"phylogeny-driven studies in genomics and metagenomics" talk by jonathan eisen at...
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Phylogeny-Driven Approaches to Genomics and Metagenomics
June 23, 2012Canadian Society for Microbiology
Jonathan A. EisenUniversity of California, Davis
@phylogenomics
Acknowledgements
• $$$• DOE• NSF• GBMF• Sloan• DARPA• DSMZ• DHS
• People, places• DOE JGI: Eddy Rubin, Phil Hugenholtz, Nikos Kyrpides• UC Davis: Aaron Darling, Dongying Wu, Holly Bik, Russell
Neches, Jenna Morgan-Lang• Other: Jessica Green, Katie Pollard, Martin Wu, Tom Slezak,
Jack Gilbert, Steven Kembel, J. Craig Venter, Naomi Ward, Hans-Peter Klenk
Phylogeny: What is it?
Phylogeny: What is it?
• Phylogeny is a description of the evolutionary history of relationships among organisms (or their parts).
• This is frequently portrayed in a diagram called a phylogenetic tree.
• Phylogenies can be more complex than a bifurcating tree (e.g., lateral gene transfer, recombination, hybridization)
Whatever the History: Trying to Incorporate it is Critical
from Lake et al. doi: 10.1098/rstb.2009.0035
Phylogeny
• Applies to • Species• Genes• Genomes
Phylogeny: What is it good for?
Phylogeny: What is it good for?
Uses of Phylogenyin Genomics and Metagenomics
Uses of Phylogenyin Genomics and Metagenomics
Example 1:
Phylotyping
DNA extraction
PCRSequence
rRNA genes
Sequence alignment = Data matrixPhylogenetic tree
PCR
rRNA1
rRNA2
Makes lots of copies of the rRNA genes in sample
rRNA1 5’...ACACACATAGGTGGAGCTA
GCGATCGATCGA... 3’
E. coli
Humans
A
T
T
A
G
A
A
C
A
T
C
A
C
A
A
C
A
G
G
A
G
T
T
CrRNA1
E. coli Humans
rRNA2rRNA2
5’..TACAGTATAGGTGGAGCTAGCGACGATCGA... 3’
rRNA3 5’...ACGGCAAAATAGGTGGATT
CTAGCGATATAGA... 3’
rRNA4 5’...ACGGCCCGATAGGTGGATT
CTAGCGCCATAGA... 3’
rRNA3 C A C T G T
rRNA4 C A C A G T
Yeast T A C A G T
Yeast
rRNA3 rRNA4
rRNA Phylotyping
rRNA Phylotyping
• Collect DNA from environment
• PCR amplify rRNA genes using broad (so-called universal) primers
• Sequence• Align to others• Infer evolutionary tree• Unknowns “identified”
by placement on tree
Era IV: Genomes in Environment
shotgunsequence
Metagenomics
Venter et al., Science 304: 66. 2004
rRNA Phylotyping in Sargasso
RecA Phylotyping in Sargasso Data
Venter et al., Science 304: 66. 2004
0
0.125
0.250
0.375
0.500
Alphapro
teobacteria
Betap
roteobacteria
Gamm
aproteobacteria
Epsilo
nproteobacteria
Deltapro
teobacteria
Cyanobacteria
Firmicutes
Actinobacteria
Chlorobi
CFB
Chloroflexi
Spirochaetes
Fusobacteria
Deinococcus-Th
ermus
Euryarchaeota
Crenarchaeota
Sargasso Phylotypes
Wei
ghte
d %
of C
lone
s
Major Phylogenetic Group
EFG EFTu HSP70 RecA RpoB rRNA
Venter et al., Science 304: 66-74. 2004
Side benefit: binning
Metagenomics
Binning challenge
Binning challenge
Best binning method: reference genomes
Binning challenge
Best binning method: reference genomes
Binning challenge
No reference genome? What do you do?
Binning challenge
No reference genome? What do you do?
Composition, Assembly, others
Binning challenge
No reference genome? What do you do?
Phylogeny
Wu et al. 2006 PLoS Biology 4: e188.
Baumannia makes vitamins and cofactors
Sulcia makes amino acids
CFB Phyla
Side benefit II: PG Ecology
rRNA survey
• Sequence rRNAs
• Cluster
rRNA survey
• Sequence rRNAs
• Cluster• Identify
“OTUs”
OTU1OTU2OTU3OTU4OTU5OTU6OTU7OTU8OTU9OTU10
OTUs on Tree
OTU1OTU5
OTU4
OTU6
OTU8OTU9
OTU7OTU3OTU2
OTU10
OTUs on Tree
OTU1OTU5
OTU4
OTU6
OTU8OTU9
OTU7OTU3OTU2
OTU10
• Clades• Rates of
change• LGT• Convergence• Character
history
Unifrac
cally defined by a sequence similarity threshold) in the sampleas equally related. Newer ! diversity measures that incorporatephylogenetic information are more powerful because they ac-count for the degree of divergence between sequences (13, 18,29, 30). Phylogenetic ! diversity measures can also be eitherquantitative or qualitative depending on whether abundance istaken into account. The original, unweighted UniFrac measure(13) is a qualitative measure. Unweighted UniFrac measuresthe distance between two communities by calculating the frac-tion of the branch length in a phylogenetic tree that leads todescendants in either, but not both, of the two communities(Fig. 1A). The fixation index (FST), which measures thedistance between two communities by comparing the geneticdiversity within each community to the total genetic diversity ofthe communities combined (18), is a quantitative measure thataccounts for different levels of divergence between sequences.The phylogenetic test (P test), which measures the significanceof the association between environment and phylogeny (18), istypically used as a qualitative measure because duplicate se-quences are usually removed from the tree. However, the Ptest may be used in a semiquantitative manner if all clones,even those with identical or near-identical sequences, are in-cluded in the tree (13).
Here we describe a quantitative version of UniFrac that wecall “weighted UniFrac.” We show that weighted UniFrac be-haves similarly to the FST test in situations where both are
applicable. However, weighted UniFrac has a major advantageover FST because it can be used to combine data in whichdifferent parts of the 16S rRNA were sequenced (e.g., whennonoverlapping sequences can be combined into a single treeusing full-length sequences as guides). We use two differentdata sets to illustrate how analyses with quantitative and qual-itative ! diversity measures can lead to dramatically differentconclusions about the main factors that structure microbialdiversity. Specifically, qualitative measures that disregard rel-ative abundance can better detect effects of different foundingpopulations, such as the source of bacteria that first colonizethe gut of newborn mice and the effects of factors that arerestrictive for microbial growth such as temperature. In con-trast, quantitative measures that account for the relative abun-dance of microbial lineages can reveal the effects of moretransient factors such as nutrient availability.
MATERIALS AND METHODS
Weighted UniFrac. Weighted UniFrac is a new variant of the original un-weighted UniFrac measure that weights the branches of a phylogenetic treebased on the abundance of information (Fig. 1B). Weighted UniFrac is thus aquantitative measure of ! diversity that can detect changes in how many se-quences from each lineage are present, as well as detect changes in which taxaare present. This ability is important because the relative abundance of differentkinds of bacteria can be critical for describing community changes. In contrast,the original, unweighted UniFrac (Fig. 1A) is a qualitative ! diversity measurebecause duplicate sequences contribute no additional branch length to the tree(by definition, the branch length that separates a pair of duplicate sequences iszero, because no substitutions separate them).
