An expanded genomic representation of the phylum cyanobacteria.
Molecular surveys of aphotic habitats have indicated the presence of major uncultured lineages phylogenetically classified as members of the Cyanobacteria. One of these lineages has recently been proposed as a nonphotosynthetic sister phylum to the Cyanobacteria, the Melainabacteria, based on recovery of population genomes from human gut and groundwater samples. Here, we expand the phylogenomic representation of the Melainabacteria through sequencing of six diverse population genomes from gut and bioreactor samples supporting the inference that this lineage is nonphotosynthetic, but not the assertion that they are strictly fermentative. We propose that the Melainabacteria is a class within the phylogenetically defined Cyanobacteria based on robust monophyly and shared ancestral traits with photosynthetic representatives. Our findings are consistent with theories that photosynthesis occurred late in the Cyanobacteria and involved extensive lateral gene transfer and extends the recognized functionality of members of this phylum.
Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland, Australia.
Rochelle M
RM
Soo
Connor T
CT
Skennerton
Yuji
Y
Sekiguchi
Michael
M
Imelfort
Samuel J
SJ
Paech
Paul G
PG
Dennis
Jason A
JA
Steen
Donovan H
DH
Parks
Gene W
GW
Tyson
Philip
P
Hugenholtz
D000818:Animals; D005075:Biological Evolution; D019149:Bioreactors / Q000382:microbiology*; D000458:Cyanobacteria / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D005243:Feces / Q000382:microbiology; D005828:Genetics, Population; D016680:Genome, Bacterial; D008297:Male; D048368:Phascolarctidae / Q000382:microbiology*; D010788:Photosynthesis; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S; D014865:Waste Disposal, Fluid / Q000295:instrumentation / Q000379:methods
D012336:RNA, Ribosomal, 16S
Melainabacteria; culture-independent; evolution; photosynthesis