title: Aerobic and nitrite-dependent methane-oxidizing microorganisms in sediments of freshwater lakes on the Yunnan Plateau.
abstract: Both aerobic methane-oxidizing bacteria (MOB) and nitrite-dependent anaerobic methane oxidation (n-damo) bacteria can play an important role in mitigating the methane emission produced in anoxic sediment layers to the atmosphere. However, the environmental factors regulating the distribution of these methane-oxidizing microorganisms in lacustrine ecosystems remain essentially unclear. The present study investigated the distribution of aerobic MOB and n-damo bacteria in sediments of various freshwater lakes on the Yunnan Plateau (China). Quantitative PCR assay and clone library analysis illustrated the spatial variations in the abundances and structures of aerobic MOB and n-damo bacterial communities. Type I MOB (Methylosoma and Methylobacter) and type II MOB (Methylocystis) were detected, while type I MOB was more abundant than type II MOB. Lake sediments n-damo bacterial communities were composed of novel Methylomirabilis oxyfera-like pmoA genes. Lake sediments in the same geographic region could share a relatively similar aerobic MOB community structure. Moreover, Pearson's correlation analysis indicated that n-damo pmoA gene diversity showed a positive correlation with the ratio of organic matter to total nitrogen in lake sediment.
authors.affiliation: Key Laboratory of Water and Sediment Sciences (Ministry of Education), College of Environmental Sciences and Engineering, Peking University, Beijing, 100871, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Liu
authors.forename: Jingxu
authors.initials: J
authors.lastname: Zhang
authors.forename: Lei
authors.initials: L
authors.lastname: Zhao
authors.forename: Yuzhao
authors.initials: Y
authors.lastname: Li
authors.forename: Yuyin
authors.initials: Y
authors.lastname: Yang
authors.forename: Shuguang
authors.initials: S
authors.lastname: Xie
mesh_terms: D000332:Aerobiosis; D001419:Bacteria / Q000145:classification* / Q000378:metabolism*; D058448:Biota; D002681:China; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D005618:Fresh Water; D019015:Geologic Sediments / Q000382:microbiology*; D060106:Lakes / Q000382:microbiology*; D008697:Methane / Q000378:metabolism*; D008969:Molecular Sequence Data; D009573:Nitrites / Q000378:metabolism*; D010084:Oxidation-Reduction; D060888:Real-Time Polymerase Chain Reaction; D017422:Sequence Analysis, DNA
chemical_list: D004269:DNA, Bacterial; D009573:Nitrites; D008697:Methane