chemical biology of ion transport - chemistry.msu.edu · chemical biology of ion transport...

55
Chemical Biology of Ion Transport Van Nguyen 1

Upload: others

Post on 01-Jun-2020

25 views

Category:

Documents


0 download

TRANSCRIPT

Chemical Biology of Ion TransportVan Nguyen

1

Chemical biology of ion transport

Background

Viral transport

Bacterial transport

Eukaryotic transport

2

Ion transport across cell membranes

ATP ADP + Pi

ClosedOpen

ATP-powered pump100 – 103 ions/sActive transport

Ion channel107 – 108 ions/sPassive transport

Transporter102 – 104 ions/s

Responsible for: • transepithelial transport of salt and water• regulation of cytoplasmic or vesicular ion concentration • regulation of cellular volume and pH• chemical signaling

Marieb, E.N; Hoehn, K. Human anatomy and physiology; Pearson: New York, 2013. 3

simple diffusion ion carrier ion channel

Chemical biology of ion transport BackgroundViral transportBacterial transportEukaryotic transport

4

Influenza A entry mechanism

5

Under acidic condition: • Endosomal membrane fuses with viral envelope• M1 protein releases virus RNA, allow virus to replicate in nucleus

Imagestakenfromwww.virology.ws

H+

H+

M1M2

M2 transmembrane segment

• 4 parallel monomers • Regulate pH by transporting proton• Crucial for viral replication

6Pielak, R. M; Chou, J. J. Biochim. Biophys. Acta, 2011, 1808, 522-529.

Inhibitors of M2NH2

H2N

Amantadine

Rimantadine

7

Amantadineor Rimantadine

• Approved by FDA in 1976 • No longer effective

Tisdale, M. Antimicrobial drug resistance; Springer, 2009

Image taken from www.virology.ws

Water network in M2 transmembrane segment

8

viral exterior

Val27 valve

Ala30, Ser31

Ala34

Entry cluster

His37 box

Bridging cluster

Trp basket

Exit cluster

Asp44, Arg45

Acharya, R.; Carnevale, V.; Fiorin, G.; Levine, B. G.; Polishchuk, A.L.; Balannik, V.; Samish, I.; Lamb, R. A.; Pinto, L. H.; DeGrado, W. L.; Klein, M. L. Proc. Natl. Acad. Sci., 2010, 107, 15075-15080

G34A mutant

Asymmetrical transport activity of M2

9

Acharya, R.; Carnevale, V.; Fiorin, G.; Levine, B. G.; Polishchuk, A.L.; Balannik, V.; Samish, I.; Lamb, R. A.; Pinto, L. H.; DeGrado, W. L.; Klein, M. L. Proc. Natl. Acad. Sci., 2010, 107, 15075-15080

pH 8.2 pH 6.5 pH 5.01st His37 protonated

decreasing pH

3rd His37 protonated 4th His37 protonated

Val27

His37

Trp41

Water network in M2TM

10Thomaston, J. L.; Alfonso-Prieto, M.; Woldeyes, R. A.; Fraser, J. S.; Klein, M. L.; DeGrado, W. F. Proc. Natl. Acad. Sci., 2015, 112, 14260-14265.

Cryogenic temperatureHigh pH Low pH

Room temperatureHigh pH Low pH

Val27

Ser31

Gly34

His37

Trp41

Val27

Ser31

Gly34

His37

Trp41

16.8 Å

Water network in wild-type and S31N mutant M2

11

S31N natural mutant of M2 wild-type M2

Acharya, R.; Carnevale, V.; Fiorin, G.; Levine, B. G.; Polishchuk, A.L.; Balannik, V.; Samish, I.; Lamb, R. A.; Pinto, L. H.; DeGrado, W. L.; Klein, M. L. Proc. Natl. Acad. Sci., 2010, 107, 15075-15080.Thomaston, J. L.; Alfonso-Prieto, M.; Woldeyes, R. A.; Fraser, J. S.; Klein, M. L.; DeGrado, W. F. Proc. Natl. Acad. Sci., 2015, 112, 14260-14265.Thomaston, J. L.; DeGrado, W. F. Protein Sci. 2016, 25, 1551-1554.

