title: Functional genes and thermophilic microorganisms responsible for arsenite oxidation from the shallow sediment of an untraversed hot spring outlet.
abstract: Hot Springs have unique geochemical features. Microorganisms-mediated arsenite oxidation is one of the major biogeochemical processes occurred in some hot springs. This study aimed to understand the diversities of genes and microorganisms involved in arsenite oxidation from the outlet of an untraversed hot spring located at an altitude of 4226 m. Microcosm assay indicated that the microbial community from the hot spring was able to efficiently oxidize As(III) using glucose, lactic acid, yeast extract or sodium bicarbonate as the sole carbon source. The microbial community contained 7 phyla of microorganisms, of which Proteobacteria and Firmicutes are largely dominant; this composition is unique and differs significantly from those of other described hot springs. Twenty one novel arsenite oxidase genes were identified from the samples, which are affiliated with the arsenite oxidase families of α-Proteobacteria, β-Proteobacteria or Archaea; this highlights the high diversity of the arsenite-oxidizing microorganisms from the hot spring. A cultivable arsenite-oxidizer Chelatococcu sp. GHS311 was also isolated from the sample using enrichment technique. It can completely convert 75.0 mg/L As(III) into As(V) in 18 days at 45 °C. The arsenite oxidase of GHS311 shares the maximal sequence identity (84.7%) to that of Hydrogenophaga sp. CL3, a non-thermotolerant bacterium. At the temperature lower than 30 °C or higher than 65 °C, the growth of this strain was completely inhibited. These data help us to better understand the diversity and functional features of the thermophilic arsenite-oxidizing microorganisms from hot springs.
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology & Department of Biological Science and Technology, School of Environmental Studies, China University of Geosciences (Wuhan), Wuhan, 430074, People's Republic of China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology & Department of Biological Science and Technology, School of Environmental Studies, China University of Geosciences (Wuhan), Wuhan, 430074, People's Republic of China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Mu
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology & Department of Biological Science and Technology, School of Environmental Studies, China University of Geosciences (Wuhan), Wuhan, 430074, People's Republic of China. xianchun.zeng@gmail.com.
authors.forename: Xian-Chun
authors.initials: XC
authors.lastname: Zeng
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology & Department of Biological Science and Technology, School of Environmental Studies, China University of Geosciences (Wuhan), Wuhan, 430074, People's Republic of China.
authors.forename: Weiwei
authors.initials: W
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology & Department of Biological Science and Technology, School of Environmental Studies, China University of Geosciences (Wuhan), Wuhan, 430074, People's Republic of China.
authors.forename: Jie
authors.initials: J
authors.lastname: Yuan
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology & Department of Biological Science and Technology, School of Environmental Studies, China University of Geosciences (Wuhan), Wuhan, 430074, People's Republic of China.
authors.forename: Yichen
authors.initials: Y
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology & Department of Biological Science and Technology, School of Environmental Studies, China University of Geosciences (Wuhan), Wuhan, 430074, People's Republic of China.
authors.forename: E
authors.initials: E
authors.lastname: Guoji
authors.affiliation: School of Medicine, Jianghan University, Wuhan, 430056, People's Republic of China. luofeng2015@jhun.edu.cn.
authors.forename: Feng
authors.initials: F
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology & Department of Biological Science and Technology, School of Environmental Studies, China University of Geosciences (Wuhan), Wuhan, 430074, People's Republic of China.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology & Department of Biological Science and Technology, School of Environmental Studies, China University of Geosciences (Wuhan), Wuhan, 430074, People's Republic of China.
authors.forename: Hao
authors.initials: H
authors.lastname: Li
authors.affiliation: State Key Laboratory of Biogeology and Environmental Geology & Department of Biological Science and Technology, School of Environmental Studies, China University of Geosciences (Wuhan), Wuhan, 430074, People's Republic of China.
authors.forename: Jianing
authors.initials: J
authors.lastname: Wang
mesh_terms: D001105:Archaea / Q000235:genetics; D018053:Arsenites / Q000032:analysis / Q000378:metabolism*; D019015:Geologic Sediments / Q000737:chemistry; D045482:Hot Springs; D006863:Hydrogen-Ion Concentration; D010084:Oxidation-Reduction; D000071436:Thermotolerance / Q000235:genetics*; D014871:Water Microbiology; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000378:metabolism*
chemical_list: D018053:Arsenites; D014874:Water Pollutants, Chemical
keywords: Arsenite oxidase; Arsenite-oxidizing microorganisms; Extremophile; Hot spring; Microbial community; Thermophilic microorganism