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Narayanan M, Natarajan D, Kandasamy S, Chinnathambi A, Ali Alharbi S, Karuppusamy I, Kathirvel B. Pyrite biomining proficiency of sulfur dioxygenase (SDO) enzyme extracted from Acidithiobacillus thiooxidans. Process Biochem 2021. [DOI: 10.1016/j.procbio.2021.09.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Kucera J, Lochman J, Bouchal P, Pakostova E, Mikulasek K, Hedrich S, Janiczek O, Mandl M, Johnson DB. A Model of Aerobic and Anaerobic Metabolism of Hydrogen in the Extremophile Acidithiobacillus ferrooxidans. Front Microbiol 2020; 11:610836. [PMID: 33329503 PMCID: PMC7735108 DOI: 10.3389/fmicb.2020.610836] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Accepted: 11/04/2020] [Indexed: 12/12/2022] Open
Abstract
Hydrogen can serve as an electron donor for chemolithotrophic acidophiles, especially in the deep terrestrial subsurface and geothermal ecosystems. Nevertheless, the current knowledge of hydrogen utilization by mesophilic acidophiles is minimal. A multi-omics analysis was applied on Acidithiobacillus ferrooxidans growing on hydrogen, and a respiratory model was proposed. In the model, [NiFe] hydrogenases oxidize hydrogen to two protons and two electrons. The electrons are used to reduce membrane-soluble ubiquinone to ubiquinol. Genetically associated iron-sulfur proteins mediate electron relay from the hydrogenases to the ubiquinone pool. Under aerobic conditions, reduced ubiquinol transfers electrons to either cytochrome aa 3 oxidase via cytochrome bc 1 complex and cytochrome c 4 or the alternate directly to cytochrome bd oxidase, resulting in proton efflux and reduction of oxygen. Under anaerobic conditions, reduced ubiquinol transfers electrons to outer membrane cytochrome c (ferrireductase) via cytochrome bc 1 complex and a cascade of electron transporters (cytochrome c 4, cytochrome c 552, rusticyanin, and high potential iron-sulfur protein), resulting in proton efflux and reduction of ferric iron. The proton gradient generated by hydrogen oxidation maintains the membrane potential and allows the generation of ATP and NADH. These results further clarify the role of extremophiles in biogeochemical processes and their impact on the composition of the deep terrestrial subsurface.
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Affiliation(s)
- Jiri Kucera
- Department of Biochemistry, Faculty of Science, Masaryk University, Brno, Czechia
| | - Jan Lochman
- Department of Biochemistry, Faculty of Science, Masaryk University, Brno, Czechia
| | - Pavel Bouchal
- Department of Biochemistry, Faculty of Science, Masaryk University, Brno, Czechia
| | - Eva Pakostova
- School of Biological Sciences, College of Natural Sciences, Bangor University, Bangor, United Kingdom
| | - Kamil Mikulasek
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology, Brno, Czechia
| | - Sabrina Hedrich
- Institute of Biosciences, Technische Universität (TU) Bergakademie Freiberg, Freiberg, Germany
| | - Oldrich Janiczek
- Department of Biochemistry, Faculty of Science, Masaryk University, Brno, Czechia
| | - Martin Mandl
- Department of Biochemistry, Faculty of Science, Masaryk University, Brno, Czechia
| | - D Barrie Johnson
- School of Biological Sciences, College of Natural Sciences, Bangor University, Bangor, United Kingdom
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Jiang H, Qin Y, Gadow SI, Ohnishi A, Fujimoto N, Li YY. Bio-hythane production from cassava residue by two-stage fermentative process with recirculation. BIORESOURCE TECHNOLOGY 2018; 247:769-775. [PMID: 30060412 DOI: 10.1016/j.biortech.2017.09.102] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 09/14/2017] [Accepted: 09/15/2017] [Indexed: 06/08/2023]
Abstract
The two-stage hythane fermentation of cassava residue low in protein, rich in iron, and deficient in nickel and cobalt, resulted in failure after long-term operation, showing a radical decrease in methane production along with an increase in volatile fatty acids (VFAs) accumulation in the second stage. Based on the gap between theoretical demand and existing content of nutrients, the effect of their additions on hythane fermentation was validated in the repeated batch experiment and continuous experiment. The proliferation of hydrolysis bacteria, acidogens, and hydrogen producing bacteria and methanogens was guaranteed by sufficient N (0.7g/L), S (30mg/L), Ni (1.0mg/L), and Co (1.0mg/L), and the metabolism of a sustainable hythane fermentation was recovered. In this optimal nutrient combination of above trace elements, the highest hythane yield (426m3 hythane with 27.7% of hydrogen from 1ton of cassava residue) was obtained.
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Affiliation(s)
- Hongyu Jiang
- Department of Fermentation Science, Faculty of Applied Bio-science, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 1568502, Japan
| | - Yu Qin
- Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, 6-6-06 Aza-Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8579, Japan
| | - S I Gadow
- Department of Agricultural Microbiology, Agriculture and Biology Research Division, National Research Centre, 33 EI Buhouth St., Dokki, Cairo 12622, Egypt
| | - Akihiro Ohnishi
- Department of Fermentation Science, Faculty of Applied Bio-science, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 1568502, Japan
| | - Naoshi Fujimoto
- Department of Fermentation Science, Faculty of Applied Bio-science, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 1568502, Japan
| | - Yu-You Li
- Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, 6-6-06 Aza-Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8579, Japan.