Asn31 box by H-bonding

Amantadine binding pocket in wild-type M2

12

Gly34

Ser31

pH5.3 pH7.5

Das, K.; Aramini, J. M.; Ma, L.; Krug, R. M.; Arnold, E. Nature Struc. Mol. Biol. 2010, 17, 530-538.

Amantadine in S31N mutant M2

13

• Replacing serine by asparagine:• More hydrophilic – reduce interaction

with hydrophobic cage of amantadine • Longer chain – steric hindrance to drug

binding pocket

Das, K.; Aramini, J. M.; Ma, L.; Krug, R. M.; Arnold, E. Nature Struc. Mol. Biol. 2010, 17, 530-538. Thomaston, J. L.; Alfonso-Prieto, M.; Woldeyes, R. A.; Fraser, J. S.; Klein, M. L.; DeGrado, W. F. Proc. Natl. Acad. Sci., 2015, 112, 14260-14265.Thomaston, J. L.; DeGrado, W. F. Protein Sci. 2016, 25, 1551-1554.

NH2

Asn31

ONH3

O

HO

Serine

ONH3

O

AsparagineO

H2N

Developing M2 inhibitors of S31N influenza A

14

Approach 1: Introduce direct/water mediated H-bonding or electrostatic interactions with backbone of M2 channel

to induce conformational change of Asn31Approach 2: Increase the polarity to enhance binding affinity

of adamantyl group

Wang, J.; Wu, Y.; Ma, C.; Fiorin, G.; Pinto, L.H.; Lamb, R.A.; Klein, M. L.; DeGrado, W. F. J. Med. Chem. 2013, 56, 2804-2812Thomaston, J. L.; DeGrado, W. F. Protein Sci. 2016, 25, 1551-1554

NH2 HN

warhead

Amantadine

Approach 1

Approach 2

To overcomeS31N resistance

Developing M2 inhibitors of S31N influenza A

15

effective inhibitor of S31N

Wang, J.; Wu, Y.; Ma, C.; Fiorin, G.; Pinto, L.H.; Lamb, R.A.; Klein, M. L.; DeGrado, W. F. J. Med. Chem. 2013, 56, 2804-2812Li, F.; Ma, C.; DeGrado, W. F.; Wang, J. J. Med. Chem. 2016, 59, 1207-1216

V27

N31

G34

H2N

ON

S

Inhibitor development strategy

16

Li, F.; Ma, C.; DeGrado, W. F.; Wang, J. J. Med. Chem. 2016, 59, 1207-1216

H2N

ON

SS

OO

NO

N NO

N NS

SN

OH

OH OH HOOH

oxazole oxadiazole thiadiazole thiazole

Potential inhibitors of S31N Influenza A

HN

ON

S

HN

ON

S

HN

ON

S

HN

ON

S

OHOH OH OH

HO

H3CO

30b 30f 30g 30h

17Li, F.; Ma, C.; DeGrado, W. F.; Wang, J. J. Med. Chem. 2016, 59, 1207-1216

% p

laqu

e fo

rmat

ion

log(X nM)

30g EC50 = 404 nM30f EC50 = 510 nM30b EC50 = 727 nM30h EC50 = 2500 nM

Chemical biology of ion transport

BackgroundViral transportBacterial transportEukaryotic transport

18

M2 channel Influenza A

Siderophores – iron chelating agents in bacteria

• Produced by bacteria under iron-depriving conditions• Couple with specific receptor protein to transport siderophore-iron

complex into cell• Essential for bacteria to establish host-parasite relationship in mammalian

cells

19Nagota, B.; Vedpathak, D. Eur. J. Gen. Med., 2011, 8, 229-235Raymond, K. N.; Allred, B. E.; Sia, A. K. Acc. Chem. Res. 2015, 48, 2496-2505

