title: Manganese- and iron-dependent marine methane oxidation.
abstract: Anaerobic methanotrophs help regulate Earth's climate and may have been an important part of the microbial ecosystem on the early Earth. The anaerobic oxidation of methane (AOM) is often thought of as a sulfate-dependent process, despite the fact that other electron acceptors are more energetically favorable. Here, we show that microorganisms from marine methane-seep sediment in the Eel River Basin in California are capable of using manganese (birnessite) and iron (ferrihydrite) to oxidize methane, revealing that marine AOM is coupled, either directly or indirectly, to a larger variety of oxidants than previously thought. Large amounts of manganese and iron are provided to oceans from rivers, indicating that manganese- and iron-dependent AOM have the potential to be globally important.
authors: Department of Geosciences and Penn State Astrobiology Research Center, Pennsylvania State University, University Park, PA 16802, USA. ejbeal@gmail.com
authors: Emily J
authors: EJ
authors: Beal
authors: Christopher H
authors: CH
authors: House
authors: Victoria J
authors: VJ
authors: Orphan
mesh_terms: D000693:Anaerobiosis; D001105:Archaea / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D001439:Bacteroides / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D002140:California; D002245:Carbon Dioxide / Q000378:metabolism; D019615:Crenarchaeota / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D019605:Euryarchaeota / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D005290:Ferric Compounds / Q000378:metabolism*; D019015:Geologic Sediments / Q000382:microbiology*; D008345:Manganese / Q000378:metabolism*; D008697:Methane / Q000378:metabolism*; D017019:Methanosarcinaceae / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D010087:Oxides / Q000378:metabolism*; D010802:Phylogeny; D020560:Proteobacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D013816:Thermodynamics
chemical_list: D005290:Ferric Compounds; D010087:Oxides; C505018:birnessite; D002245:Carbon Dioxide; D008345:Manganese; C092844:ferric oxyhydroxide; D008697:Methane