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Zhang X, Liu X, Liang Y, Fan F, Zhang X, Yin H. Metabolic diversity and adaptive mechanisms of iron- and/or sulfur-oxidizing autotrophic acidophiles in extremely acidic environments. ENVIRONMENTAL MICROBIOLOGY REPORTS 2016; 8:738-751. [PMID: 27337207 DOI: 10.1111/1758-2229.12435] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 05/30/2016] [Indexed: 06/06/2023]
Abstract
Many studies have investigated the mechanisms underlying the survival and growth of certain organisms in extremely acidic environments known to be harmful to most prokaryotes and eukaryotes. Acidithiobacillus and Leptospirillum spp. are dominant bioleaching bacteria widely used in bioleaching systems, which are characterized by extremely acidic environments. To survive and grow in such settings, these acidophiles utilize shared molecular mechanisms that allow life in extreme conditions. In this review, we have summarized the results of published genomic analyses, which underscore the ability of iron- and/or sulfur-oxidizing autotrophic acidophiles belonging to the genera Acidithiobacillus and Leptospirillum to adapt to acidic environmental conditions. Several lines of evidence point at the metabolic diversity and multiplicity of pathways involved in the survival of these organisms. The ability to thrive in adverse environments requires versatile activation of structural and functional adaptive responses, including bacterial adhesion, motility, and resistance to heavy metals. We have highlighted recent developments centered on the key survival mechanisms employed by dominant extremophiles, and have laid the foundation for future studies focused on the ability of acidophiles to thrive in extremely acidic environments.
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Affiliation(s)
- Xian Zhang
- School of Minerals Processing and Bioengineering, Central South University, Changsha, China
- Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha, China
| | - Xueduan Liu
- School of Minerals Processing and Bioengineering, Central South University, Changsha, China
- Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha, China
| | - Yili Liang
- School of Minerals Processing and Bioengineering, Central South University, Changsha, China
- Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha, China
| | - Fenliang Fan
- Key Laboratory of Plant Nutrition and Fertilizer, Beijing, China
| | - Xiaoxia Zhang
- Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture, Beijing, China
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Huaqun Yin
- School of Minerals Processing and Bioengineering, Central South University, Changsha, China
- Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha, China
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Raleiras P, Hammarström L, Lindblad P, Styring S, Magnuson A. Photoinduced reduction of the medial FeS center in the hydrogenase small subunit HupS from Nostoc punctiforme. J Inorg Biochem 2015; 148:57-61. [DOI: 10.1016/j.jinorgbio.2015.03.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 03/22/2015] [Accepted: 03/24/2015] [Indexed: 12/21/2022]
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Raleiras P, Kellers P, Lindblad P, Styring S, Magnuson A. Isolation and characterization of the small subunit of the uptake hydrogenase from the cyanobacterium Nostoc punctiforme. J Biol Chem 2013; 288:18345-52. [PMID: 23649626 DOI: 10.1074/jbc.m113.468587] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In nitrogen-fixing cyanobacteria, hydrogen evolution is associated with hydrogenases and nitrogenase, making these enzymes interesting targets for genetic engineering aimed at increased hydrogen production. Nostoc punctiforme ATCC 29133 is a filamentous cyanobacterium that expresses the uptake hydrogenase HupSL in heterocysts under nitrogen-fixing conditions. Little is known about the structural and biophysical properties of HupSL. The small subunit, HupS, has been postulated to contain three iron-sulfur clusters, but the details regarding their nature have been unclear due to unusual cluster binding motifs in the amino acid sequence. We now report the cloning and heterologous expression of Nostoc punctiforme HupS as a fusion protein, f-HupS. We have characterized the anaerobically purified protein by UV-visible and EPR spectroscopies. Our results show that f-HupS contains three iron-sulfur clusters. UV-visible absorption of f-HupS has bands ∼340 and 420 nm, typical for iron-sulfur clusters. The EPR spectrum of the oxidized f-HupS shows a narrow g = 2.023 resonance, characteristic of a low-spin (S = ½) [3Fe-4S] cluster. The reduced f-HupS presents complex EPR spectra with overlapping resonances centered on g = 1.94, g = 1.91, and g = 1.88, typical of low-spin (S = ½) [4Fe-4S] clusters. Analysis of the spectroscopic data allowed us to distinguish between two species attributable to two distinct [4Fe-4S] clusters, in addition to the [3Fe-4S] cluster. This indicates that f-HupS binds [4Fe-4S] clusters despite the presence of unusual coordinating amino acids. Furthermore, our expression and purification of what seems to be an intact HupS protein allows future studies on the significance of ligand nature on redox properties of the iron-sulfur clusters of HupS.
