title: Nitrite-dependent anaerobic methane oxidizing bacteria along the water level fluctuation zone of the Three Gorges Reservoir.
abstract: The nitrite-dependent anaerobic methane oxidation (n-damo) mediated by "Candidatus Methylomirabilis oxyfera" connects the biogeochemical carbon and nitrogen cycles in a novel way. Many environments have been reported to harbor such organism being slow-growing and oxygen-sensitive anaerobes. Here, we focused on the population of n-damo bacteria in a fluctuating habitat being the wetland in the water level fluctuation zone (WLFZ) of the Three Gorges Reservoir (TGR) in China. A molecular approach demonstrated positive amplifications when targeting the functional pmoA gene only in the lower sites which endured longer flooding time in an elevation gradient. Only 1 operational taxonomic unit (OTU) in the lower elevation zone targeting the 16S ribosomal RNA (rRNA) gene was clustering into the NC-10 group a, which is presumed to be the true n-damo group. Moreover, a relatively low level of diversity was observed in this study. The abundances were as low as 4.7 × 10(2) to 1.5 × 10(3) copies g(-1) dry soil (ds) in the initial stage, which were almost the lowest reported. However, an increase was observed (3.2 × 10(3) to 5.3 × 10(4) copies g(-1) ds) after nearly 6 months of flooding. Intriguingly, the abundance of n-damo bacteria correlated positively with the accumulated flooding time (AFT). The current study revealed that n-damo bacteria can be detected in a fluctuating environment and the sites with longer flooding time seem to be preferred habitats. The water flooding may be the principal factor in this ecosystem by creating anoxic condition. The wide range of such habitats suggests a high potential of n-damo bacteria to play a key role in natural CH4 consumption.
authors.affiliation: Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, China.
authors.forename: Pei
authors.initials: P
authors.lastname: Huang
authors.affiliation: Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Ye
authors.affiliation: Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, China.
authors.forename: Liyan
authors.initials: L
authors.lastname: Song
authors.affiliation: Department of Microbiology, IWWR, Radboud University Nijmegen, Nijmegen, 6525AJ, the Netherlands.
authors.forename: Huub J M
authors.initials: HJM
authors.lastname: Op den Camp
authors.affiliation: Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.
authors.forename: Guibing
authors.initials: G
authors.lastname: Zhu
authors.affiliation: Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, China. wsj@cigit.ac.cn.
authors.forename: Shengjun
authors.initials: S
authors.lastname: Wu
mesh_terms: D000332:Aerobiosis; D058491:Bacterial Load; D044822:Biodiversity; D002681:China; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D008772:Methylococcaceae / Q000145:classification* / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D009573:Nitrites / Q000378:metabolism*; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology; D053833:Wetlands
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D009573:Nitrites; D012336:RNA, Ribosomal, 16S
keywords: M. oxyfera-like bacteria; Nitrite-dependent anaerobic methane oxidation; Three gorges reservoir; Water flooding; Water level fluctuation zone