title: Diversity and distribution of planktonic anaerobic ammonium-oxidizing bacteria in the Dongjiang River, China.
abstract: Anaerobic ammonium-oxidizing (anammox) process has recently been recognized as an important pathway for removing fixed nitrogen (N) from aquatic ecosystems. Anammox organisms are widely distributed in freshwater environments. However, little is known about their presence in the water column of riverine ecosystems. Here, the existence of a diverse anammox community was revealed in the water column of the Dongjiang River by analyzing 16S rRNA and hydrazine oxidation (hzo) genes of anammox bacteria. Phylogenetic analyses of hzo genes showed that Candidatus Jettenia related clades of anammox bacteria were dominant in the river, suggesting the ecological microniche distinction from freshwater/estuary and marine anammox bacteria with Ca. Brocadia and Kuenenia genera mainly detected in freshwater/estuary ecosystems, and Ca. Scalindua genus mainly detected in marine ecosystems. The abundance and diversity of anammox bacteria along the river were both significantly correlated with concentrations of NH4(+)-N based on Pearson and partial correlation analyses. Redundancy analyses showed the contents of NH4(+)-N, NO3(-)-N and the ratio of NH4(+)-N to NO2(-)-N significantly influenced the spatial distributions of anammox bacteria in the water column of the Dongjiang River. These results expanded our understanding of the distribution and potential roles of anammox bacteria in the water column of the river ecosystem.
authors.affiliation: Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou 510070, China; School of Bioscience and Bioengineering, South China University of Technology, Guangzhou 510070, China; State Key Laboratory of Applied Microbiology Southern China, Guangzhou 510070, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Sun
authors.affiliation: Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou 510070, China; State Key Laboratory of Applied Microbiology Southern China, Guangzhou 510070, China.
authors.forename: Chunyu
authors.initials: C
authors.lastname: Xia
authors.affiliation: Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou 510070, China; State Key Laboratory of Applied Microbiology Southern China, Guangzhou 510070, China. Electronic address: xumy@gdim.cn.
authors.forename: Meiying
authors.initials: M
authors.lastname: Xu
authors.affiliation: Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou 510070, China; State Key Laboratory of Applied Microbiology Southern China, Guangzhou 510070, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Guo
authors.affiliation: Harbin Institute of Technology, Harbin 150090, China.
authors.forename: Aijie
authors.initials: A
authors.lastname: Wang
authors.affiliation: Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, Guangzhou 510070, China; State Key Laboratory of Applied Microbiology Southern China, Guangzhou 510070, China. Electronic address: guopingsun@163.com.
authors.forename: Guoping
authors.initials: G
authors.lastname: Sun
mesh_terms: D064751:Ammonium Compounds / Q000378:metabolism; D001421:Bacteria, Anaerobic / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification* / Q000378:metabolism; D044822:Biodiversity; D002681:China; D017753:Ecosystem; D005798:Genes, Bacterial; D020459:Genes, rRNA; D006834:Hydrazines / Q000378:metabolism; D010084:Oxidation-Reduction; D010802:Phylogeny; D010933:Plankton / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D000644:Quaternary Ammonium Compounds / Q000378:metabolism; D012336:RNA, Ribosomal, 16S; D045483:Rivers / Q000737:chemistry / Q000382:microbiology*; D017422:Sequence Analysis, DNA
chemical_list: D064751:Ammonium Compounds; D006834:Hydrazines; D000644:Quaternary Ammonium Compounds; D012336:RNA, Ribosomal, 16S
keywords: 16S rRNA gene; Anammox; Dongjiang River; Hydrazine oxidation gene