Microbial diversity in the deep sea and the underexplored "rare biosphere".
The evolution of marine microbes over billions of years predicts that the composition of microbial communities should be much greater than the published estimates of a few thousand distinct kinds of microbes per liter of seawater. By adopting a massively parallel tag sequencing strategy, we show that bacterial communities of deep water masses of the North Atlantic and diffuse flow hydrothermal vents are one to two orders of magnitude more complex than previously reported for any microbial environment. A relatively small number of different populations dominate all samples, but thousands of low-abundance populations account for most of the observed phylogenetic diversity. This "rare biosphere" is very ancient and may represent a nearly inexhaustible source of genomic innovation. Members of the rare biosphere are highly divergent from each other and, at different times in earth's history, may have had a profound impact on shaping planetary processes.
Sogin
Mitchell L
ML
Josephine Bay Paul Center, Marine Biological Laboratory at Woods Hole, 7 MBL Street, Woods Hole, MA 02543, USA. sogin@mbl.edu
Morrison
Hilary G
HG
Huber
Julie A
JA
Mark Welch
David
D
Huse
Susan M
SM
Neal
Phillip R
PR
Arrieta
Jesus M
JM
Herndl
Gerhard J
GJ
D044822:Biodiversity; D030541:Databases, Genetic; D017753:Ecosystem; D004783:Environmental Microbiology; D019143:Evolution, Molecular; D014644:Genetic Variation; D008386:Marine Biology / Q000379:methods*; D010802:Phylogeny; D012623:Seawater; D017422:Sequence Analysis, DNA; D013696:Temperature; D014871:Water Microbiology