The first step in applying weighted UniFrac is to calculate the raw weightedUniFrac value (u), according to the first equation:
u ! !i
n
bi " "Ai
AT#
Bi
BT"
Here, n is the total number of branches in the tree, bi is the length of branch i,Ai and Bi are the numbers of sequences that descend from branch i in commu-nities A and B, respectively, and AT and BT are the total numbers of sequencesin communities A and B, respectively. In order to control for unequal samplingeffort, Ai and Bi are divided by AT and BT.
If the phylogenetic tree is not ultrametric (i.e., if different sequences in thesample have evolved at different rates), clustering with weighted UniFrac willplace more emphasis on communities that contain quickly evolving taxa. Sincethese taxa are assigned more branch length, a comparison of the communitiesthat contain them will tend to produce higher values of u. In some situations, itmay be desirable to normalize u so that it has a value of 0 for identical commu-nities and 1 for nonoverlapping communities. This is accomplished by dividing uby a scaling factor (D), which is the average distance of each sequence from theroot, as shown in the equation as follows:
D ! !j
n
dj " #Aj
AT$
Bj
BT$
Here, dj is the distance of sequence j from the root, Aj and Bj are the numbersof times the sequences were observed in communities A and B, respectively, andAT and BT are the total numbers of sequences from communities A and B,respectively.
Clustering with normalized u values treats each sample equally instead of
TABLE 1. Measurements of diversity
Measure Measurement of " diversity Measurement of ! diversity
Only presence/absence of taxa considered Qualitative (species richness) QualitativeAdditionally accounts for the no. of times that
each taxon was observedQuantitative (species richness and evenness) Quantitative
FIG. 1. Calculation of the unweighted and the weighted UniFracmeasures. Squares and circles represent sequences from two differentenvironments. (a) In unweighted UniFrac, the distance between thecircle and square communities is calculated as the fraction of thebranch length that has descendants from either the square or the circleenvironment (black) but not both (gray). (b) In weighted UniFrac,branch lengths are weighted by the relative abundance of sequences inthe square and circle communities; square sequences are weightedtwice as much as circle sequences because there are twice as many totalcircle sequences in the data set. The width of branches is proportionalto the degree to which each branch is weighted in the calculations, andgray branches have no weight. Branches 1 and 2 have heavy weightssince the descendants are biased toward the square and circles, respec-tively. Branch 3 contributes no value since it has an equal contributionfrom circle and square sequences after normalization.
VOL. 73, 2007 PHYLOGENETICALLY COMPARING MICROBIAL COMMUNITIES 1577
Figure 1.Estimates of Phylogenetic Diversity (PD) and PD Gain (G) for the grey community. Theboxes represent taxa from the black, white, and grey communities. (A) PD is the sum of thebranches leading to the grey taxa. (B) G is the sum of the branches leading only to the greytaxa. (C) PD rarefaction curves showing the increase in branch length with sampling effortfor the intestinal and stool bacteria from three healthy individuals. Aligned16S rRNAsequences from the three individuals were available with the Supplementary Materials in(Eckburg, et al., 2005). The Arb parsimony insertion tool was used to add the sequences to atree containing over 9,000 sequences (Hugenholtz, 2002) that is available for download atthe rRNA Database Project II website (Maidak, et al., 2001). The curves represent theaverage values for 50 replicate trials.
Lozupone and Knight Page 24
FEMS Microbiol Rev. Author manuscript; available in PMC 2009 July 1.N
IH-P
A A
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NIH
-PA
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IH-P
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Caveat: Not Everything in Groups
GOS 1
GOS 2
GOS 3
GOS 4
GOS 5
RecA, RpoB in GOS
Wu et al PLoS One 2011
Uses of Phylogeny in Genomics and Metagenomics
Example 2:
Functional Diversity and Functional Predictions
Predicting Function
• Key step in genome projects• More accurate predictions help guide
experimental and computational analyses
• Many diverse approaches• All improved both by “phylogenomic”
type analyses that integrate evolutionary reconstructions and understanding of how new functions evolve
Predicting Function
• Identification of motifs– Short regions of sequence similarity that are indicative of
general activity– e.g., ATP binding
• Homology/similarity based methods– Gene sequence is searched against a databases of other
sequences– If significant similar genes are found, their functional
information is used• Problem
– Genes frequently have similarity to hundreds of motifs and multiple genes, not all with the same function
From Eisen et al. 1997 Nature Medicine 3: 1076-1078.
Blast Search of H. pylori “MutS”
• Blast search pulls up Syn. sp MutS#2 with much higher p value than other MutS homologs
• Based on this TIGR predicted this species had mismatch repair
• Assumes functional constancy
Based on Eisen et al. 1997 Nature Medicine 3: 1076-1078.
MutL??
Based on Eisen et al. 1997 Nature Medicine 3: 1076-1078.
Overlaying Functions onto Tree
Aquae Trepa
Rat
FlyXenla
MouseHumanYeast
NeucrArath
BorbuSynsp
Neigo
ThemaStrpy
Bacsu
Ecoli
TheaqDeiraChltr
SpombeYeast
YeastSpombe
MouseHuman
Arath
YeastHumanMouse
Arath
StrpyBacsu
HumanCeleg
YeastMetthBorbu
AquaeSynsp
Deira Helpy
mSaco
YeastCeleg
Human
MSH4
MSH5MutS2
MutS1
MSH1
MSH3
MSH6
MSH2
Based on Eisen, 1998 Nucl Acids Res 26: 4291-4300.
PHYLOGENENETIC PREDICTION OF GENE FUNCTION
IDENTIFY HOMOLOGS
OVERLAY KNOWNFUNCTIONS ONTO TREE
INFER LIKELY FUNCTIONOF GENE(S) OF INTEREST
1 2 3 4 5 6
3 5
3
1A 2A 3A 1B 2B 3B
2A 1B
1A
3A
1B2B
3B
ALIGN SEQUENCES
CALCULATE GENE TREE
12
4
6
CHOOSE GENE(S) OF INTEREST
2A
2A
5
3
Species 3Species 1 Species 2
1
1 2
2
2 31
1A 3A
1A 2A 3A
1A 2A 3A
4 6
4 5 6
4 5 6
2B 3B
1B 2B 3B
1B 2B 3B
ACTUAL EVOLUTION(ASSUMED TO BE UNKNOWN)
Duplication?
EXAMPLE A EXAMPLE B
Duplication?
Duplication?
Duplication
5
METHOD
Ambiguous
Based on Eisen, 1998 Genome Res 8: 163-167.
Based on Eisen, 1998 Genome Res 8: 163-167.
PHYLOGENENETIC PREDICTION OF GENE FUNCTION
IDENTIFY HOMOLOGS
OVERLAY KNOWNFUNCTIONS ONTO TREE
INFER LIKELY FUNCTIONOF GENE(S) OF INTEREST
1 2 3 4 5 6
3 5
3
1A 2A 3A 1B 2B 3B
2A 1B
1A
3A
1B2B
3B
ALIGN SEQUENCES
CALCULATE GENE TREE
12
4
6
CHOOSE GENE(S) OF INTEREST
2A
2A
5
3
Species 3Species 1 Species 2
1
1 2
2
2 31
1A 3A
1A 2A 3A
1A 2A 3A
4 6
4 5 6
4 5 6
2B 3B
1B 2B 3B
1B 2B 3B
ACTUAL EVOLUTION(ASSUMED TO BE UNKNOWN)
Duplication?