Second siderophore, iron loaded

initially bound siderophore, iron free

Outer membrane Receptor

A

CD

B

Release

iron loaded, siderophore binding

Conformationalchange

Fe3+

exchange

20

Classes of siderophores

Raymond, K. N.; Allred, B. E.; Sia, A. K. Acc. Chem. Res. 2015, 48, 2496-2505

Enterobactin

O

O

O

O

O

O

NHHN

HN

O

O

O

OHOH

OHOH

HO

HO

Catecholates

HNN

NHO O NHO

O

O OH

HO

OH

HN N

NH

N

CO2H

OH

O

OO

O

OHOH

CO2H

CO2H

Hydroxamates Carboxylates

Enterobactin-iron complex

∆ - enterobactin21Raymond, K. N.; Dertz, E. A.; Kim, S. S. Proc. Natl. Acad. Sci., 2003, 100, 3584-3588

O

O

O NH

FeO

O O

O

HN O

O

OO

O

O

O

Kd = 1052 M-1

O

O

O

O

O

O

NHHN

HN

O

O

O

OHOH

OHOH

HO

HO

Siderophores as treatment for iron overload diseases

• Iron overload caused by:• Blood transfusions required to prevent anaemias, such as

thalassemia major• Genetic defects that increase iron absorption from diet

• Main criteria of ideal iron chelator• High affinity for iron and chelating efficiency• Oral bioavailability • Tissue and cell penetration

22Crisponi, G.; Remelli, M. Coor. Chem. Rev., 2008, 252, 1225-1240

Most natural siderophores unqualified to be drug

Lipinski’s rule:• Molecular weight: 500 • logP < 5• H-bond donors: 5• H bond acceptors: 10

23

MW: 564 logP < 3H-bond donors: 8H bond acceptors: 14

MW: 404logP < 3H-bond donors: 6H-bond acceptors: 12

MW: 669 logP < 3H-bond donors: 9H bond acceptors: 18

Crisponi, G.; Remelli, M. Coor. Chem. Rev., 2008, 252, 1225-1240

O

O

O

O

O

O

NHHN

HN

O

O

O

OHOH

OHOH

HO

HO

Catecholates

HNN

NHO O NHO

O

O OH

HO

OH

HN N

NH

N

CO2H

OH

O

OO

O

OHOH

CO2H

CO2H

Hydroxamates Carboxylates

Current drug treatment for iron overload diseases

24Crisponi, G.; Remelli, M. Coor. Chem. Rev., 2008, 252, 1225-1240

H2N N

OH

O

NH

O

N

O

HN

O

NOH

O CH3

DesferalIsolated from

Streptomyces pilosus

N

O

CH3

OH

CH3

Deferiprone

N

N

N

OH HO

ICL670 or Exjade

OH

OOH

Discovery of siderophore-peptide antibiotic MccE492m

25

cSGSG SSSTASNYGS GSGNWSPGILVPIPVNVPGH DILGQGVTQLAGGAAGLAAS GLGGPAGLAAGWAMNNGLDN LLQTNPDTEG

MccE492Peptide antibiotic

Linear enterobactin-MccE492 conjugate with greater antibiotic potency, found in K. pneumoniae

cSGSG SSSTASNYGS GSGNWSPGILVPIPVNVPGH DILGQGVTQLAGGAAGLAAS GLGGPAGLAAGWAMNNGLDN LLQTNPDTEG

MccE492m

Lorenzo, V.; Pugsley, A. P. Antimicro. Age. Chemo. 1985, 27, 666-669

OHOO O

O

OHN

NHHN

O

O

O

OHOH

HO

HO

OHOH

OH

O

HOHOHO

OO

Iron transport by enterobactin in E. coli

26

Outer membrane

Cytoplasm membrane

Fep A

Fep B

channelATPase FepC

Fes

ExbD

ExbB

TonB

FepG

FepD

Raymond, K.N.; Dertz, E. A.; Kim, S. S. Proc. Natl. Acad. Sci., 2003, 100, 3584-3588

