title: Thiosulfate transfer mediated by DsrE/TusA homologs from acidothermophilic sulfur-oxidizing archaeon Metallosphaera cuprina.
abstract: Conserved clusters of genes encoding DsrE and TusA homologs occur in many archaeal and bacterial sulfur oxidizers. TusA has a well documented function as a sulfurtransferase in tRNA modification and molybdenum cofactor biosynthesis in Escherichia coli, and DsrE is an active site subunit of the DsrEFH complex that is essential for sulfur trafficking in the phototrophic sulfur-oxidizing Allochromatium vinosum. In the acidothermophilic sulfur (S(0))- and tetrathionate (S4O6(2-))-oxidizing Metallosphaera cuprina Ar-4, a dsrE3A-dsrE2B-tusA arrangement is situated immediately between genes encoding dihydrolipoamide dehydrogenase and a heterodisulfide reductase-like complex. In this study, the biochemical features and sulfur transferring abilities of the DsrE2B, DsrE3A, and TusA proteins were investigated. DsrE3A and TusA proved to react with tetrathionate but not with NaSH, glutathione persulfide, polysulfide, thiosulfate, or sulfite. The products were identified as protein-Cys-S-thiosulfonates. DsrE3A was also able to cleave the thiosulfate group from TusA-Cys(18)-S-thiosulfonate. DsrE2B did not react with any of the sulfur compounds tested. DsrE3A and TusA interacted physically with each other and formed a heterocomplex. The cysteine residue (Cys(18)) of TusA is crucial for this interaction. The single cysteine mutants DsrE3A-C(93)S and DsrE3A-C(101)S retained the ability to transfer the thiosulfonate group to TusA. TusA-C(18)S neither reacted with tetrathionate nor was it loaded with thiosulfate with DsrE3A-Cys-S-thiosulfonate as the donor. The transfer of thiosulfate, mediated by a DsrE-like protein and TusA, is unprecedented not only in M. cuprina but also in other sulfur-oxidizing prokaryotes. The results of this study provide new knowledge on oxidative microbial sulfur metabolism.
authors.affiliation: State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China,; University of Chinese Academy of Sciences, Beijing 100049, China, and.
authors.forename: Li-Jun
authors.initials: LJ
authors.lastname: Liu
authors.affiliation: Institut für Mikrobiologie & Biotechnologie, Rheinische Friedrich-Wilhems-Universität Bonn, 53115 Bonn, Germany.
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Stockdreher
authors.affiliation: Institut für Mikrobiologie & Biotechnologie, Rheinische Friedrich-Wilhems-Universität Bonn, 53115 Bonn, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Koch
authors.affiliation: Core Facility and Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Shu-Tao
authors.initials: ST
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Fan
authors.affiliation: Institut für Medizinische Mikrobiologie, Immunologie und Parasitologie, Abteilung Pharmazeutische Mikrobiologie, Rheinische Friedrich-Wilhelms-Universität Bonn, 53127 Bonn, Germany.
authors.forename: Michaele
authors.initials: M
authors.lastname: Josten
authors.affiliation: Institut für Medizinische Mikrobiologie, Immunologie und Parasitologie, Abteilung Pharmazeutische Mikrobiologie, Rheinische Friedrich-Wilhelms-Universität Bonn, 53127 Bonn, Germany.
authors.forename: Hans-Georg
authors.initials: HG
authors.lastname: Sahl
authors.affiliation: State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Yuan-Ming
authors.initials: YM
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China,; Environmental Microbiology Research Center, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China,. Electronic address: liusj@im.ac.cn.
authors.forename: Shuang-Jiang
authors.initials: SJ
authors.lastname: Liu
authors.affiliation: Institut für Mikrobiologie & Biotechnologie, Rheinische Friedrich-Wilhems-Universität Bonn, 53115 Bonn, Germany,. Electronic address: ChDahl@uni-bonn.de.
authors.forename: Christiane
authors.initials: C
authors.lastname: Dahl
authors.affiliation: State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China,; Environmental Microbiology Research Center, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China,. Electronic address: jiangcy@im.ac.cn.
authors.forename: Cheng-Ying
authors.initials: CY
authors.lastname: Jiang
mesh_terms: D019943:Amino Acid Substitution; D019843:Archaeal Proteins / Q000235:genetics / Q000378:metabolism*; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D046912:Multiprotein Complexes / Q000235:genetics / Q000378:metabolism*; D020125:Mutation, Missense; D010084:Oxidation-Reduction; D017386:Sequence Homology, Amino Acid; D016943:Sulfolobaceae / Q000235:genetics / Q000378:metabolism*; D013455:Sulfur / Q000378:metabolism*; D013466:Sulfurtransferases / Q000235:genetics / Q000378:metabolism*
chemical_list: D019843:Archaeal Proteins; D002352:Carrier Proteins; D046912:Multiprotein Complexes; D013455:Sulfur; D013466:Sulfurtransferases
keywords: Archaea; DsrE/TusA-like Proteins; Energy Metabolism; Metallosphaera cuprina; Microbiology; Oxidation-Reduction (Redox); Sulfur; Tetrathionate; Thiosulfate Transfer