Defining boundaries for the distribution of microbial communities beneath the sediment-buried, hydrothermally active seafloor.

ABSTRACT: Subseafloor microbes beneath active hydrothermal vents are thought to live near the upper temperature limit for life on Earth. We drilled and cored the Iheya North hydrothermal field in the Mid-Okinawa Trough, and examined the phylogenetic compositions and the products of metabolic functions of sub-vent microbial communities. We detected microbial cells, metabolic activities and molecular signatures only in the shallow sediments down to 15.8 m below the seafloor at a moderately distant drilling site from the active hydrothermal vents (450 m). At the drilling site, the profiles of methane and sulfate concentrations and the δ¹³C and δD isotopic compositions of methane suggested the laterally flowing hydrothermal fluids and the in situ microbial anaerobic methane oxidation. In situ

SUBMITTER: Yanagawa K 

PROVIDER: S-EPMC5270560 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature