Activity and distribution of thermophilic prokaryotes in hydrothermal fluid, sulfidic structures, and sheaths of alvinellids (East Pacific Rise, 13°N).

ABSTRACT: Processes of inorganic carbon assimilation, methanogenesis, sulfate reduction, and acetate oxidation to CO(2) occurring in samples from the East Pacific Rise at 13°N were traced, using radioisotopically labeled substrates, at temperatures ranging from 65 to 100°C. Molecular hydrogen stimulated lithotrophic methanogenesis and sulfate reduction but inhibited inorganic carbon assimilation. Active mineralization of acetate was observed in an organic-rich Alvinella-associated system at 80°C. Members of the Thermococcales were the most numerous hyperthermophilic archaea in these samples, their density achieving 10(8) cells per cm(3), while the numbers of cultured hydrogen-utilizing thermophilic lithotrophs were several orders of magnitude lower.

SUBMITTER: Bonch-Osmolovskaya EA 

PROVIDER: S-EPMC3126372 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature