Methane fuels deep-sea, rock-hosted ecosystem

Abstract

Microbial consortia at and below the seafloor thrive on methane emerging from underground seeps, oxidizing much of this gas long before it reaches the atmosphere. Newly discovered communities actively consume methane while living inside carbonate rocks. Endolithic methanotrophic microbes recovered from Hydrate Ridge off the Oregon Coast serve as an energy source for other constituents of this marine ecosystem. Marine Benthic Group B archaea are the most prominent lineages in off-seep background sediments. Among bacteria, Deltaproteobacteria are the most abundant lineage in nearly all samples from active seep sites, reflecting their role as sulfatereducing partners in anaerobic methane oxidation.