title: Methylotrophic methanogenesis governs the biogenic coal bed methane formation in Eastern Ordos Basin, China.
abstract: To identify themethanogenic pathways present in a deep coal bed methane (CBM) reservoir associated with Eastern Ordos Basin in China, a series of geochemical and microbiological studies was performed using gas and water samples produced from the Liulin CBM reservoir. The composition and stable isotopic ratios of CBM implied a mixed biogenic and thermogenic origin of the methane. Archaeal 16S rRNA gene analysis revealed the dominance of the methylotrophic methanogen Methanolobus in the water produced. The high potential of methane production by methylotrophic methanogens was found in the enrichments using the water samples amended with methanol and incubated at 25 and 35 °C. Methylotrophic methanogens were the dominant archaea in both enrichments as shown by polymerase chain reaction (PCR)–denaturing gradient gel electrophoresis (DGGE). Bacterial 16S rRNA gene analysis revealed that fermentative, sulfate-reducing, and nitrate-reducing bacteria inhabiting the water produced were a factor in coal biodegradation to fuel methanogens. These results suggested that past and ongoing biodegradation of coal by methylotrophic methanogens and syntrophic bacteria, as well as thermogenic CBM production, contributed to the Liulin CBM reserves associated with the Eastern Ordos Basin.
authors.affiliation: College of Resources and Environment, Graduate University of Chinese Academy of Sciences, 19 A Yuquan Road, Beijing 100049, People’s Republic of China.
authors.forename: Hongguang
authors.initials: H
authors.lastname: Guo
authors.forename: Zhisheng
authors.initials: Z
authors.lastname: Yu
authors.forename: Ruyin
authors.initials: R
authors.lastname: Liu
authors.forename: Hongxun
authors.initials: H
authors.lastname: Zhang
authors.forename: Qiding
authors.initials: Q
authors.lastname: Zhong
authors.forename: Zhenghe
authors.initials: Z
authors.lastname: Xiong
mesh_terms: D001105:Archaea / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism*; D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism*; D002681:China; D003031:Coal / Q000382:microbiology*; D019641:DNA, Archaeal / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics / Q000378:metabolism; D008697:Methane / Q000378:metabolism*; D008969:Molecular Sequence Data; D010802:Phylogeny; D012623:Seawater / Q000382:microbiology*
chemical_list: D003031:Coal; D019641:DNA, Archaeal; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D008697:Methane