EXAMPLE A EXAMPLE B
Duplication?
Duplication?
Duplication
5
METHOD
Ambiguous
Diversity of Proteorhodopsins
Venter et al., 2004
Carboxydothermus sporulates
Wu et al. 2005 PLoS Genetics 1: e65.
Wu et al. 2005 PLoS Genetics 1: e65.
Uses of Phylogeny in Genomics and Metagenomics
Example 3:
Selecting Organisms for Study
Acidobacteria
Bacteroides
Fibrobacteres
Gemmimonas
Verrucomicrobia
Planctomycetes
Chloroflexi
Proteobacteria
Chlorobi
FirmicutesFusobacteria Actinobacteria
Cyanobacteria
Chlamydia
Spriochaetes
Deinococcus-Thermus
Aquificae
Thermotogae
TM6OS-K
Termite GroupOP8
Marine GroupAWS3
OP9
NKB19
OP3
OP10
TM7
OP1OP11
Nitrospira
SynergistesDeferribacteres
Thermudesulfobacteria
Chrysiogenetes
Thermomicrobia
Dictyoglomus
Coprothmermobacter
• At least 40 phyla of bacteria
As of 2002
Based on Hugenholtz, 2002
Acidobacteria
Bacteroides
Fibrobacteres
Gemmimonas
Verrucomicrobia
Planctomycetes
Chloroflexi
Proteobacteria
Chlorobi
FirmicutesFusobacteria Actinobacteria
Cyanobacteria
Chlamydia
Spriochaetes
Deinococcus-Thermus
Aquificae
Thermotogae
TM6OS-K
Termite GroupOP8
Marine GroupAWS3
OP9
NKB19
OP3
OP10
TM7
OP1OP11
Nitrospira
SynergistesDeferribacteres
Thermudesulfobacteria
Chrysiogenetes
Thermomicrobia
Dictyoglomus
Coprothmermobacter
• At least 40 phyla of bacteria
• Most genomes from three phyla
As of 2002
Based on Hugenholtz, 2002
Acidobacteria
Bacteroides
Fibrobacteres
Gemmimonas
Verrucomicrobia
Planctomycetes
Chloroflexi
Proteobacteria
Chlorobi
FirmicutesFusobacteria Actinobacteria
Cyanobacteria
Chlamydia
Spriochaetes
Deinococcus-Thermus
Aquificae
Thermotogae
TM6OS-K
Termite GroupOP8
Marine GroupAWS3
OP9
NKB19
OP3
OP10
TM7
OP1OP11
Nitrospira
SynergistesDeferribacteres
Thermudesulfobacteria
Chrysiogenetes
Thermomicrobia
Dictyoglomus
Coprothmermobacter
• At least 40 phyla of bacteria
• Most genomes from three phyla
• Some studies in other phyla
As of 2002
Based on Hugenholtz, 2002
Acidobacteria
Bacteroides
Fibrobacteres
Gemmimonas
Verrucomicrobia
Planctomycetes
Chloroflexi
Proteobacteria
Chlorobi
FirmicutesFusobacteria Actinobacteria
Cyanobacteria
Chlamydia
Spriochaetes
Deinococcus-Thermus
Aquificae
Thermotogae
TM6OS-K
Termite GroupOP8
Marine GroupAWS3
OP9
NKB19
OP3
OP10
TM7
OP1OP11
Nitrospira
SynergistesDeferribacteres
Thermudesulfobacteria
Chrysiogenetes
Thermomicrobia
Dictyoglomus
Coprothmermobacter
• At least 40 phyla of bacteria
• Most genomes from three phyla
• Some other phyla are only sparsely sampled
• Same trend in Eukaryotes
As of 2002
Based on Hugenholtz, 2002
Acidobacteria
Bacteroides
Fibrobacteres
Gemmimonas
Verrucomicrobia
Planctomycetes
Chloroflexi
Proteobacteria
Chlorobi
FirmicutesFusobacteria Actinobacteria
Cyanobacteria
Chlamydia
Spriochaetes
Deinococcus-Thermus
Aquificae
Thermotogae
TM6OS-K
Termite GroupOP8
Marine GroupAWS3
OP9
NKB19
OP3
OP10
TM7
OP1OP11
Nitrospira
SynergistesDeferribacteres
Thermudesulfobacteria
Chrysiogenetes
Thermomicrobia
Dictyoglomus
Coprothmermobacter
• At least 40 phyla of bacteria
• Most genomes from three phyla
• Some other phyla are only sparsely sampled
• Same trend in Viruses
As of 2002
Based on Hugenholtz, 2002
GEBA
http://www.jgi.doe.gov/programs/GEBA/pilot.html
GEBA: Components• Project overview (Phil Hugenholtz, Nikos Kyrpides, Jonathan
Eisen, Eddy Rubin, Jim Bristow)• Project management (David Bruce, Eileen Dalin, Lynne
Goodwin)• Culture collection and DNA prep (DSMZ, Hans-Peter Klenk)• Sequencing and closure (Eileen Dalin, Susan Lucas, Alla
Lapidus, Mat Nolan, Alex Copeland, Cliff Han, Feng Chen, Jan-Fang Cheng)
• Annotation and data release (Nikos Kyrpides, Victor Markowitz, et al)
• Analysis (Dongying Wu, Kostas Mavrommatis, Martin Wu, Victor Kunin, Neil Rawlings, Ian Paulsen, Patrick Chain, Patrik D’Haeseleer, Sean Hooper, Iain Anderson, Amrita Pati, Natalia N. Ivanova, Athanasios Lykidis, Adam Zemla)
• Adopt a microbe education project (Cheryl Kerfeld)• Outreach (David Gilbert)• $$$ (DOE, Eddy Rubin, Jim Bristow)
GEBA Now
• 300+ genomes• Rich sampling of major groups of
cultured organisms
GEBA Lesson 1:The rRNA Tree of Life is a Useful Tool
From Wu et al. 2009 Nature 462, 1056-1060
GEBA Lesson 2:The rRNA Tree of Life is not perfect ...
Badger et al. 2005 Int J System Evol Microbiol 55: 1021-1026.