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Affiliation(s)
- Patrícia Raleiras
- Department of Chemistry, Ångström Laboratory, Uppsala University, SE-75120 Uppsala, Sweden
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Anaerobic sulfur metabolism coupled to dissimilatory iron reduction in the extremophile Acidithiobacillus ferrooxidans. Appl Environ Microbiol 2013; 79:2172-81. [PMID: 23354702 DOI: 10.1128/aem.03057-12] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Gene transcription (microarrays) and protein levels (proteomics) were compared in cultures of the acidophilic chemolithotroph Acidithiobacillus ferrooxidans grown on elemental sulfur as the electron donor under aerobic and anaerobic conditions, using either molecular oxygen or ferric iron as the electron acceptor, respectively. No evidence supporting the role of either tetrathionate hydrolase or arsenic reductase in mediating the transfer of electrons to ferric iron (as suggested by previous studies) was obtained. In addition, no novel ferric iron reductase was identified. However, data suggested that sulfur was disproportionated under anaerobic conditions, forming hydrogen sulfide via sulfur reductase and sulfate via heterodisulfide reductase and ATP sulfurylase. Supporting physiological evidence for H2S production came from the observation that soluble Cu(2+) included in anaerobically incubated cultures was precipitated (seemingly as CuS). Since H(2)S reduces ferric iron to ferrous in acidic medium, its production under anaerobic conditions indicates that anaerobic iron reduction is mediated, at least in part, by an indirect mechanism. Evidence was obtained for an alternative model implicating the transfer of electrons from S(0) to Fe(3+) via a respiratory chain that includes a bc(1) complex and a cytochrome c. Central carbon pathways were upregulated under aerobic conditions, correlating with higher growth rates, while many Calvin-Benson-Bassham cycle components were upregulated during anaerobic growth, probably as a result of more limited access to carbon dioxide. These results are important for understanding the role of A. ferrooxidans in environmental biogeochemical metal cycling and in industrial bioleaching operations.
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Valdés J, Pedroso I, Quatrini R, Dodson RJ, Tettelin H, Blake R, Eisen JA, Holmes DS. Acidithiobacillus ferrooxidans metabolism: from genome sequence to industrial applications. BMC Genomics 2008; 9:597. [PMID: 19077236 PMCID: PMC2621215 DOI: 10.1186/1471-2164-9-597] [Citation(s) in RCA: 325] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2008] [Accepted: 12/11/2008] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Acidithiobacillus ferrooxidans is a major participant in consortia of microorganisms used for the industrial recovery of copper (bioleaching or biomining). It is a chemolithoautrophic, gamma-proteobacterium using energy from the oxidation of iron- and sulfur-containing minerals for growth. It thrives at extremely low pH (pH 1-2) and fixes both carbon and nitrogen from the atmosphere. It solubilizes copper and other metals from rocks and plays an important role in nutrient and metal biogeochemical cycling in acid environments. The lack of a well-developed system for genetic manipulation has prevented thorough exploration of its physiology. Also, confusion has been caused by prior metabolic models constructed based upon the examination of multiple, and sometimes distantly related, strains of the microorganism. RESULTS The genome of the type strain A. ferrooxidans ATCC 23270 was sequenced and annotated to identify general features and provide a framework for in silico metabolic reconstruction. Earlier models of iron and sulfur oxidation, biofilm formation, quorum sensing, inorganic ion uptake, and amino acid metabolism are confirmed and extended. Initial models are presented for central carbon metabolism, anaerobic metabolism (including sulfur reduction, hydrogen metabolism and nitrogen fixation), stress responses, DNA repair, and metal and toxic compound fluxes. CONCLUSION Bioinformatics analysis provides a valuable platform for gene discovery and functional prediction that helps explain the activity of A. ferrooxidans in industrial bioleaching and its role as a primary producer in acidic environments. An analysis of the genome of the type strain provides a coherent view of its gene content and metabolic potential.
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Affiliation(s)
- Jorge Valdés
- Center for Bioinformatics and Genome Biology, Fundación Ciencia para la Vida, Facultad de Ciencias de la Salud, Universidad Andres Bello, Santiago, Chile.
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Kai T, Nagano T, Fukumoto T, Nakajima M, Takahashi T. Autotrophic growth of Acidithiobacillus ferrooxidans by oxidation of molecular hydrogen using a gas-liquid contactor. BIORESOURCE TECHNOLOGY 2007; 98:460-4. [PMID: 16500099 DOI: 10.1016/j.biortech.2006.01.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2005] [Revised: 01/03/2006] [Accepted: 01/04/2006] [Indexed: 05/06/2023]
Abstract
The iron-oxidizing bacterium, Acidithiobacillus ferrooxidans, was cultivated on a medium without ferrous iron. Molecular hydrogen and air were supplied to the medium. It was found that A. ferrooxidans could grow with hydrogen in the pH range between 2.0 and 3.5. A trickle-bed contactor was used to increase the dissolution rate of hydrogen. The doubling time was increased and the cell concentration reached 4.0 x 10(9) cells ml(-1) after 6 days. When the cells taken from the hydrogen medium were transferred back into the medium containing ferrous iron, the growth rate and the iron-oxidizing ability were the same as the predictions assuming that the microorganism grown with hydrogen was A. ferrooxidans.
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Affiliation(s)
- Takami Kai
- Department of Applied Chemistry and Chemical Engineering, Kagoshima University, Kagoshima 890-0065, Japan.