O

O

O

O

O

O

NHHN

HN

O

O

O

OHOH

OHOH

HO

HO

HOHN

O

OHO

OH

OH

3

O

O

O NH

FeO

O O

O

HN O

O

OO

O

O

O

O

O

O NH

FeO

O O

O

HN O

O

OO

O

O

O

Fe3+

Enterobactin

Kd(FeEnt-FepA) = 0.2 nM

Siderocalin as a challenge for enterobactin-antibiotic conjugates

27

• Siderocalin – human immuno protein• First line of defense against bacteria• Trapping enterobactin by binding

2,3-catechol amides• Kd(FeEnt-siderocalin) = 0.4-0.5 nM

Raymond, K. N.; Allred, B. E.; Sia, A. K. Acc. Chem. Res., 2015, 48, 2496-2505

K134

K125

R81

O

O

O

O

O

O

NHHN

HN

O

O

O

OHOH

OHOH

HO

HORaymond, K.N.; Dertz, E. A.; Kim, S. S. Proc. Natl. Acad. Sci., 2003, 100, 3584-3588

Glucosylated enterobactin

28

Salmochelin S4 or diglucosylated enterobactin

(DGE) found in Salmonella species and

other pathogenic bacteria

monoglucosylated enterobactin(MGE)

Glucose increases steric of enterobactin, avoiding captured by siderocalin

Chairatana, P.; Zheng, T.; Nolan, E. M. Chem. Sci., 2015, 6, 4458-4471

O

O

O

O

O

O

NHHN

HN

O

O

O

OHOH

OHOH

HO

HO

O

OHHOHO

OH

O

O

O

O

O

O

NHHN

HN

O

O

O

OHOH

OHOH

HO

HO

O

OHHOHO

OH

O OH

OHHO

HO

Antibiotic-ent-glc conjugates

29Chairatana, P.; Zheng, T.; Nolan, E. M. Chem. Sci., 2015, 6, 4458-4471

O

O

O

O

O

O

NHHN

HN

O

O

O

OHOH

OHOH

HO

HO

O

HNON

N NONH

O

NsCO2H

HO

R

3

R = H: AmpicillinR = OH: Amoxicillin

hydrolyzable group O OH

OHHO

HO

O OH

HO OHHO

diglucosylated-enterobactin-antibiotics (DGE)

Antibiotic activity against human pathogenic E. coli

30

Amp-Ent-diGlu is 1000-fold more active than Ampicilin

Chairatana, P.; Zheng, T.; Nolan, E. M. Chem. Sci., 2015, 6, 4458-4471

CFT073 UTI89

OD

600

OD

600

0.16

0.12

0.08

0.04

0.00

0.20

0.00

0.05

0.10

0.15

0 010-10 10-9 10-8 10-7 10-6 10-5 10-4

Concentration (M)10-10 10-9 10-8 10-7 10-6 10-5 10-4

Concentration (M)

ampicillinenterobactin-ampicillin

monoglucosylated enterobactin-ampicillindiglucosylated enterobactin-ampicillin

Human pathogenic vs. non-pathogenic E. coli

31

Ec K-12 vs CFT073 Ec K-12 vs UTI89

CFU

/mL

Chairatana, P.; Zheng, T.; Nolan, E. M. Chem. Sci., 2015, 6, 4458-4471

CFU

/mL

1010

109

108

107

106

105

104

Ec K-12 Ec CFT073 Ec K-12 Ec CFT073 Ec K-12 Ec CFT073 Ec K-12 Ec CFT0731:1 mixed culture 1:1 mixed culture

1010

109

108

107

106

105

104

untreatedampicillinenterobactin-ampicillin

monoglucosylated enterobactin-ampicillin

diglucosylated enterobactin-ampicillin

Biosynthesis of enterobactin

32Gehring, A. M.; Bradley, K. A.; Walsh, C. T. Biochemistry., 1997, 36, 8495-8503

