Heterotrophic Archaea dominate sedimentary subsurface ecosystems off Peru

@article{citeulike:2776714, abstract = {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 carbon pools indicate that these Archaea assimilate sedimentary organic compounds other than methane even though methanotrophy accounts for a major fraction of carbon cycled in these ecosystems. Oxidation of methane by members of Marine Benthic Group B and the Miscellaneous Crenarchaeotal Group without assimilation of methane-carbon provides a plausible explanation. Maintenance energies of these subsurface communities appear to be orders of magnitude lower than minimum values known from laboratory observations, and ecosystem-level carbon budgets suggest that community turnover times are on the order of 100-2,000 years. Our study provides clues about the metabolic functionality of two cosmopolitan groups of uncultured Archaea. 10.1073/pnas.0600035103}, author = {Biddle, Jennifer F. and Lipp, Julius S. and Lever, Mark A. and Lloyd, Karen G. and Sorensen, Ketil B. and Anderson, Rika and Fredricks, Helen F. and Elvert, Marcus and Kelly, Timothy J. and Schrag, Daniel P. and Sogin, Mitchell L. and Brenchley, Jean E. and Teske, Andreas and House, Christopher H. and Hinrichs, Kai-Uwe }, citeulike-article-id = {2776714}, doi = {10.1073/pnas.0600035103}, journal = {Proceedings of the National Academy of Sciences}, keywords = {16srrna, archaea, fish, lipids}, month = {March}, number = {10}, pages = {3846--3851}, posted-at = {2008-05-09 22:44:01}, priority = {2}, title = {Heterotrophic Archaea dominate sedimentary subsurface ecosystems off Peru}, url = {http://dx.doi.org/10.1073/pnas.0600035103}, volume = {103}, year = {2006} }

TY - JOUR ID - citeulike:2776714 L3 - citeulike-article-id:2776714 TI - Heterotrophic Archaea dominate sedimentary subsurface ecosystems off Peru JF - Proceedings of the National Academy of Sciences VL - 103 IS - 10 SP - 3846 EP - 3851 N2 - 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 carbon pools indicate that these Archaea assimilate sedimentary organic compounds other than methane even though methanotrophy accounts for a major fraction of carbon cycled in these ecosystems. Oxidation of methane by members of Marine Benthic Group B and the Miscellaneous Crenarchaeotal Group without assimilation of methane-carbon provides a plausible explanation. Maintenance energies of these subsurface communities appear to be orders of magnitude lower than minimum values known from laboratory observations, and ecosystem-level carbon budgets suggest that community turnover times are on the order of 100-2,000 years. Our study provides clues about the metabolic functionality of two cosmopolitan groups of uncultured Archaea. 10.1073/pnas.0600035103 KW - 16srrna KW - archaea KW - fish KW - lipids AU - Biddle, Jennifer AU - Lipp, Julius AU - Lever, Mark AU - Lloyd, Karen AU - Sorensen, Ketil AU - Anderson, Rika AU - Fredricks, Helen AU - Elvert, Marcus AU - Kelly, Timothy AU - Schrag, Daniel AU - Sogin, Mitchell AU - Brenchley, Jean AU - Teske, Andreas AU - House, Christopher AU - Hinrichs, Kai-Uwe PY - 2006/03/07/ UR - http://dx.doi.org/10.1073/pnas.0600035103 ER -