Anaerobic Oxidation of Methane with Sulfate
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ANAEROBIC OXIDATION OF METHANE WITH SULFATE
Wimmer, R., Pester, L., and Eissmann, L., 2006. Das bernsteinführende Tertiär zwischen Leipzig und Bitterfeld. Mauritiana (Altenburg), 19, 373–421. Wolfe, A. P., Tappert, R., Muehlenbachs, K., Boudreau, M., McKellar, R. C., Basinger, J. F., and Garrett, A., 2009. A new proposal concerning the botanical origin of Baltic amber. Proceedings of the Royal Society B, 276, 3403–3412.
Cross-references Algae (Eukaryotic) Bacteria Biological Control on Diagenesis: Influence of Bacteria and Relevance to Ocean Acidification Biomarkers (Molecular Fossils) Diatoms Fungi and Lichens Geomycology Protozoa (Heterotroph, Eukaryotic)
ANAEROBIC OXIDATION OF METHANE WITH SULFATE Katrin Knittel, Antje Boetius Max Planck Institute for Marine Microbiology, Bremen, Germany
Definition Anaerobic oxidation of methane (AOM): microbially mediated oxidation of methane to CO2 by electron acceptors other than oxygen. Introduction Methane is the most abundant hydrocarbon in the atmosphere, and an important greenhouse gas (see Methane, Origin). A great deal of research has focused on the cause and climatic consequences of the variation in fluxes of methane to the atmosphere, throughout the Earth’s history. Three key functional groups of microbial organisms play a central role in regulating the fluxes of methane on the Earth, namely the methanogens, the aerobic methanotrophic bacteria, and the more recently discovered anaerobic methanotrophic archaea (ANME). It is estimated that AOM is a major sink for methane on the Earth, and of similar relevance as its photooxidation in the atmosphere (Hinrichs and Boetius, 2002; Reeburgh, 2007). Today, most methane is produced by methanogenesis, i.e., the final step in the fermentation of organic matter taking place in soils, wetlands, landfills, rice fields, freshwater and marine sediments, as well as in the guts of animals. Almost all of the methane produced in ocean sediments is consumed by AOM within the sulfate penetrated seafloor zones. Hence, the ocean does not contribute significantly to the atmospheric methane budget (40 µm in diameter (Nauhaus et al., 2007; Holler, unpublished data). After reaching a specific size they appear to burst, releasing single cells into the environment (Figure 2ab). The ANME-3 clade also belongs to the order Methanosarcinales and is closely related to cultivated species of the genus Methanococcoides with 95% 16S rRNA sequence similarity (Figure 1a). They form shelltype aggregates with a Desulfobulbus population as sulfate-reducing partner, however, only very few bacterial cells are associated (Figure 2y–z, aa).
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ANAEROBIC OXIDATION OF METHANE WITH SULFATE
Anaerobic Oxidation of Methane with Sulfate, Figure 1 (Continued)
ANAEROBIC OXIDATION OF METHANE WITH SULFATE
Identification of ANME by methyl coenzyme M reductase gene phylogeny The first genomic and proteomic analyses of sediments and microbial mats naturally enriched in the ANME biomass revealed a nickel protein similar to methyl coenzyme M reductase (MCR) as well as
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