O OH

OHO

O

OH

O OH

OHO

O

OH

OHO OH

OH

OH

O OH

OH

OH O

O

O

O

O

O

NHHN

HN

O

O

O

OHOH

OHOH

HO

HO

Ent Cisochorismate

synthetase, Mg2+

Ent B2,3-dihydro-2,3-

dihydroxybenzoate synthetase

Pyruvate

Ent A, NAD+

2,3-dihydro-2,3-dihydrobenzoate dehydrogenase Ent E,F,D

L-Lysine

Ent E: 2,3-dihydroxybenzoate- AMP ligaseEnt D: phosphopantetheinyl transferaseEnt F: seryl-AMP ligase

H2N

NH3

O

O

L-Lysine

Chemoenzymatic synthesis of glucosylated enterobactin

33Lee, A. A.; Chen, Y. S.; Ekalestari, E.; Ho, S. Y.; Hsu, N. S.; Kuo, T. F.; Wang, T. A. Angew. Chem. Int. Ed. 2016, 55, 12338-12342

OCl

NO2

OOH

HOHO

HO OOH

HOHO

UDPHO

UDP

OCl

NO22-chloro-4-nitrophenyl glycoside

O NONH

O

OPO

OO

PO

OHO

UDP-Glc

UDP =

oleandomycinglycosyltransferase

Chemoenzymatic synthesis of glucosylated enterobactin

34Lee, A. A.; Chen, Y. S.; Ekalestari, E.; Ho, S. Y.; Hsu, N. S.; Kuo, T. F.; Wang, T. A. Angew. Chem. Int. Ed. 2016, 55, 12338-12342

O

O

O

O

O

O

NHHN

HN

O

O

O

OHOH

OHOH

HO

HO

O

O

O

O

O

O

NHHN

HN

O

O

O

OHOH

OHOH

HO

HO

OOH

OH

HOHOUDP-Glc

UDP

enterobactin(Ent) R2

glucosyltransferase

R1

R1 R2 ProductH

GlcGlc

HH

Glc

(Glc)1Ent(Glc)2Ent(Glc)3Ent

Chemical biology of ion transport

BackgroundViral transportBacterial transportEukaryotic transport

35

M2 channel Influenza A

EnterobactinE. coli

What is cystic fibrosis?

• A genetic disease • Persistent lung infections• U.S.: 30,000 patients• Worldwide: 70,000 patients• 1,000 new cases diagnosed with cystic fibrosis each year

36

Cystic fibrosis transmembrane conductance

37

• Cystic fibrosis transmembrane conductance regulator (CFTR gene) is mutated

• Defective chloride ion channel• Disrupting mucus flow• Clogging airway and trapping bacteria• Surface of lung cell dehydrated

Restoring CFTR chloride channel as CF treatment

ATP ADP + Pi

ClosedOpen

ATP-powered pump100 – 103 ions/sActive transport

Ion channel107 – 108 ions/sPassive transport

Transporter102 – 104 ions/s

Marieb, E.N; Hoehn, K. Human anatomy and physiology; Pearson: New York, 2013. 38

simple diffusion ion carrier ion channel

Synthetic anionphores

Synthetic ion channel

Strategy 1: Amphotericin B as ion channel• Isolated from Streptomyces nodosus in 1955• Highly effective antifungal• Kill fungi by binding and forming a channel to

permeabilize cell membranes• Non-selective ion channel

39Wildeman, E. L.; Gonen, T.; Rienstra, C. M.; Burke, M. D. Nature. Chem. Biol., 2014, 10, 400-406.Palacios, D. S.; Anderson, T. M.; Burke, M.D. J. Am. Chem. Soc., 2007, 129, 13804-13805.

O

OH

OH

OH

OMe

HO CO2H

HO

HO

OH

MeHO Me

O O

OH NH2OH

Me

Amphotericin BAmB

mycosamine

Derivative of AmB to study ion channel activity

O

OH

OH

OH

OMe

HO CO2H

HO

HO

OH

MeHO Me

O O

OH NH2OH

Me

Amphotericin BAmB

O

OH

OH

OH

OMe

HO CO2H

HO

HO

OH

MeHO Me

OH

mycosamine

AmdeBno mycosamine

O

OH

OH

OH

OMe

HO CO2H

HO

HO

OH

MeH Me

O O

OH NH2OH

Me

mycosamine

C35deOAmBno OH at C35

3535

40

Wildeman, E. L.; Gonen, T.; Rienstra, C. M.; Burke, M. D. Nature. Chem. Biol. 2014, 10, 400-406.