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Schröder O, Bleijlevens B, de Jongh TE, Chen Z, Li T, Fischer J, Förster J, Friedrich CG, Bagley KA, Albracht SPJ, Lubitz W. Characterization of a cyanobacterial-like uptake [NiFe] hydrogenase: EPR and FTIR spectroscopic studies of the enzyme from Acidithiobacillus ferrooxidans. J Biol Inorg Chem 2006; 12:212-33. [PMID: 17082918 DOI: 10.1007/s00775-006-0185-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2006] [Accepted: 09/27/2006] [Indexed: 10/24/2022]
Abstract
Electron paramagnetic resonance (EPR) and Fourier transform IR studies on the soluble hydrogenase from Acidithiobacillus ferrooxidans are presented. In addition, detailed sequence analyses of the two subunits of the enzyme have been performed. They show that the enzyme belongs to a group of uptake [NiFe] hydrogenases typical for Cyanobacteria. The sequences have also a close relationship to those of the H(2)-sensor proteins, but clearly differ from those of standard [NiFe] hydrogenases. It is concluded that the structure of the catalytic centre is similar, but not identical, to that of known [NiFe] hydrogenases. The active site in the majority of oxidized enzyme molecules, 97% in cells and more than 50% in the purified enzyme, is EPR-silent. Upon contact with H(2) these sites remain EPR-silent and show only a limited IR response. Oxidized enzyme molecules with an EPR-detectable active site show a Ni(r)*-like EPR signal which is light-sensitive at cryogenic temperatures. This is a novelty in the field of [NiFe] hydrogenases. Reaction with H(2) converts these active sites to the well-known Ni(a)-C* state. Illumination below 160 K transforms this state into the Ni(a)-L* state. The reversal, in the dark at 200 K, proceeds via an intermediate Ni EPR signal only observed with the H(2)-sensor protein from Ralstonia eutropha. The EPR-silent active sites in as-isolated and H(2)-treated enzyme are also light-sensitive as observed by IR spectra at cryogenic temperatures. The possible origin of the light sensitivity is discussed. This study represents the first spectral characterization of an enzyme of the group of cyanobacterial uptake hydrogenases.
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Affiliation(s)
- Olga Schröder
- Max-Volmer-Institut für Biophysikalische Chemie und Biochemie, Technische Universität Berlin, 10623, Berlin, Germany
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11
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Buhrke T, Löscher S, Lenz O, Schlodder E, Zebger I, Andersen LK, Hildebrandt P, Meyer-Klaucke W, Dau H, Friedrich B, Haumann M. Reduction of unusual iron-sulfur clusters in the H2-sensing regulatory Ni-Fe hydrogenase from Ralstonia eutropha H16. J Biol Chem 2005; 280:19488-95. [PMID: 15764814 DOI: 10.1074/jbc.m500601200] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The regulatory Ni-Fe hydrogenase (RH) from Ralstonia eutropha functions as a hydrogen sensor. The RH consists of the large subunit HoxC housing the Ni-Fe active site and the small subunit HoxB containing Fe-S clusters. The heterolytic cleavage of H(2) at the Ni-Fe active site leads to the EPR-detectable Ni-C state of the protein. For the first time, the simultaneous but EPR-invisible reduction of Fe-S clusters during Ni-C state formation was demonstrated by changes in the UV-visible absorption spectrum as well as by shifts of the iron K-edge from x-ray absorption spectroscopy in the wild-type double dimeric RH(WT) [HoxBC](2) and in a monodimeric derivative designated RH(stop) lacking the C-terminal 55 amino acids of HoxB. According to the analysis of iron EXAFS spectra, the Fe-S clusters of HoxB pronouncedly differ from the three Fe-S clusters in the small subunits of crystallized standard Ni-Fe hydrogenases. Each HoxBC unit of RH(WT) seems to harbor two [2Fe-2S] clusters in addition to a 4Fe species, which may be a [4Fe-3S-3O] cluster. The additional 4Fe-cluster was absent in RH(stop). Reduction of Fe-S clusters in the hydrogen sensor RH may be a first step in the signal transduction chain, which involves complex formation between [HoxBC](2) and tetrameric HoxJ protein, leading to the expression of the energy converting Ni-Fe hydrogenases in R. eutropha.
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Affiliation(s)
- Thorsten Buhrke
- Humboldt-Universität zu Berlin, Institut für Biologie/Mikrobiologie, Berlin, Germany
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Quentmeier A, Hellwig P, Bardischewsky F, Grelle G, Kraft R, Friedrich CG. Sulfur oxidation in Paracoccus pantotrophus: interaction of the sulfur-binding protein SoxYZ with the dimanganese SoxB protein. Biochem Biophys Res Commun 2004; 312:1011-8. [PMID: 14651972 DOI: 10.1016/j.bbrc.2003.11.021] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The central protein of the sulfur-oxidizing enzyme system of Paracoccus pantotrophus, SoxYZ, formed complexes with subunits associated and covalently bound. In denaturing SDS-polyacrylamide gel electrophoresis (PAGE) SoxY migrated at 12 and SoxZ at 16kDa. SDS-PAGE of homogeneous SoxYZ without reductant separated dimeric complexes of 25, 29, and 32kDa identified by the N-terminal amino acid sequences as SoxY-Y, SoxY-Z, and SoxZ-Z, and subunit cleavage by reduction suggested their linkage via protein disulfide bonds. SoxYZ was reversibly redox active between -0.25 and 0.2V, as monitored by a combined electrochemical and FTIR spectroscopic approach. The dimanganese SoxB protein (58.611Da) converted the covalently linked heterodimer SoxY-Z to SoxYZ with associated subunits which in turn aggregated to the heterotetramer Sox(YZ)(2). This reaction depended on time and the SoxB concentration, and demonstrated the interaction of these two Sox proteins.
