This phenomenon has developed into a fascinating story about the production from nitrite of cryptic oxygen inside bacterial cells in anoxic environments (c.f. Nitrite-driven anaerobic methane oxidation by oxygenic bacteria, Ettwig; et al., NATURE 464 (7288 ) 543)
But aren't nitrate levels in the arctic ocean as low as they are in the world ocean, which is too low to be an electron acceptor, unlike sulfate? = Stuart = Stuart E. Strand 490 Ben Hall IDR Bldg. Box 355014, Univ. Washington Seattle, WA 98195 voice 206-543-5350, fax 206-685-9996 skype: stuartestrand http://faculty.washington.edu/sstrand/ -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Rau, Greg Sent: Thursday, October 13, 2011 7:35 PM To: [email protected] Subject: [geo] Anaerobic methane oxidation Relevant? Old news? Should be lots of nitrate and sulfate in the Arctic, at least in the ocean. Not sure if possible N2O or NO2 production is a good idea, though. - Greg Nature 440, 918-921 (13 April 2006) | doi:10.1038/nature04617; Received 30 November 2005; Accepted 2 February 2006 A microbial consortium couples anaerobic methane oxidation to denitrification Ashna A. Raghoebarsing1, Arjan Pol1, Katinka T. van de Pas-Schoonen1, Alfons J. P. Smolders2, Katharina F. Ettwig1, W. Irene C. Rijpstra3, Stefan Schouten3, Jaap S. Sinninghe Damsté3, Huub J. M. Op den Camp1, Mike S. M. Jetten1 & Marc Strous1 Department of Microbiology, and Department of Aquatic Ecology and Environmental Biology, Institute for Water and Wetland Research, Radboud University Nijmegen, Toernooiveld 1, 6525 ED Nijmegen, The Netherlands Royal Netherlands Institute for Sea Research (NIOZ), Department of Marine Biogeochemistry and Toxicology, PO Box 59, 1790 AB Den Burg, The Netherlands Correspondence to: Marc Strous1 Correspondence and requests for materials should be addressed to M.S. (Email: [email protected]). The 16S rRNA gene sequences have been deposited in GenBank under accession numbers DQ369741 (archaeal sequence) and DQ369742 (bacterial sequence). Top of pageAbstract Modern agriculture has accelerated biological methane and nitrogen cycling on a global scale1, 2. Freshwater sediments often receive increased downward fluxes of nitrate from agricultural runoff and upward fluxes of methane generated by anaerobic decomposition3. In theory, prokaryotes should be capable of using nitrate to oxidize methane anaerobically, but such organisms have neither been observed in nature nor isolated in the laboratory4, 5, 6, 7, 8. Microbial oxidation of methane is thus believed to proceed only with oxygen or sulphate9, 10. Here we show that the direct, anaerobic oxidation of methane coupled to denitrification of nitrate is possible. A microbial consortium, enriched from anoxic sediments, oxidized methane to carbon dioxide coupled to denitrification in the complete absence of oxygen. This consortium consisted of two microorganisms, a bacterium representing a phylum without any cultured species and an archaeon distantly related to marine methanotrophic Archaea. The detection of relatives of these prokaryotes in different freshwater ecosystems worldwide11, 12, 13, 14 indicates that the reaction presented here may make a substantial contribution to biological methane and nitrogen cycles. -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en. -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en.