Channel activity of AmB and derivatives

41

Only AmB show channel activityby releasing K+

Gray, K. C.; Palacios, D. S.; Dailey, I.; Endo, M. M.; Uno, B. E.; Wilcock, B. C.; Burke, M. D. Proc. Natl. Acad. Sci., 2012, 109, 2234-2238.

DMSOAmB 1µM

C35deOAmB 1µMC35deOAmB 10µM

Perc

ent o

f Max

K+

Rele

ase

100

90

80

70

60

50

40

30

20

10

00 1 2 3 4 5 6

Time (min)

Derivative of AmB to study ion channel mechanisms

O

OH

OH

OH

OMe

HO CO2H

HO

HO

OH

MeHO Me

O O

OH NH2OH

Me

Amphotericin BAmB

O

OH

OH

OH

OMe

HO CO2H

HO

HO

OH

MeHO Me

OH

mycosamine

AmdeBno mycosamine

O

OH

OH

OH

OMe

HO CO2H

HO

HO

OH

MeH Me

O O

OH NH2OH

Me

mycosamine

C35deOAmBno OH at C35

3535

42

no channel formation

Wildeman, E. L.; Gonen, T.; Rienstra, C. M.; Burke, M. D. Nature. Chem. Biol. 2014, 10, 400-406.Cioffi, A. G.; Hou, J.; Grillo, A. S.; Diaz, K. A.; Burke M. D. J. Am. Chem. Soc. 2015, 137, 10096-10099.

AmB restores activity of defective yeast S. cerevisiae

43

• S. cerevisae yeast missing trk1∆trk2∆ potassium transporters –can’t growth

• Minimum concentration of AmB required to restore growing rate of yeast is 0.125 µM

trk1∆trk2∆ + AmBtrk1∆trk2∆ + C35deOAmB

concentration (µM)

OD

600

max

OD

600

wildtype

trk1∆trk2∆

43

trk1∆trk2∆+AmB

NS

Cioffi, A. G.; Hou, J.; Grillo, A. S.; Diaz, K. A.; Burke M. D. J. Am. Chem. Soc. 2015, 137, 10096-10099.

1.21.0

0.80.60.4

0.20.0

1.21.0

0.80.60.4

0.20.0

1.4

1.21.0

0.80.6

0.4

0.20.0

0 0.25 0.5 0.75 1

AmB restores CFTR Cl channel in NuLi epithelia cell line

44

11 µm

3 µm

best concentration: 0.5 µM

normal human lung epithelia

CF patients lung epithelia

CF patients lung epithelia + AmB

Burke, M. D.; Cioffi, A. G.; Diaz, K. A.; Hou, J.; Grillo, A. U.S Patent WO2016073462, 2016

Strategy 2Synthetic anionphores

• Small molecule – drug like• Oral bioavailability• Self-organized to bind chloride selectively• Cell membrane permeability • Relatively effective formation and transport rate in

lipid bilayer• Measured by Ka and transporter:lipid ratio

45

Cholapod-based synthetic anionphores

46

OH

O

HOOH

OH

cholic acidY

O

ROX

X

McNally, B. A.; Koulov, A. V.; Lambert, T. N.; Smith, B. D.; Joos, J. B.; Sisson, A. L.; Clare, J. P.; Sgarlata, V.; Judd, L. W.; Magro, G.; Davis, A. P. Chem. Eur. J. 2008, 14, 9599-9606. Li, H.; Valkenier, H.; Judd, L. W.; Brotherhood, P. R.; Hussain, S.; Cooper, J. A.; Jurcek, O.; Sparkes, H. A.; Sheppard, D. N.; Davis, A. P. Nature Chem., 2015, 8, 24-32.

