A hydrogen-based subsurface microbial community dominated by methanogens.
Nature
; 415(6869): 312-5, 2002 Jan 17.
Article
em En
| MEDLINE
| ID: mdl-11797006
ABSTRACT
The search for extraterrestrial life may be facilitated if ecosystems can be found on Earth that exist under conditions analogous to those present on other planets or moons. It has been proposed, on the basis of geochemical and thermodynamic considerations, that geologically derived hydrogen might support subsurface microbial communities on Mars and Europa in which methanogens form the base of the ecosystem. Here we describe a unique subsurface microbial community in which hydrogen-consuming, methane-producing Archaea far outnumber the Bacteria. More than 90% of the 16S ribosomal DNA sequences recovered from hydrothermal waters circulating through deeply buried igneous rocks in Idaho are related to hydrogen-using methanogenic microorganisms. Geochemical characterization indicates that geothermal hydrogen, not organic carbon, is the primary energy source for this methanogen-dominated microbial community. These results demonstrate that hydrogen-based methanogenic communities do occur in Earth's subsurface, providing an analogue for possible subsurface microbial ecosystems on other planets.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Ecossistema
/
Euryarchaeota
Idioma:
En
Ano de publicação:
2002
Tipo de documento:
Article