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Affiliation(s)
- Armin Quentmeier
- Lehrstuhl für Technische Mikrobiologie, Fachbereich Chemietechnik, Universität Dortmund, Emil-Figge-Strasse 66, D44221, Dortmund, Germany
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Laska S, Lottspeich F, Kletzin A. Membrane-bound hydrogenase and sulfur reductase of the hyperthermophilic and acidophilic archaeon Acidianus ambivalens. MICROBIOLOGY (READING, ENGLAND) 2003; 149:2357-2371. [PMID: 12949162 DOI: 10.1099/mic.0.26455-0] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A sulfur reductase (SR) and a hydrogenase were purified from solubilized membrane fractions of anaerobically grown cells of the sulfur-dependent archaeon Acidianus ambivalens and the corresponding genes were sequenced. The SR reduced elemental sulfur with hydrogen as electron donor [45 U (mg protein)(-1)] in the presence of hydrogenase and either 2,3-dimethylnaphthoquinone (DMN) or cytochrome c in the enzyme assay. The SR could not be separated from the hydrogenase during purification without loss of activity, whereas the hydrogenase could be separated from the SR. The specific activity of the hydrogenase was 170 U (mg protein)(-1) with methyl viologen and 833 U (mg protein)(-1) with DMN as electron acceptors. Both holoenzymes showed molecular masses of 250 kDa. In SDS gels of active fractions, protein bands with apparent masses of 110 (SreA), 66 (HynL), 41 (HynS) and 29 kDa were present. Enriched hydrogenase fractions contained 14 micro mol Fe and 2 micromol Ni (g protein)(-1); in addition, 2.5 micromol Mo (g protein)(-1) was found in the membrane fraction. Two overlapping genomic cosmid clones were sequenced, encoding a five-gene SR cluster (sre) including the 110 kDa subunit gene (sreA), and a 12-gene hydrogenase cluster (hyn) including the large and small subunit genes and genes encoding proteins required for the maturation of NiFe hydrogenases. A phylogenetic analysis of the SR amino acid sequence revealed that the protein belonged to the DMSO reductase family of molybdoenzymes and that the family showed a novel clustering. A model of sulfur respiration in Acidianus developed from the biochemical results and the data of the amino acid sequence comparisons is discussed.
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Affiliation(s)
- Simone Laska
- Institute of Microbiology and Genetics, Darmstadt University of Technology, Schnittspahnstrasse 10, 64287 Darmstadt, Germany
| | - Friedrich Lottspeich
- Institute of Microbiology and Genetics, Darmstadt University of Technology, Schnittspahnstrasse 10, 64287 Darmstadt, Germany
| | - Arnulf Kletzin
- Institute of Microbiology and Genetics, Darmstadt University of Technology, Schnittspahnstrasse 10, 64287 Darmstadt, Germany
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Rother D, Friedrich CG. The cytochrome complex SoxXA of Paracoccus pantotrophus is produced in Escherichia coli and functional in the reconstituted sulfur-oxidizing enzyme system. BIOCHIMICA ET BIOPHYSICA ACTA 2002; 1598:65-73. [PMID: 12147345 DOI: 10.1016/s0167-4838(02)00332-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The heterodimeric c-type cytochrome complex SoxXA of Paracoccus pantotrophus was produced in Escherichia coli. The soxX and soxA genes, separated by two genes in the sox gene cluster of P. pantotrophus, were fused with ribosome binding sites optimal for E. coli and combined to give soxXA in pRD133.27. The cytochrome complex SoxXA was produced in E. coli M15 containing pRD133.27, pREP4 encoding the Lac repressor and plasmid pEC86, carrying essential cytochrome c maturation genes. SoxX and SoxA were formed in a ratio of about 2.5:1. SoxA appeared to be unstable when not complexed with SoxX. The cytochrome complex SoxXA, purified to homogeneity from periplasmic extracts of E. coli M15 (pRD133.27, pREP4, pEC86), exhibited identical biochemical and biophysical properties as compared to SoxXA of P. pantotrophus. Moreover, this cytochrome complex was shown to be equally catalytically active with respect to rates and reactivity with different sulfur substrates in the reconstituted sulfur-oxidizing enzyme system using homogeneous Sox-proteins of P. pantotrophus. Homogeneous SoxX was catalytically inactive.
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Affiliation(s)
- Dagmar Rother
- Lehrstuhl für Technische Mikrobiologie, Fachbereich Chemietechnik, Universität Dortmund, Dortmund, Germany
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15
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Ohmura N, Sasaki K, Matsumoto N, Saiki H. Anaerobic respiration using Fe(3+), S(0), and H(2) in the chemolithoautotrophic bacterium Acidithiobacillus ferrooxidans. J Bacteriol 2002; 184:2081-7. [PMID: 11914338 PMCID: PMC134942 DOI: 10.1128/jb.184.8.2081-2087.2002] [Citation(s) in RCA: 113] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The chemolithoautotrophic bacterium Acidithiobacillus ferrooxidans has been known as an aerobe that respires on iron and sulfur. Here we show that the bacterium could chemolithoautotrophically grow not only on H(2)/O(2) under aerobic conditions but also on H(2)/Fe(3+), H(2)/S(0), or S(0)/Fe(3+) under anaerobic conditions. Anaerobic respiration using Fe(3+) or S(0) as an electron acceptor and H(2) or S(0) as an electron donor serves as a primary energy source of the bacterium. Anaerobic respiration based on reduction of Fe(3+) induced the bacterium to synthesize significant amounts of a c-type cytochrome that was purified as an acid-stable and soluble 28-kDa monomer. The purified cytochrome in the oxidized form was reduced in the presence of the crude extract, and the reduced cytochrome was reoxidized by Fe(3+). Respiration based on reduction of Fe(3+) coupled to oxidation of a c-type cytochrome may be involved in the primary mechanism of energy production in the bacterium on anaerobic iron respiration.
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Affiliation(s)
- Naoya Ohmura
- Department of Bio-Science, Central Research Institute of Electric Power Industry, 1646 Abiko, Abiko-City Chiba 270-1194, Japan.