16s WGT, 23S
GEBA Lesson 3: Phylogeny improves genome annotation
• Took 56 GEBA genomes and compared results vs. 56 randomly sampled new genomes
• Better definition of protein family sequence “patterns”• Greatly improves “comparative” and “evolutionary”
based predictions• Conversion of hypothetical into conserved hypotheticals• Linking distantly related members of protein families• Improved non-homology prediction
GEBA Lesson 4 :Metadata Important
GEBA Lesson 5:Improves discovering new genetic diversity
Phylogenetic Distribution Novelty: Bacterial Actin Related Protein
Haliangium ochraceum DSM 14365 Patrik D’haeseleer, Adam Zemla, Victor Kunin
A. cliftonii gi14269497U. pertusa gi50355609
C. boidinii gi57157304S. cerevisiae gi14318479L. starkeyi gi166080363 S. japonicus gi213407080
H. sapiens gi4501889M. cerebralis gi46326807
C. cinerea gi169844021N. crassa gi85101929I. scapularis gi215507378 H. sapiens gi5031569
S. japonicus gi213404844S. cerevisiae gi6320175D. melanogaster gi24642545G. gallus gi45382569C. neoformans gi58266690S. cerevisiae gi6322525D. melanogaster gi17737543H. sapiens gi5031573 H. ochraceum gi227395998
P. patens gi168051992 A. thaliana gi18394608
S. cerevisiae gi1008244
D. melanogaster gi17737347
D. hansenii gi218511921S. cerevisiae gi6323114
S. japonicus gi213408393 S. cerevisiae gi1301932
D. discoideum gi66802418
O. sativa gi182657420 A. thaliana gi1841 1737
D. melanogater gi19920358M. musculus gi226246593
99
67
100100
65
100
100
75
100
100
51
9973
10097
94100
74
100
87
100
0.5
ACTIN
ARP1
ARP2
ARP3
BARP
ARP4
ARP5
ARP6
ARP7
ARP10
See also Guljamow et al. 2007 Current Biology. Wu et al. 2009 Nature 462, 1056-1060
Protein Family Rarefaction
• Take data set of multiple complete genomes
• Identify all protein families using MCL• Plot # of genomes vs. # of protein families
Wu et al. 2009 Nature 462, 1056-1060
Wu et al. 2009 Nature 462, 1056-1060
Wu et al. 2009 Nature 462, 1056-1060
Wu et al. 2009 Nature 462, 1056-1060
Wu et al. 2009 Nature 462, 1056-1060
Synapomorphies exist
Wu et al. 2009 Nature 462, 1056-1060
GEBA Lesson 6:Improves Analysis of Uncultured
0
0.125
0.250
0.375
0.500
Alphapro
teobacteria
Betap
roteobacteria
Gamm
aproteobacteria
Epsilo
nproteobacteria
Deltapro
teobacteria
Cyanobacteria
Firmicutes
Actinobacteria
Chlorobi
CFB
Chloroflexi
Spirochaetes
Fusobacteria
Deinococcus-Th
ermus
Euryarchaeota
Crenarchaeota
Sargasso Phylotypes
Wei
ghte
d %
of C
lone
s
Major Phylogenetic Group
EFGEFTuHSP70RecARpoBrRNA
Metagenomic Phylotyping
GEBA Project improves metagenomic analysis
Venter et al., Science 304: 66-74. 2004
0
0.125
0.250
0.375
0.500
Alphapro
teobacteria
Betap
roteobacteria
Gamm
aproteobacteria
Epsilo
nproteobacteria
Deltapro
teobacteria
Cyanobacteria
Firmicutes
Actinobacteria
Chlorobi
CFB
Chloroflexi
Spirochaetes
Fusobacteria
Deinococcus-Th
ermus
Euryarchaeota
Crenarchaeota
Sargasso Phylotypes
Wei
ghte
d %
of C
lone
s
Major Phylogenetic Group
EFGEFTuHSP70RecARpoBrRNA
But not a lot
Venter et al., Science 304: 66-74. 2004
Metagenomic Phylotyping
• AND THEN ALL OF THEM WERE DECEIVED
• For each of these areas - need to do a MUCH better job ...
Improving Phylotyping
Major Issues in Phylotpying
Beyond Moore’s Law Metagenomics
Short reads
Beyond Moore’s Law Metagenomics
Short reads
WE NEED NEW METHODS
Major Issues in Phylotpying
Method 1: Each is an island
• Each new sequences is an island
• Take reference data• Build alignment, models, trees• Add new sequence to reference alignment
and build tree
STAP
STAP database, and the query sequence is aligned to them usingthe CLUSTALW profile alignment algorithm [40] as describedabove for domain assignment. By adapting the profile alignment
algorithm, the alignments from the STAP database remain intact,while gaps are inserted and nucleotides are trimmed for the querysequence according to the profile defined by the previousalignments from the databases. Thus the accuracy and quality ofthe alignment generated at this step depends heavily on the qualityof the Bacterial/Archaeal ss-rRNA alignments from theGreengenes project or the Eukaryotic ss-rRNA alignments fromthe RDPII project.
Phylogenetic analysis using multiple sequence alignments rests onthe assumption that the residues (nucleotides or amino acids) at thesame position in every sequence in the alignment are homologous.Thus, columns in the alignment for which ‘‘positional homology’’cannot be robustly determined must be excluded from subsequentanalyses. This process of evaluating homology and eliminatingquestionable columns, known as masking, typically requires time-consuming, skillful, human intervention. We designed an automat-ed masking method for ss-rRNA alignments, thus eliminating thisbottleneck in high-throughput processing.
First, an alignment score is calculated for each aligned columnby a method similar to that used in the CLUSTALX package [42].Specifically, an R-dimensional sequence space representing all thepossible nucleotide character states is defined. Then for eachaligned column, the nucleotide populating that column in each ofthe aligned sequences is assigned a score in each of the Rdimensions (Sr) according to the IUB matrix [42]. The consensus‘‘nucleotide’’ for each column (X) also has R dimensions, with thescore for each dimension (Xr) calculated as the average of thescores for that column in that dimension (average of Sr). Thus thescore of the consensus nucleotide is a mathematical expressiondescribing the average ‘‘nucleotide’’ in that column for thatalignment.
Figure 2. Domain assignment. In Step 1, STAP assigns a domain toeach query sequence based on its position in a maximum likelihoodtree of representative ss-rRNA sequences. Because the tree illustratedhere is not rooted, domain assignment would not be accurate andreliable (sequence similarity based methods cannot make an accurateassignment in this case either). However the figure illustrates animportant role of the tree-based domain assignment step, namelyautomatic identification of deep-branching environmental ss-rRNAs.doi:10.1371/journal.pone.0002566.g002
Figure 1. A flow chart of the STAP pipeline.doi:10.1371/journal.pone.0002566.g001
ss-rRNA Taxonomy Pipeline
PLoS ONE | www.plosone.org 5 July 2008 | Volume 3 | Issue 7 | e2566
Wu et al. 2008 PLoS One
STAP database, and the query sequence is aligned to them usingthe CLUSTALW profile alignment algorithm [40] as describedabove for domain assignment. By adapting the profile alignment
algorithm, the alignments from the STAP database remain intact,while gaps are inserted and nucleotides are trimmed for the querysequence according to the profile defined by the previousalignments from the databases. Thus the accuracy and quality ofthe alignment generated at this step depends heavily on the qualityof the Bacterial/Archaeal ss-rRNA alignments from theGreengenes project or the Eukaryotic ss-rRNA alignments fromthe RDPII project.
Phylogenetic analysis using multiple sequence alignments rests onthe assumption that the residues (nucleotides or amino acids) at thesame position in every sequence in the alignment are homologous.Thus, columns in the alignment for which ‘‘positional homology’’cannot be robustly determined must be excluded from subsequentanalyses. This process of evaluating homology and eliminatingquestionable columns, known as masking, typically requires time-consuming, skillful, human intervention. We designed an automat-ed masking method for ss-rRNA alignments, thus eliminating thisbottleneck in high-throughput processing.
