title: Vertical profiles of water and sediment denitrifiers in two plateau freshwater lakes.
abstract: The present study investigated the abundance, richness, diversity, and community composition of denitrifiers (based on nirS and nosZ genes) in the stratified water columns and sediments in eutrophic Dianchi Lake and mesotrophic Erhai Lake using quantitative PCR assay and high-throughput sequencing analysis. Both nirS- and nosZ denitrifiers were detected in waters of these two lakes. Surface water showed higher nosZ gene density than bottom water, and Dianchi Lake waters had larger nirS gene abundance than Erhai Lake waters. The abundance of sediment nirS- and nosZ denitrifiers in Dianchi Lake was larger than that in Erhai Lake. nirS richness and diversity and nosZ richness tended to increase with increasing sediment layer depth in both lakes. The distinct structure difference of sediment nirS- and nosZ denitrifier communities was found between in Dianchi Lake and Erhai Lake. These two lakes also differed greatly in water denitrifier community structure. Moreover, phylogenetic analysis indicated the presence of several different groups of nirS- or nosZ denitrifiers in both lakes. The novel nirS denitrifiers were abundant in both Dianchi Lake and Erhai Lake, while most of the obtained nosZ sequences could be affiliated with known genera.
authors.affiliation: Tianjin Key Laboratory of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China.
authors.forename: Guozhu
authors.initials: G
authors.lastname: Mao
authors.affiliation: Tianjin Key Laboratory of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Chen
authors.affiliation: State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, 100871, China.
authors.forename: Yuyin
authors.initials: Y
authors.lastname: Yang
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: Zhen
authors.initials: Z
authors.lastname: Wu
authors.affiliation: State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, 100871, China.
authors.forename: Tianli
authors.initials: T
authors.lastname: Tong
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.affiliation: State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, 100871, China. xiesg@pku.edu.cn.
authors.forename: Shuguang
authors.initials: S
authors.lastname: Xie
mesh_terms: D000840:Anisoles; D001419:Bacteria / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D001426:Bacterial Proteins / Q000235:genetics; D044822:Biodiversity; D058440:Denitrification; D004149:Dioxoles; D005618:Fresh Water / Q000032:analysis / Q000382:microbiology*; D019015:Geologic Sediments / Q000382:microbiology*; D059014:High-Throughput Nucleotide Sequencing; D060106:Lakes / Q000032:analysis / Q000382:microbiology*; D017705:Lignans; D059013:Microbial Consortia / Q000235:genetics; D009572:Nitrite Reductases / Q000235:genetics; D010802:Phylogeny; D016133:Polymerase Chain Reaction
chemical_list: D000840:Anisoles; D001426:Bacterial Proteins; D004149:Dioxoles; D017705:Lignans; C475933:nirtetralin; D009572:Nitrite Reductases
keywords: Denitrifier; Freshwater lake; Vertical change; nirS; nosZ