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Rother D, Henrich HJ, Quentmeier A, Bardischewsky F, Friedrich CG. Novel genes of the sox gene cluster, mutagenesis of the flavoprotein SoxF, and evidence for a general sulfur-oxidizing system in Paracoccus pantotrophus GB17. J Bacteriol 2001; 183:4499-508. [PMID: 11443084 PMCID: PMC95344 DOI: 10.1128/jb.183.15.4499-4508.2001] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The novel genes soxFGH were identified, completing the sox gene cluster of Paracoccus pantotrophus coding for enzymes involved in lithotrophic sulfur oxidation. The periplasmic SoxF, SoxG, and SoxH proteins were induced by thiosulfate and purified to homogeneity from the soluble fraction. soxF coded for a protein of 420 amino acids with a signal peptide containing a twin-arginine motif. SoxF was 37% identical to the flavoprotein FccB of flavocytochrome c sulfide dehydrogenase of Allochromatium vinosum. The mature SoxF (42,832 Da) contained 0.74 mol of flavin adenine dinucleotide per mol. soxG coded for a novel protein of 303 amino acids with a signal peptide containing a twin-arginine motif. The mature SoxG (29,657 Da) contained two zinc binding motifs and 0.90 atom of zinc per subunit of the homodimer. soxH coded for a periplasmic protein of 317 amino acids with a double-arginine signal peptide. The mature SoxH (32,317 Da) contained two metal binding motifs and 0.29 atom of zinc and 0.20 atom of copper per subunit of the homodimer. SoxXA, SoxYZ, SoxB, and SoxCD (C. G. Friedrich, A. Quentmeier, F. Bardischewsky, D. Rother, R. Kraft, S. Kostka, and H. Prinz, J. Bacteriol. 182:4476-4487, 2000) reconstitute a system able to perform thiosulfate-, sulfite-, sulfur-, and hydrogen sulfide-dependent cytochrome c reduction, and this system is the first described for oxidizing different inorganic sulfur compounds. SoxF slightly inhibited the rate of hydrogen sulfide oxidation but not the rate of sulfite or thiosulfate oxidation. From use of a homogenote mutant with an in-frame deletion in soxF and complementation analysis, it was evident that the soxFGH gene products were not required for lithotrophic growth with thiosulfate.
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Affiliation(s)
- D Rother
- Lehrstuhl für Technische Mikrobiologie, Fachbereich Chemietechnik, Universität Dortmund, Emil-Figge-Strasse 66, D-44221 Dortmund, Germany
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Bardischewsky F, Friedrich CG. Identification of ccdA in Paracoccus pantotrophus GB17: disruption of ccdA causes complete deficiency in c-type cytochromes. J Bacteriol 2001; 183:257-63. [PMID: 11114924 PMCID: PMC94873 DOI: 10.1128/jb.183.1.257-263.2001] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2000] [Accepted: 10/05/2000] [Indexed: 11/20/2022] Open
Abstract
A transposon Tn5-mob insertional mutant of Paracoccus pantotrophus GB17, strain TP43, was unable to oxidize thiosulfate aerobically or to reduce nitrite anaerobically, and the cellular yields were generally decreased by 11 to 20%. Strain TP43 was unable to form functional c-type cytochromes, as determined by difference spectroscopy and heme staining. However, formation of apocytochromes and their transport to the periplasm were not affected, as seen with SoxD, a c-type cytochrome associated with the periplasmic sulfite dehydrogenase homologue. The Tn5-mob-containing DNA region of strain TP43 was cloned into pSUP205 to produce pE18TP43. With the aid of pE18TP43 the corresponding wild-type gene region of 15 kb was isolated from a heterogenote recombinant to produce pEF15. Sequence analysis of 2.8 kb of the relevant region uncovered three open reading frames, designated ORFA, ccdA, and ORFB, with the latter being oriented divergently. ORFA and ccdA were constitutively cotranscribed as determined by primer extension analysis. In strain TP43 Tn5-mob was inserted into ccdA. The deduced ORFA product showed no similarity to any protein in databases. However, the ccdA gene product exhibited similarities to proteins assigned to different functions in bacteria, such as cytochrome c biogenesis. For these proteins at least six transmembrane helices are predicted with the potential to form a channel with two conserved cysteines. This structural identity suggests that these proteins transfer reducing equivalents from the cytoplasm to the periplasm and that the cysteines bring about this transfer to enable the various specific functions via specific redox mediators such as thioredoxins. CcdA of P. pantotrophus is 42% identical to a protein predicted by ORF2, and its location within the sox gene cluster coding for lithotrophic sulfur oxidation suggested a different function.