First, an alignment score is calculated for each aligned columnby a method similar to that used in the CLUSTALX package [42].Specifically, an R-dimensional sequence space representing all thepossible nucleotide character states is defined. Then for eachaligned column, the nucleotide populating that column in each ofthe aligned sequences is assigned a score in each of the Rdimensions (Sr) according to the IUB matrix [42]. The consensus‘‘nucleotide’’ for each column (X) also has R dimensions, with thescore for each dimension (Xr) calculated as the average of thescores for that column in that dimension (average of Sr). Thus thescore of the consensus nucleotide is a mathematical expressiondescribing the average ‘‘nucleotide’’ in that column for thatalignment.
Figure 2. Domain assignment. In Step 1, STAP assigns a domain toeach query sequence based on its position in a maximum likelihoodtree of representative ss-rRNA sequences. Because the tree illustratedhere is not rooted, domain assignment would not be accurate andreliable (sequence similarity based methods cannot make an accurateassignment in this case either). However the figure illustrates animportant role of the tree-based domain assignment step, namelyautomatic identification of deep-branching environmental ss-rRNAs.doi:10.1371/journal.pone.0002566.g002
Figure 1. A flow chart of the STAP pipeline.doi:10.1371/journal.pone.0002566.g001
ss-rRNA Taxonomy Pipeline
PLoS ONE | www.plosone.org 5 July 2008 | Volume 3 | Issue 7 | e2566
Each sequence analyzed separately
AMPHORA
Guide tree
Wu and Eisen Genome Biology 2008 9:R151 doi:10.1186/gb-2008-9-10-r151
Phylotyping w/ Proteins
Wu and Eisen Genome Biology 2008 9:R151 doi:10.1186/gb-2008-9-10-r151
Whole Genome Tree
Wu and Eisen Genome Biology 2008 9:R151 doi:10.1186/gb-2008-9-10-r151
Method 2: Most in the Family
Phylogenetic Challenge
A single tree with everything?
xxxxxxxxxxxxxxxxxxxxxxx
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A single tree with everything(as long as there is a lot of overlap)
Phylogenetic Challenge
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A single tree with everything(as long as there is a lot of overlap)
Phylogenetic Challenge
A single tree with everything?
Phylogenetic Challenge
Venter et al., Science 304: 66. 2004
rRNA in Sargasso Metagenome
STAP All
STAP database, and the query sequence is aligned to them usingthe CLUSTALW profile alignment algorithm [40] as describedabove for domain assignment. By adapting the profile alignment
algorithm, the alignments from the STAP database remain intact,while gaps are inserted and nucleotides are trimmed for the querysequence according to the profile defined by the previousalignments from the databases. Thus the accuracy and quality ofthe alignment generated at this step depends heavily on the qualityof the Bacterial/Archaeal ss-rRNA alignments from theGreengenes project or the Eukaryotic ss-rRNA alignments fromthe RDPII project.
Phylogenetic analysis using multiple sequence alignments rests onthe assumption that the residues (nucleotides or amino acids) at thesame position in every sequence in the alignment are homologous.Thus, columns in the alignment for which ‘‘positional homology’’cannot be robustly determined must be excluded from subsequentanalyses. This process of evaluating homology and eliminatingquestionable columns, known as masking, typically requires time-consuming, skillful, human intervention. We designed an automat-ed masking method for ss-rRNA alignments, thus eliminating thisbottleneck in high-throughput processing.
First, an alignment score is calculated for each aligned columnby a method similar to that used in the CLUSTALX package [42].Specifically, an R-dimensional sequence space representing all thepossible nucleotide character states is defined. Then for eachaligned column, the nucleotide populating that column in each ofthe aligned sequences is assigned a score in each of the Rdimensions (Sr) according to the IUB matrix [42]. The consensus‘‘nucleotide’’ for each column (X) also has R dimensions, with thescore for each dimension (Xr) calculated as the average of thescores for that column in that dimension (average of Sr). Thus thescore of the consensus nucleotide is a mathematical expressiondescribing the average ‘‘nucleotide’’ in that column for thatalignment.
Figure 2. Domain assignment. In Step 1, STAP assigns a domain toeach query sequence based on its position in a maximum likelihoodtree of representative ss-rRNA sequences. Because the tree illustratedhere is not rooted, domain assignment would not be accurate andreliable (sequence similarity based methods cannot make an accurateassignment in this case either). However the figure illustrates animportant role of the tree-based domain assignment step, namelyautomatic identification of deep-branching environmental ss-rRNAs.doi:10.1371/journal.pone.0002566.g002
Figure 1. A flow chart of the STAP pipeline.doi:10.1371/journal.pone.0002566.g001
ss-rRNA Taxonomy Pipeline
PLoS ONE | www.plosone.org 5 July 2008 | Volume 3 | Issue 7 | e2566
Combine all into one alignment
Venter et al., Science 304: 66. 2004
RecA in Sargasso
0
0.125
0.250
0.375
0.500
Alphapro
teobacteria
Betap
roteobacteria
Gamm
aproteobacteria
Epsilo
nproteobacteria
Deltapro
teobacteria
Cyanobacteria
Firmicutes
Actinobacteria
Chlorobi
CFB
Chloroflexi
Spirochaetes
Fusobacteria
Deinococcus-Th
ermus
Euryarchaeota
Crenarchaeota
Sargasso Phylotypes
Wei
ghte
d %
of C
lone
s
Major Phylogenetic Group
EFG EFTu HSP70 RecA RpoB rRNA
Venter et al., Science 304: 66-74. 2004
Protein vs. rRNA Sargasso Data
Kembel Correction
Method 3: All in the family
• Combine new sequences into one tree
• Take reference data• Build alignment, models, trees• Add all sequences to reference alignment
and build tree
A single tree with everything?
Phylogenetic Challenge
A single tree with everything?
Phylogenetic Challenge
alignment used to build the profile, resulting in a multiplesequence alignment of full-length reference sequences andmetagenomic reads. The final step of the alignment process is aquality control filter that 1) ensures that only homologous SSU-rRNA sequences from the appropriate phylogenetic domain areincluded in the final alignment, and 2) masks highly gappedalignment columns (see Text S1).We use this high quality alignment of metagenomic reads and
references sequences to construct a fully-resolved, phylogenetictree and hence determine the evolutionary relationships betweenthe reads. Reference sequences are included in this stage of theanalysis to guide the phylogenetic assignment of the relativelyshort metagenomic reads. While the software can be easilyextended to incorporate a number of different phylogenetic toolscapable of analyzing metagenomic data (e.g., RAxML [27],pplacer [28], etc.), PhylOTU currently employs FastTree as adefault method due to its relatively high speed-to-performanceratio and its ability to construct accurate trees in the presence ofhighly-gapped data [29]. After construction of the phylogeny,lineages representing reference sequences are pruned from thetree. The resulting phylogeny of metagenomic reads is then used tocompute a PD distance matrix in which the distance between apair of reads is defined as the total tree path distance (i.e., branchlength) separating the two reads [30]. This tree-based distancematrix is subsequently used to hierarchically cluster metagenomicreads via MOTHUR into OTUs in a fashion similar to traditionalPID-based analysis [31]. As with PID clustering, the hierarchicalalgorithm can be tuned to produce finer or courser clusters,corresponding to different taxonomic levels, by adjusting theclustering threshold and linkage method.To evaluate the performance of PhylOTU, we employed
statistical comparisons of distance matrices and clustering resultsfor a variety of data sets. These investigations aimed 1) to compare
PD versus PID clustering, 2) to explore overlap between PhylOTUclusters and recognized taxonomic designations, and 3) to quantifythe accuracy of PhylOTU clusters from shotgun reads relative tothose obtained from full-length sequences.
