Heterotrophic Archaea dominate sedimentary subsurface ecosystems off Peru

Studies of deeply buried, sedimentary microbial communities and associated biogeochemical processes during Ocean Drilling Program Leg 201 showed elevated prokaryotic cell numbers in sediment layers where methane is consumed anaerobically at the expense of sulfate. Here, we show that extractable archaeal rRNA, selecting only for active community members in these ecosystems, is dominated by sequences of uncultivated Archaea affiliated with the Marine Benthic Group B and the Miscellaneous Crenarchaeotal Group, whereas known methanotrophic Archaea are not detectable. Carbon flow reconstructions based on stable isotopic compositions of whole archaeal cells, intact archaeal membrane lipids, and other sedimentary…

• NS
  National Science Foundation

  Awards: NNA04CC06A, DGE-9972759, 9972759
• UD
  U.S. Department of Energy

  Awards: DGE-9972759, DE-FG02-, FG02-93ER20117, DE-FG02
• NA
  National Aeronautics and Space Administration

  Award: NNA04CC06A
• WM
  W. M. Keck Foundation
• GU
  G. Unger Vetlesen Foundation
• DF
  Deutsche Forschungsgemeinschaft
• UO
  University of California, Los Angeles
• DO
  Division of Graduate Education