]. The room temperature phase (II) tohigh temperature phase (I) transition mechanisms are studied intensively[4]. Phasetransition is a result of energy transform either from thermal, mechanical or other forms ofenergy to chemical energy. We investigated the well-studied Hexamethylbenzene singlecrystal phase transition and found it release a mechanical force 10,000 times over itsweight which is dominate comparing with other common weight lifting animals. (Figure 1)Meanwhile, the crystal is three dimensional bendable and mechanical force inducedreversible simultaneous multiple domains generation was observed.

Figure1. The schematic expending and rotation during the phase transition and the released mechanical force.

[1] K. Lonsdale, Nature 1928, 122, 810.

[2] W. Tokunosuke, S. Yoshihiko, C. Hideaki, Scientific papers from the Osaka University 1959.

[3] J. Stride, Acta Crystallographica Section B 2005, 61, 200-206.

[4] Y. V. Mnyukh, N. A. Panfilova, N. N. Petropavlov, N. S. Uchvatova, Journal of Physics and Chemistry

of Solids 1975, 36, 127-144.

Investigation of crystal structure of reduced ceria underhydrogen by powder neutron diffractionMatsukawa, Takeshi; Hoshikawa, Akinori; Ishigaki, Toru

Frontier Research Center for Applied Atomic Sciences, Ibaraki University.

The redox reaction of cerium dioxide (CeO2: ceria) during thermal treatment underhydrogen produces oxygen vacancies caused by the change in the valence of ceriumatoms. In this study, to elucidate the kinetical structural change of ceria under reducingcondition, we investigated the crystal structure depended on the isothermal holding time.Under a hydrogen atmosphere at high temperature, we observed that ceria was reducedand its color of ceria changed from white to blue. Depending on the isothermal holdingtime, the subsequent oxidation process when the samples were returned to roomtemperature and exposed to air. In the case of a long holding time (20 h), the colorimmediately changed from blue to white, while for a short holding time (30 min), the bluecolor was maintained. The crystal structures of ceria in a hydrogen atmosphere between800°C and 200°C were studied by powder neutron diffraction. The blue-color ceria went aredox reaction to produce the oxyhydroxide ceria (CeO2Hy, 0≦y≦1), which changedcerium valence (CeIV → CeIII), as shown in Figure 1. Ceria was kinetically reduced inhydrogen depending on the isothermal holding time, and the crystal phase of CeO2H wasprecipitated during the short isothermal holding time. We also observed a temperature-dependent reduction of the oxyhydroxide, to form the oxygen vacant phase CeO2-x

(0≦x≦0.5).

Figure 1. Crystal structure of oxyhydroxide ceria.

The effect of pressure, temperature and gas uptake withinfullerene stabilised phthalocyanine nanoporous molecularcrystalsMoggach, Stephen1; Bezzua, Grazia2; Burt, Luke2; McMonagle, Charlie2; Kariuki, Benson3;Allan, David4; Warren, Mark4; McKeown, Neil2

1 School of Molecular Sciences and Centre for Microscopy Characterisation and Analysis,The University of Western Australia, 35 Stirling Hwy, Crawley, WA 6009, Australia2EastChem, School of Chemistry, University of Edinburgh, David Brewster Road,Edinburgh, EH9 3FJ, UK.3School of Chemistry, Cardiff University, Cardiff, CF10 3AT, UK.4Diamond Light Source, Didcot, Oxon, OX11 0DE, UK.