PhylOTU Clusters Recapitulate PID ClustersWe sought to identify how PD-based clustering compares to
commonly employed PID-based clustering methods by applyingthe two methods to the same set of sequences. Both PID-basedclustering and PhylOTU may be used to identify OTUs fromoverlapping sequences. Therefore we applied both methods to adataset of 508 full-length bacterial SSU-rRNA sequences (refer-ence sequences; see above) obtained from the Ribosomal DatabaseProject (RDP) [25]. Recent work has demonstrated that PID ismore accurately calculated from pairwise alignments than multiplesequence alignments [32–33], so we used ESPRIT, whichimplements pairwise alignments, to obtain a PID distance matrixfor the reference sequences [32]. We used PhylOTU to compute aPD distance matrix for the same data. Then, we used MOTHUR tohierarchically cluster sequences into OTUs based on both PIDand PD. For each of the two distance matrices, we employed arange of clustering thresholds and three different definitions oflinkage in the hierarchical clustering algorithm: nearest-neighbor,average, and furthest-neighbor.To statistically evaluate the similarity of cluster composition
between of each pair of clustering results, we used two summarystatistics that together capture the frequency with which sequencesare co-clustered in both analyses: true conjunction rate (i.e., theproportion of pairs of sequences derived from the same cluster inthe first analysis that also are clustered together in the secondanalysis) and true disjunction rate (i.e., the proportion of pairs ofsequences derived from different clusters in the first analysis thatalso are not clustered together in the second analysis) (see Methods
Figure 1. PhylOTU Workflow. Computational processes are represented as squares and databases are represented as cylinders in this generalizeworkflow of PhylOTU. See Results section for details.doi:10.1371/journal.pcbi.1001061.g001
Finding Metagenomic OTUs
PLoS Computational Biology | www.ploscompbiol.org 3 January 2011 | Volume 7 | Issue 1 | e1001061
PhylOTU - Sharpton et al. PLoS Comp. Bio 2011
PhylOTU
Phylosift/ pplacer
Method 4: All in the genome
• Combine new sequences from different gene families into one tree
• Take reference data• Build alignment, models• Concatenate• Add all sequences to reference alignment
and build tree
Challenge
• Each gene poorly sampled in metagenomes
• Can we combine all into a single tree?
Kembel et al. The phylogenetic diversity of metagenomes. PLoS One 2011
Kembel Combiner
Kembel Combiner
cally defined by a sequence similarity threshold) in the sampleas equally related. Newer ! diversity measures that incorporatephylogenetic information are more powerful because they ac-count for the degree of divergence between sequences (13, 18,29, 30). Phylogenetic ! diversity measures can also be eitherquantitative or qualitative depending on whether abundance istaken into account. The original, unweighted UniFrac measure(13) is a qualitative measure. Unweighted UniFrac measuresthe distance between two communities by calculating the frac-tion of the branch length in a phylogenetic tree that leads todescendants in either, but not both, of the two communities(Fig. 1A). The fixation index (FST), which measures thedistance between two communities by comparing the geneticdiversity within each community to the total genetic diversity ofthe communities combined (18), is a quantitative measure thataccounts for different levels of divergence between sequences.The phylogenetic test (P test), which measures the significanceof the association between environment and phylogeny (18), istypically used as a qualitative measure because duplicate se-quences are usually removed from the tree. However, the Ptest may be used in a semiquantitative manner if all clones,even those with identical or near-identical sequences, are in-cluded in the tree (13).
Here we describe a quantitative version of UniFrac that wecall “weighted UniFrac.” We show that weighted UniFrac be-haves similarly to the FST test in situations where both are
applicable. However, weighted UniFrac has a major advantageover FST because it can be used to combine data in whichdifferent parts of the 16S rRNA were sequenced (e.g., whennonoverlapping sequences can be combined into a single treeusing full-length sequences as guides). We use two differentdata sets to illustrate how analyses with quantitative and qual-itative ! diversity measures can lead to dramatically differentconclusions about the main factors that structure microbialdiversity. Specifically, qualitative measures that disregard rel-ative abundance can better detect effects of different foundingpopulations, such as the source of bacteria that first colonizethe gut of newborn mice and the effects of factors that arerestrictive for microbial growth such as temperature. In con-trast, quantitative measures that account for the relative abun-dance of microbial lineages can reveal the effects of moretransient factors such as nutrient availability.
MATERIALS AND METHODS
Weighted UniFrac. Weighted UniFrac is a new variant of the original un-weighted UniFrac measure that weights the branches of a phylogenetic treebased on the abundance of information (Fig. 1B). Weighted UniFrac is thus aquantitative measure of ! diversity that can detect changes in how many se-quences from each lineage are present, as well as detect changes in which taxaare present. This ability is important because the relative abundance of differentkinds of bacteria can be critical for describing community changes. In contrast,the original, unweighted UniFrac (Fig. 1A) is a qualitative ! diversity measurebecause duplicate sequences contribute no additional branch length to the tree(by definition, the branch length that separates a pair of duplicate sequences iszero, because no substitutions separate them).
The first step in applying weighted UniFrac is to calculate the raw weightedUniFrac value (u), according to the first equation:
u ! !i
n
bi " "Ai
AT#
Bi
BT"
Here, n is the total number of branches in the tree, bi is the length of branch i,Ai and Bi are the numbers of sequences that descend from branch i in commu-nities A and B, respectively, and AT and BT are the total numbers of sequencesin communities A and B, respectively. In order to control for unequal samplingeffort, Ai and Bi are divided by AT and BT.
If the phylogenetic tree is not ultrametric (i.e., if different sequences in thesample have evolved at different rates), clustering with weighted UniFrac willplace more emphasis on communities that contain quickly evolving taxa. Sincethese taxa are assigned more branch length, a comparison of the communitiesthat contain them will tend to produce higher values of u. In some situations, itmay be desirable to normalize u so that it has a value of 0 for identical commu-nities and 1 for nonoverlapping communities. This is accomplished by dividing uby a scaling factor (D), which is the average distance of each sequence from theroot, as shown in the equation as follows:
D ! !j
n
dj " #Aj
AT$
Bj
BT$
Here, dj is the distance of sequence j from the root, Aj and Bj are the numbersof times the sequences were observed in communities A and B, respectively, andAT and BT are the total numbers of sequences from communities A and B,respectively.
Clustering with normalized u values treats each sample equally instead of
TABLE 1. Measurements of diversity
Measure Measurement of " diversity Measurement of ! diversity
Only presence/absence of taxa considered Qualitative (species richness) QualitativeAdditionally accounts for the no. of times that
each taxon was observedQuantitative (species richness and evenness) Quantitative
FIG. 1. Calculation of the unweighted and the weighted UniFracmeasures. Squares and circles represent sequences from two differentenvironments. (a) In unweighted UniFrac, the distance between thecircle and square communities is calculated as the fraction of thebranch length that has descendants from either the square or the circleenvironment (black) but not both (gray). (b) In weighted UniFrac,branch lengths are weighted by the relative abundance of sequences inthe square and circle communities; square sequences are weightedtwice as much as circle sequences because there are twice as many totalcircle sequences in the data set. The width of branches is proportionalto the degree to which each branch is weighted in the calculations, andgray branches have no weight. Branches 1 and 2 have heavy weightssince the descendants are biased toward the square and circles, respec-tively. Branch 3 contributes no value since it has an equal contributionfrom circle and square sequences after normalization.