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Affiliation(s)
- F Bardischewsky
- Lehrstuhl für Technische Mikrobiologie, Fachbereich Chemietechnik, Universität Dortmund, D-44221 Dortmund, Germany
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Friedrich CG, Quentmeier A, Bardischewsky F, Rother D, Kraft R, Kostka S, Prinz H. Novel genes coding for lithotrophic sulfur oxidation of Paracoccus pantotrophus GB17. J Bacteriol 2000; 182:4677-87. [PMID: 10940005 PMCID: PMC111341 DOI: 10.1128/jb.182.17.4677-4687.2000] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The gene region coding for lithotrophic sulfur oxidation of Paracoccus pantotrophus GB17 is located on a 13-kb insert of plasmid pEG12. Upstream of the previously described six open reading frames (ORFs) soxABCDEF with a partial sequence of soxA and soxF (C. Wodara, F. Bardischewsky, and C. G. Friedrich, J. Bacteriol. 179:5014-5023, 1997), 4,350 bp were sequenced. The sequence completed soxA, and uncovered six new ORFs upstream of soxA, designated ORF1, ORF2, and ORF3, and soxXYZ. ORF1 could encode a 275-amino-acid polypeptide of 29,332 Da with a 61 to 63% similarity to LysR transcriptional regulators. ORF2 could encode a 245-amino-acid polypeptide of 26,022 Da with the potential to form six transmembrane helices and with a 48 to 51% similarity to proteins involved in redox transport in cytochrome c biogenesis. ORF3 could encode a periplasmic polypeptide of 186 amino acids of 20,638 Da with a similarity to thioredoxin-like proteins and with a putative signal peptide of 21 amino acids. Purified SoxXA, SoxYZ, and SoxB are essential for thiosulfate or sulfite-dependent cytochrome c reduction in vitro. N-terminal and internal amino acid sequences identified SoxX, SoxY, SoxZ, and SoxA to be coded by the respective genes. The molecular masses of the mature proteins determined by electrospray ionization spectroscopy (SoxX, 14,834 Da; SoxY, 11,094 Da; SoxZ, 11,717 Da; and SoxA, 30,452 Da) were identical or close to those deduced from the nucleotide sequence with differences for the covalent heme moieties. SoxXA represents a novel type of periplasmic c-type cytochromes, with SoxX as a monoheme and SoxA as a hybrid diheme cytochrome c. SoxYZ is an as-yet-unprecedented soluble protein. SoxY has a putative signal peptide with a twin arginine motif and possibly cotransports SoxZ to the periplasm. SoxYZ neither contains a metal nor a complex redox center, as proposed for proteins likely to be transported via the Tat system.
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Affiliation(s)
- C G Friedrich
- Lehrstuhl für Technische Mikrobiologie, Universität Dortmund, D-44227 Dortmund, Germany.
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Ishii M, Takishita S, Iwasaki T, Peerapornpisal Y, Yoshino J, Kodama T, Igarashi Y. Purification and characterization of membrane-bound hydrogenase from Hydrogenobacter thermophilus strain TK-6, an obligately autotrophic, thermophilic, hydrogen-oxidizing bacterium. Biosci Biotechnol Biochem 2000; 64:492-502. [PMID: 10803945 DOI: 10.1271/bbb.64.492] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A membrane-bound hydrogenase was purified to electrophoretic homogeneity from the cells of Hydrogenobacter thermophilus strain TK-6, an obligately autotrophic, thermophilic, hydrogen-oxidizing bacterium. Solubilization and purification were done aerobically in the presence of Triton X-100. Three chromatography steps were done for purification; Butyl-Sepharose, Mono-Q, and Superose 6, in this order. Purification was completed with 6.73% yield of total activity and with 21.4-fold increase of specific activity when compared with the values for the membrane fraction. The purified hydrogenase was shown to be a tetramer with alpha2beta2 structure, with a molecular mass of 60,000 Da for the large subunit and 38,000 Da for the small subunit. The purified hydrogenase directly reduced methionaquinone with an apparent Km of around 300 microM and with a turnover number around 2900 (min(-1)). Metal analysis and EPR properties of the hydrogenase have shown that the enzyme is one of the [NiFe]-hydrogenases. Also, optimum pH and temperature for reaction, thermal stability, and electron acceptor specificity were reported. Finally, a model is presented for energy and central metabolism of H. thermophilus strain TK-6.
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Affiliation(s)
- M Ishii
- Department of Biotechnology, the University of Tokyo, Japan
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Ng KY, Sawada R, Inoue S, Kamimura K, Sugio T. Purification and some properties of sulfur reductase from the iron-oxidizing bacterium Thiobacillus ferrooxidans NASF-1. J Biosci Bioeng 2000; 90:199-203. [PMID: 16232842 DOI: 10.1016/s1389-1723(00)80110-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2000] [Accepted: 05/23/2000] [Indexed: 11/26/2022]
Abstract
Thiobacillus ferrooxidans strain NASF-1 grown aerobically in an Fe2+ (3%)-medium produces hydrogen sulfide (H2S) from elemental sulfur under anaerobic conditions with argon gas at pH 7.5. Sulfur reductase, which catalyzes the reduction of elemental sulfur (S0) with NAD(P)H as an electron donor to produce hydrogen sulfide (H2S) under anaerobic conditions, was purified 69-fold after 35-65% ammonium sulfate precipitation and Q-Sepharose FF, Phenyl-Toyopearl 650 ML, and Blue Sepharose FF column chromatography, with a specific activity of 57.6 U (mg protein)(-1). The purified enzyme was quite labile under aerobic conditions, but comparatively stable in the presence of sodium hydrosulfite and under anaerobic conditions, especially under hydrogen gas conditions. The purified enzyme showed both sulfur reductase and hydrogenase activities. Both activities had an optimum pH of 9.0. Sulfur reductase has an apparent molecular weight of 120,000 Da, and is composed of three different subunits (M(r) 54,000 Da (alpha), 36,000 Da (beta), and 35,000 Da (gamma)), as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This is the first report on the purification of sulfur reductase from a mesophilic and obligate chemolithotrophic iron-oxidizing bacterium.