Porous molecular systems are of increasing interest due to their complementary propertiesto those of conventional porous materials such as MOFs.[1] One important aspect for allporous materials is their structural stability, however, the relatively weak intermolecularinteractions within porous molecular crystals typically do not provide the environmentalstability of a structural framework based on chemical bonds. [2] Another element of porousmaterials that has been found to greatly increase gas storage and selectivity is to haveaccessible sites of chemisorption that can be activated. [3] Here we report the exceptionalstability of porous molecular crystals that owe their stability to the co-crystallisation of ametal containing phthalocyanine derivative with a fullerene (Fig. 1). These crystals retaintheir porous structure on heating (500K), during prolonged immersion in boiling aqueousacid or base and at extreme pressures (>4 GPa). The cubic crystals contain extremelylarge (8 nm3) interconnected solvent filled voids while the stabilizing fullerene is heldbetween two phthalocyanines in a “ball and socket” arrangement. In this way, access to thereactive open metal site is maintained via the solvent accessible voids. Investigation ofthe effect of pressure, gas uptake and chemisorption of CO and O2 onto the open metalsite has been investigated directly via in-situ XRD measurements. Initial results with aCobalt phthalocyanine derivative, demonstrate that CO and O2 bind efficiently but reversiblyto the Co2+ cation at very low gas pressures (0.2 atm, see Fig. 2). The combinationreversible chemisorption binding within a porous material composed of highly functionalcomponents suggests applications in chemical sensors, photovoltaics and photocatalysis,for which the stability demonstrated in this study will be beneficial. [4]

[1] G. Maurin, C. Serre, A. Cooper, G. Ferey, Chem. Soc. Rev. 2017, 46, 3104-3107.[2] A. G. Slater, A. I. Cooper, Science (New York, N.Y.) 2015, 348, aaa8075.[3] J. Bentley, G. S. Foo, M. Rungta, N. Sangar, C. Sievers, D. S. Sholl, S. Nair,

Industrial & Engineering Chemistry Research 2016, 55, 5043-5053.[4] G. Bottari, G. de la Torre, D. M. Guldi, T. Torres, Chem. Rev. 2010, 110, 6768-6816.

Quantum Dynamics of the [2Fe-2S] Composite 54.7°-Helix Nanostructure of Vegetable Fibers Nguyen Van Tri

Institute of Engineering Physics, Hanoi University of Science and Technology,

Hanoi, Vietnam

Over a long period of time, using ESR in combination with some traditional methods, we revealed that vegetable fibers own a very peculiar structure. Their inside is constituted not only by polysaccharide cellulose, but also by another extremely important component consisting of the composite aperiodic fivefold [2Fe-2S] metal-organic super-exchange combinations diagonally linking the cellulose chains in the elementary fibrils f (Fig. 1). And a lot of fibrils f spiral about the axis of a macrofiber F by the sloping angle θ0 = 54.7°. This fivefold metal-organic nanostructure plays a decisive role in the specific features of vegetable fibers [1-3}

Our present paper aims to the Quantum Dynamics Behavior of the 54.7°-Helix structure of vegetable fibers. In the [2Fe-2S] combination, the active Iron ion Fe (3d5) is in the center of a fivefold orthoprism formed by 10 neighboring Sulfur legends S (Fig. 1). The crystal field in the prism splits up five 3d energy levels with the splitting factor D(3cos2θθθθ - 1), here θ is the the angle by which the applied field (e.g. electric or magnetic) deflects from the axis of the crystal field. However, the statistical effective value <θ> in the 54.7°-Helix structure is just equal to θ 0 = 54.7°, so the splitting factor is annuled! Thus, the 54.7°-Helix nanostructure makes its active electron system to become a quantum degenerating system. That is the prerequisite for wonderful features of vegetable fibers, such as the full and stable response of plants to radiation (e.g. light), the effect of natural laser of plants experimentally recorded at the vegetable body temperature (~ 40°C) [3], etc.

[1] Nguyen Van Tri et al. (2001) J. Ferroelectrics 250, 265-268. [2] Nguyen Van Tri (2008) IUCr XX, Acta Cryst. A64, C473. [3] Nguyen Van Tri (2009) Springer Proceedings in Physics 127, 51-60.

f

a

b

c

S

S

Fe

Fig. 1. Model of the elementary cell (unit cell) of the composite fivefold [2Fe-2S] aperiodic crystal in the Vegetable Fibers: γ = (b,a) = 72°, c // f , a = b = 8.18 Ǻ, c = 10.51 Ǻ. A chain of such elementary cells link the 9 cellulose chains above with the 9 ones below.