X

NH

O

NH N

H

O

NH

NO2

NH

O

NH

CF3

NH

S

NH

NH

S

NH

NO2

NH

S

NH

CF3

YO

CH3O

O

CF3NH

SOO NH

NO2

H-bond donors

X

NH

O

NH N

H

O

NH

NO2

NH

O

NH

CF3

NH

S

NH

NH

S

NH

NO2

NH

S

NH

CF3

47

Y

O

ROX

X

Increase binding affinity

Increase binding affinity

YO

CH3O

O

CF3NH

SOO NH

NO2

Binding affinity vs. transport rate

48

Y

O

ROX

X

increase binding affinity

increase transport rate

SOO NH

NO2

O

CF3NH

O

CH3O

Y

Candidate of cholapod-based anionphores

49

Lipinski’s rule:Molecular weight: 500 logP < 5H-bond donors: 5H bond acceptors: 10

Molecular weight: > 700 logP = 8, too lipophilicH-bond donors: 5H bond acceptors: 10Ka > 1011 M-1 (first-order rate)Transporter:lipid ratio = 1:25000Slow movement across membrane

NH

O

H3COHN

HN

O

CF3

SS

HNHN

CF3

CF3

Li, H.; Valkenier, H.; Judd, L. W.; Brotherhood, P. R.; Hussain, S.; Cooper, J. A.; Jurcek, O.; Sparkes, H. A.; Sheppard, D. N.; Davis, A. P. Nature Chem., 2015, 8, 24-32.

Decalin-based anionphores

NH HN

NH HN

XX

Ar Ar

O OR

X S, O

Ar

CF3F3C CF3 NO2

R -CH3 -C2H5 C8H17

50

Li, H.; Valkenier, H.; Judd, L. W.; Brotherhood, P. R.; Hussain, S.; Cooper, J. A.; Jurcek, O.; Sparkes, H. A.; Sheppard, D. N.; Davis, A. P. Nature Chem., 2015, 8, 24-32.

Potential drug candidates

NH HN

NH HN

OO

O OC2H5

O2N NO2

51

Molecular weight: 569logP = 4.5H-bond donors: 5H bond acceptors: 12Ka > 6.8 x 102 M-1

(first-order rate)Excellent deliverability

Li, H.; Valkenier, H.; Judd, L. W.; Brotherhood, P. R.; Hussain, S.; Cooper, J. A.; Jurcek, O.; Sparkes, H. A.; Sheppard, D. N.; Davis, A. P. Nature Chem., 2015, 8, 24-32.

NH------Cl distance:2.50 – 2.58 Å

Anionphore vs Forskolin

52

Delivery method: inhaled + co-taken with antibiotics to lungs of CF patients

Li, H.; Valkenier, H.; Judd, L. W.; Brotherhood, P. R.; Hussain, S.; Cooper, J. A.; Jurcek, O.; Sparkes, H. A.; Sheppard, D. N.; Davis, A. P. Nature Chem., 2015, 8, 24-32.

NH HN

NH HN

OO

O OC2H5

O2N NO2

1 +

1

Restoring CFTR chloride channel as CF treatment

ATP

ATP-powered pump100 – 103 ions/sActive transport

Ion channel107 – 108 ions/sPassive transport

Transporter102 – 104 ions/s

Marieb, E.N; Hoehn, K. Human anatomy and physiology; Pearson: New York, 2013. 53

NH HN

NH HN

OO

O OC2H5

O2N NO2

O

OH

OH

OH

OMe

HO CO2H

HO

HO

OH

MeHO Me

O O

OH NH2OH

Me

mycosamine

Chemical biology of ion transport

BackgroundViral transportBacterial transportEukaryotic transport

54

M2 channel Influenza A

EnterobactinE. coli

NH HN

NH HN

OO

O OC2H5

O2N NO2

O

OH

OH

OH

OMe

HO CO2H

HO

HO

OH

MeHO Me

O O

OH NH2OH

Me

mycosamine

AcknowledgementDr. John Frost

Dr. Karen DrathsDr. Xuefei Huang

Frost group:Yukari Nishizawa-Brennen

Kelly MillerSwetha Nisthala

55