Environmental genomics reveals a single-species ecosystem deep within Earth.

Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
Science (Impact Factor: 31.48). 10/2008; 322(5899):275-8. DOI: 10.1126/science.1155495
Source: PubMed

ABSTRACT DNA from low-biodiversity fracture water collected at 2.8-kilometer depth in a South African gold mine was sequenced and assembled into a single, complete genome. This bacterium, Candidatus Desulforudis audaxviator, composes >99.9% of the microorganisms inhabiting the fluid phase of this particular fracture. Its genome indicates a motile, sporulating, sulfate-reducing, chemoautotrophic thermophile that can fix its own nitrogen and carbon by using machinery shared with archaea. Candidatus Desulforudis audaxviator is capable of an independent life-style well suited to long-term isolation from the photosphere deep within Earth's crust and offers an example of a natural ecosystem that appears to have its biological component entirely encoded within a single genome.

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