VOL. 73, 2007 PHYLOGENETICALLY COMPARING MICROBIAL COMMUNITIES 1577
Improving Phylotyping II
• We need to analyze more gene families
Families/PD not uniform
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Phylogenetic group Genome Number
Gene Number
Maker Candidates
Archaea 62 145415 106Actinobacteria 63 267783 136Alphaproteobacteria 94 347287 121Betaproteobacteria 56 266362 311Gammaproteobacteria
126 483632 118Deltaproteobacteria 25 102115 206Epislonproteobacteria
18 33416 455Bacteriodes 25 71531 286Chlamydae 13 13823 560Chloroflexi 10 33577 323Cyanobacteria 36 124080 590Firmicutes 106 312309 87Spirochaetes 18 38832 176Thermi 5 14160 974Thermotogae 9 17037 684
Improving Functional Predictions
Improving Functional Predictions
• We need to analyze even more gene families
Sifting FamiliesRepresentative
Genomes
ExtractProtein
Annotation
All v. AllBLAST
HomologyClustering
(MCL)
SFams
Align & Build
HMMs
HMMs
Screen forHomologs
NewGenomes
ExtractProtein
Annotation
Figure 1
Sharpton et al. submitted
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Sharpton et al. submitted
Phylogenetic Contrasts
NMF in MetagenomesCharacterizing the niche-space distributions of components
Sit
es
N orth American E ast C oast_G S 005_E mbayment
N orth American E ast C oast_G S 002_C oasta l
N orth American E ast C oast_G S 003_C oasta l
N orth American E ast C oast_G S 007_C oasta l
N orth American E ast C oast_G S 004_C oasta l
N orth American E ast C oast_G S 013_C oasta l
N orth American E ast C oast_G S 008_C oasta l
N orth American E ast C oast_G S 011_E stuary
N orth American E ast C oast_G S 009_C oasta l
E astern Tropica l Pacific_G S 021_C oasta l
N orth American E ast C oast_G S 006_E stuary
N orth American E ast C oast_G S 014_C oasta l
Polynesia Archipelagos_G S 051_C ora l R eef Atoll
G alapagos Islands_G S 036_C oasta l
G alapagos Islands_G S 028_C oasta l
Indian O cean_G S 117a_C oasta l sample
G alapagos Islands_G S 031_C oasta l upwelling
G alapagos Islands_G S 029_C oasta l
G alapagos Islands_G S 030_W arm S eep
G alapagos Islands_G S 035_C oasta l
S argasso S ea_G S 001c_O pen O cean
E astern Tropica l Pacific_G S 022_O pen O cean
G alapagos Islands_G S 027_C oasta l
Indian O cean_G S 149_H arbor
Indian O cean_G S 123_O pen O cean
C aribbean S ea_G S 016_C oasta l S ea
Indian O cean_G S 148_Fringing R eef
Indian O cean_G S 113_O pen O cean
Indian O cean_G S 112a_O pen O cean
C aribbean S ea_G S 017_O pen O cean
Indian O cean_G S 121_O pen O cean
Indian O cean_G S 122a_O pen O cean
G alapagos Islands_G S 034_C oasta l
C aribbean S ea_G S 018_O pen O cean
Indian O cean_G S 108a_Lagoon R eef
Indian O cean_G S 110a_O pen O cean
E astern Tropica l Pacific_G S 023_O pen O cean
Indian O cean_G S 114_O pen O cean
C aribbean S ea_G S 019_C oasta l
C aribbean S ea_G S 015_C oasta l
Indian O cean_G S 119_O pen O cean
G alapagos Islands_G S 026_O pen O cean
Polynesia Archipelagos_G S 049_C oasta l
Indian O cean_G S 120_O pen O cean
Polynesia Archipelagos_G S 048a_C ora l R eef
Component 1
Component 2
Component 3
Component 4
Component 5
0 .1 0 .2 0 .3 0 .4 0 .5 0 .6
0 .2 0 .4 0 .6 0 .8 1 .0
Salin
ity
Sam
ple
Dep
th
Ch
loro
ph
yll
Tem
pera
ture
Inso
lati
on
Wate
r D
ep
th
G enera l
H ighM ediumLowN A
H ighM ediumLowN A
W ater depth
>4000m2000!4000m900!2000m100!200m20!100m0!20m
>4000m2000!4000m900!2000m100!200m20!100m0!20m
(a) (b) (c)
Figure 3: a) Niche-space distributions for our five components (HT ); b) the site-similarity matrix (HT H); c) environmental variables for the sites. The matrices arealigned so that the same row corresponds to the same site in each matrix. Sites areordered by applying spectral reordering to the similarity matrix (see Materials andMethods). Rows are aligned across the three matrices.
Figure 3a shows the estimated niche-space distribution for each of the five com-ponents. Components 2 (Photosystem) and 4 (Unidentified) are broadly distributed;Components 1 (Signalling) and 5 (Unidentified) are largely restricted to a handful ofsites; and component 3 shows an intermediate pattern. There is a great deal of overlapbetween niche-space distributions for di�erent components.
Figure 3b shows the pattern of filtered similarity between sites. We see clear pat-terns of grouping, that do not emerge when we calculate functional distances withoutfiltering, or using PCA rather than NMF filtering (Figure 3 in Text S1). As withthe Pfams, we see clusters roughly associated with our components, but there is moreoverlapping than with the Pfam clusters (Figure 2b).
Figure 3c shows the distribution of environmental variables measured at each site.Inspection of Figure 3 reveals qualitative correspondence between environmental factorsand clusters of similar sites in the similarity matrix. For example, the “North AmericanEast Coast” samples are divided into two groups, one in the top left and the other in thebottom right of the similarity matrix. Inspection of the environmental features suggeststhat the split in these samples could be mostly due to the di�erences in insolation andwater depth.
We can also examine patterns of similarity between the components themselves,using niche-site distributions or functional profiles (see Figure 5 in Text S1). All 5
8
Non-negative matrix factorizationJiang et al. submitted
w/ Weitz, Dushoff, Langille, Neches, Levin, etc
Better Genome Phylogenies
IV: Better Reference Tree
Morgan et al. submitted
Most Important Issue
We have still only scratched the surface of microbial diversity
rRNA Tree of Life
Figure from Barton, Eisen et al. “Evolution”, CSHL Press. 2007.