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Affiliation(s)
- K Y Ng
- Division of Science and Technology for Energy Conversion, Graduate School of Natural Science and Technology, Okayama University, 1-1-1 Tsushima Naka, Okayama 700-8530, Japan
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YONG KIMNG, SAWADA RYOKO, INOUE SAYURI, KAMIMURA KAZUO, SUGIO TSUYOSHI. Purification and Some Properties of Sulfur Reductase from the Iron-Oxidizing Bacterium Thiobacillus ferrooxidans NASF-1. J Biosci Bioeng 2000. [DOI: 10.1263/jbb.90.199] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Abstract
Reduced inorganic sulfur compounds are oxidized by members of the domains Archaea and Bacteria. These compounds are used as electron donors for anaerobic phototrophic and aerobic chemotrophic growth, and are mostly oxidized to sulfate. Different enzymes mediate the conversion of various reduced sulfur compounds. Their physiological function in sulfur oxidation is considered (i) mostly from the biochemical characterization of the enzymatic reaction, (ii) rarely from the regulation of their formation, and (iii) only in a few cases from the mutational gene inactivation and characterization of the resulting mutant phenotype. In this review the sulfur-metabolizing reactions of selected phototrophic and of chemotrophic prokaryotes are discussed. These comprise an archaeon, a cyanobacterium, green sulfur bacteria, and selected phototrophic and chemotrophic proteobacteria. The genetic systems are summarized which are presently available for these organisms, and which can be used to study the molecular basis of their dissimilatory sulfur metabolism. Two groups of thiobacteria can be distinguished: those able to grow with tetrathionate and other reduced sulfur compounds, and those unable to do so. This distinction can be made irrespective of their phototrophic or chemotrophic metabolism, neutrophilic or acidophilic nature, and may indicate a mechanism different from that of thiosulfate oxidation. However, the core enzyme for tetrathionate oxidation has not been identified so far. Several phototrophic bacteria utilize hydrogen sulfide, which is considered to be oxidized by flavocytochrome c owing to its in vitro activity. However, the function of flavocytochrome c in vivo may be different, because it is missing in other hydrogen sulfide-oxidizing bacteria, but is present in most thiosulfate-oxidizing bacteria. A possible function of flavocytochrome c is discussed based on biophysical studies, and the identification of a flavocytochrome in the operon encoding enzymes involved in thiosulfate oxidation of Paracoccus denitrificans. Adenosine-5'-phosphosulfate reductase thought to function in the 'reverse' direction in different phototrophic and chemotrophic sulfur-oxidizing bacteria was analysed in Chromatium vinosum. Inactivation of the corresponding gene does not affect the sulfite-oxidizing ability of the mutant. This result questions the concept of its 'reverse' function, generally accepted for over three decades.
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Affiliation(s)
- C G Friedrich
- Lehrstuhl für Technische Mikrobiologie, Fachbereich Chemietechnik, Universität Dortmund, Germany
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Wodara C, Bardischewsky F, Friedrich CG. Cloning and characterization of sulfite dehydrogenase, two c-type cytochromes, and a flavoprotein of Paracoccus denitrificans GB17: essential role of sulfite dehydrogenase in lithotrophic sulfur oxidation. J Bacteriol 1997; 179:5014-23. [PMID: 9260941 PMCID: PMC179357 DOI: 10.1128/jb.179.16.5014-5023.1997] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
A 13-kb genomic region of Paracoccus dentrificans GB17 is involved in lithotrophic thiosulfate oxidation. Adjacent to the previously reported soxB gene (C. Wodara, S. Kostka, M. Egert, D. P. Kelly, and C. G. Friedrich, J. Bacteriol. 176:6188-6191, 1994), 3.7 kb were sequenced. Sequence analysis revealed four additional open reading frames, soxCDEF. soxC coded for a 430-amino-acid polypeptide with an Mr of 47,339 that included a putative signal peptide of 40 amino acids (Mr of 3,599) with a RR motif present in periplasmic proteins with complex redox centers. The mature soxC gene product exhibited high amino acid sequence similarity to the eukaryotic molybdoenzyme sulfite oxidase and to nitrate reductase. We constructed a mutant, GBsoxC delta, carrying an in-frame deletion in soxC which covered a region possibly coding for the molybdenum cofactor binding domain. GBsoxC delta was unable to grow lithoautotrophically with thiosulfate but grew well with nitrate as a nitrogen source or as an electron acceptor. Whole cells and cell extracts of mutant GBsoxC delta contained 10% of the thiosulfate-oxidizing activity of the wild type. Only a marginal rate of sulfite-dependent cytochrome c reduction was observed from cell extracts of mutant GBsoxC delta. These results demonstrated that sulfite dehydrogenase was essential for growth with thiosulfate of P. dentrificans GB17. soxD coded for a periplasmic diheme c-type cytochrome of 384 amino acids (Mr of 39,983) containing a putative signal peptide with an Mr of 2,363. soxE coded for a periplasmic monoheme c-type cytochrome of 236 amino acids (Mr of 25,926) containing a putative signal peptide with an Mr of 1,833. SoxD and SoxE were highly identical to c-type cytochromes of P. denitrificans and other organisms. soxF revealed an incomplete open reading frame coding for a peptide of 247 amino acids with a putative signal peptide (Mr of 2,629). The deduced amino acid sequence of soxF was 47% identical and 70% similar to the sequence of the flavoprotein of flavocytochrome c of Chromatium vinosum, suggesting the involvement of the flavoprotein in thiosulfate oxidation of P. denitrificans GB17.
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Affiliation(s)
- C Wodara
- Lehrstuhl für Technische Mikrobiologie, Fachbereich Chemietechnik, Universität Dortmund, Germany
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