Based on tree from Pace 1997 Science 276:734-740
Archaea
Eukaryotes
Bacteria
PD: Genomes
From Wu et al. 2009 Nature 462, 1056-1060
From Wu et al. 2009 Nature 462, 1056-1060
PD: Genomes + GEBA
PD: Isolates
From Wu et al. 2009 Nature 462, 1056-1060
0.01
Legend:
Dataset genes
MA ammonialyase
MA mutase S subunit
MA mutase E subunit
PHA synthatase
cellulase
CRISPRs
CAS
Color ranges:
New Genomes
Haloferax mediterraneiHaloferax mucosumHaloferax volcaniiHaloferax sulfurifontisHaloferax denitrificans
Halogeometricum borinquenseHaloquadratum walsbyiHalorubrum lacusprofundi
Halalkalicoccus jeotgali
Natrialba magadiiHaloterrigena turkmenica
Halopiger xanaduensis
Haloarcula vallismortisHaloarcula marismortuiHaloarcula sinaiiensisHaloarcula californiae
Halomicrobium mukohataeiHalorhabdus utahensisNatronomonas pharaonis
Halobacterium sp. NRC�1Halobacterium salinarum R1
0.320.93
0.551
0.83
0.900.34
0.32
0.411
0.52
0.080.23
0.790.52
10.710.24
1
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##
Figure 8. Independent expansion of the TATA-binding protein family in two haloarchaeal genera. Phylogeny of TATA-binding protein (TBP) homologs identified by RAST with Bootstrap values shown. Colored branches represent duplication events (with the dark blue branch representing four duplications). Ancestral TBP (found in all genomes) is shown on the purple branch. Successive duplications are shown in darkening shades of green (Halobacterium) or blue (Haloferax). Lynch et al. in preparation
PD: All
From Wu et al. 2009 Nature 462, 1056-1060
Uncultured Lineages:
• Get into culture• Enrichment cultures• If abundant in low diversity ecosystems• Flow sorting• Microbeads• Microfluidic sorting• Single cell amplification
120
Number of SAGs from Candidate Phyla
OD
1
OP
11
OP
3
SA
R4
06
Site A: Hydrothermal vent 4 1 - -Site B: Gold Mine 6 13 2 -Site C: Tropical gyres (Mesopelagic) - - - 2Site D: Tropical gyres (Photic zone) 1 - - -
Sample collections at 4 additional sites are underway.
Phil Hugenholtz
GEBA uncultured
Phylogenomics Future 3
Need Experiments from Across the Tree of Life too
Acidobacteria
Bacteroides
Fibrobacteres
Gemmimonas
Verrucomicrobia
Planctomycetes
Chloroflexi
Proteobacteria
Chlorobi
FirmicutesFusobacteria Actinobacteria
Cyanobacteria
Chlamydia
Spriochaetes
Deinococcus-Thermus
Aquificae
Thermotogae
TM6OS-K
Termite GroupOP8
Marine GroupAWS3
OP9
NKB19
OP3
OP10
TM7
OP1OP11
Nitrospira
SynergistesDeferribacteres
Thermudesulfobacteria
Chrysiogenetes
Thermomicrobia
Dictyoglomus
Coprothmermobacter
• At least 40 phyla of bacteria
As of 2002
Based on Hugenholtz, 2002
Acidobacteria
Bacteroides
Fibrobacteres
Gemmimonas
Verrucomicrobia
Planctomycetes
Chloroflexi
Proteobacteria
Chlorobi
FirmicutesFusobacteria Actinobacteria
Cyanobacteria
Chlamydia
Spriochaetes
Deinococcus-Thermus
Aquificae
Thermotogae
TM6OS-K
Termite GroupOP8
Marine GroupAWS3
OP9
NKB19
OP3
OP10
TM7
OP1OP11
Nitrospira
SynergistesDeferribacteres
Thermudesulfobacteria
Chrysiogenetes
Thermomicrobia
Dictyoglomus
Coprothmermobacter
• At least 40 phyla of bacteria
• Experimental studies are mostly from three phyla
As of 2002
Based on Hugenholtz, 2002
Acidobacteria
Bacteroides
Fibrobacteres
Gemmimonas
Verrucomicrobia
Planctomycetes
Chloroflexi
Proteobacteria
Chlorobi
FirmicutesFusobacteria Actinobacteria
Cyanobacteria
Chlamydia
Spriochaetes
Deinococcus-Thermus
Aquificae
Thermotogae
TM6OS-K
Termite GroupOP8
Marine GroupAWS3
OP9
NKB19
OP3
OP10
TM7
OP1OP11
Nitrospira
SynergistesDeferribacteres
Thermudesulfobacteria
Chrysiogenetes
Thermomicrobia
Dictyoglomus
Coprothmermobacter
• At least 40 phyla of bacteria
• Experimental studies are mostly from three phyla
• Some studies in other phyla
As of 2002
Based on Hugenholtz, 2002
Acidobacteria
Bacteroides
Fibrobacteres
Gemmimonas
Verrucomicrobia
Planctomycetes
Chloroflexi
Proteobacteria
Chlorobi
FirmicutesFusobacteria Actinobacteria
Cyanobacteria
Chlamydia
Spriochaetes
Deinococcus-Thermus
Aquificae
Thermotogae
TM6OS-K
Termite GroupOP8
Marine GroupAWS3
OP9
NKB19
OP3
OP10
TM7
OP1OP11
Nitrospira
SynergistesDeferribacteres
Thermudesulfobacteria
Chrysiogenetes
Thermomicrobia
Dictyoglomus
Coprothmermobacter
• At least 40 phyla of bacteria
• Experimental studies are mostly from three phyla
• Some studies in other phyla
• Same trend in Eukaryotes
As of 2002
Based on Hugenholtz, 2002
0.1
Acidobacteria
Bacteroides
Fibrobacteres
Gemmimonas
Verrucomicrobia
Planctomycetes
Chloroflexi
Proteobacteria
Chlorobi
FirmicutesFusobacteria Actinobacteria
Cyanobacteria
Chlamydia
Spriochaetes
Deinococcus-Thermus
Aquificae
Thermotogae
TM6OS-K
Termite GroupOP8
Marine GroupAWS3
OP9
NKB19
OP3
OP10
TM7
OP1OP11
Nitrospira
SynergistesDeferribacteres
Thermudesulfobacteria
Chrysiogenetes
Thermomicrobia
Dictyoglomus
Coprothmermobacter
Tree based on Hugenholtz (2002) with some modifications.
Need experimental studies from across the tree too
0.1
Acidobacteria
Bacteroides
Fibrobacteres
Gemmimonas
Verrucomicrobia
Planctomycetes
Chloroflexi
Proteobacteria
Chlorobi
FirmicutesFusobacteria Actinobacteria
Cyanobacteria
Chlamydia
Spriochaetes
Deinococcus-Thermus
Aquificae
Thermotogae
TM6OS-K
Termite GroupOP8
Marine GroupAWS3
OP9
NKB19
OP3
OP10
TM7
OP1OP11
Nitrospira
SynergistesDeferribacteres
Thermudesulfobacteria
Chrysiogenetes
Thermomicrobia
Dictyoglomus
Coprothmermobacter
Tree based on Hugenholtz (2002) with some modifications.
Adopt a Microbe
A Happy Tree of Life
Acknowledgements
• $$$• DOE• NSF• GBMF• Sloan• DARPA• DSMZ• DHS
• People, places• DOE JGI: Eddy Rubin, Phil Hugenholtz, Nikos Kyrpides• UC Davis: Aaron Darling, Dongying Wu, Holly Bik, Russell
Neches, Jenna Morgan-Lang• Other: Jessica Green, Katie Pollard, Martin Wu, Tom Slezak,
Jack Gilbert, Steven Kembel, J. Craig Venter, Naomi Ward, Hans-Peter Klenk
iSEEM Project