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Achim Kroger - One of the best experts on this subject based on the ideXlab platform.
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solution structure of the 30 kda polysulfide sulfur transferase homodimer from Wolinella succinogenes
Biochemistry, 2004Co-Authors: Felician Dancea, Achim Kroger, Oliver Klimmek, Frank Lohr, Stefania Pfeiffermarek, Michael Nilges, Hans Wienk, Heinz RuterjansAbstract:The periplasmic polysulfide-sulfur transferase (Sud) protein encoded by Wolinella succinogenes is involved in oxidative phosphorylation with polysulfide-sulfur as a terminal electron acceptor. The polysulfide-sulfur is covalently bound to the catalytic Cys residue of the Sud protein and transferred to the active site of the membranous polysulfide reductase. The solution structure of the homodimeric Sud protein has been determined using heteronuclear multidimensional NMR techniques. The structure is based on NOE-derived distance restraints, backbone hydrogen bonds, and torsion angle restraints as well as residual dipolar coupling restraints for a refinement of the relative orientation of the monomer units. The monomer structure consists of a five-stranded parallel ‚-sheet enclosing a hydrophobic core, a two-stranded antiparallel ‚-sheet, and six R-helices. The dimer fold is stabilized by hydrophobic residues and ion pairs found in the contact area between the two monomers. Similar to rhodanese enzymes, Sud catalyzes the transfer of the polysulfide-sulfur to the artificial acceptor cyanide. Despite their similar functions and active sites, the amino acid sequences and structures of these proteins are quite different.
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multifrequency cw epr investigation of the catalytic molybdenum cofactor of polysulfide reductase from Wolinella succinogenes
Journal of Biological Inorganic Chemistry, 2003Co-Authors: Thomas F Prisner, Achim Kroger, Sevdalina Lyubenova, Yener Atabay, Fraser Macmillan, Oliver KlimmekAbstract:Electron paramagnetic resonance (EPR) spectra of the molybdenum centre in polysulfide reductase (Psr) from Wolinella succinogenes with unusually high G-tensor values have been observed for the first time. Three different MoV states have been generated (by the addition of the substrate polysulfide and different redox agents) and analysed by their G- and hyperfine tensors using multifrequency (S-, X- and Q-band) cw-EPR spectroscopy. The unusually high G-tensor values are attributed to a large number of sulfur ligands. Four sulfur ligands are assumed to arise from two pterin cofactors; one additional sulfur ligand was identified from mutagenesis studies to be a cysteine residue of the protein backbone. One further sulfur ligand is proposed for two of the MoV states, based on the experimentally observed shift of the g av value. This sixth sulfur ligand is postulated to belong to the polysulfide substrate consumed within the catalytic reaction cycle of the enzyme. The influence of the co-protein sulfur transferase on the MoV G-tensor supports this assignment.
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psrr a member of the arac family of transcriptional regulators is required for the synthesis of Wolinella succinogenes polysulfide reductase
Archives of Microbiology, 2002Co-Authors: Stephan Braatsch, Jörg Simon, Oliver Klimmek, Roland Gross, Torsten Krafft, Achim KrogerAbstract:Wolinella succinogenes grows by polysulfide respiration with formate or hydrogen as electron donor. Polysulfide reduction is catalyzed by the membrane-bound polysulfide reductase complex encoded by the psrABC operon. An open reading frame, designated psrR, was found in close proximity upstream of the psr operon, but oriented in the opposite direction. The deduced amino acid sequence of PsrR is similar to those of transcriptional regulators of the AraC family and includes all typical features. Polysulfide reductase is not detectable in a ΔpsrR deletion mutant of W. succinogenes. Mutant cells grown with fumarate as terminal electron acceptor did not catalyze polysulfide reduction with formate or hydrogen, in contrast to the wild-type strain. The phenotype of W. succinogenes wild-type cells was restored by genomic complementation of W. succinogenes ΔpsrR. The results suggest that the gene product of psrR is involved in the regulation of polysulfide reductase synthesis.
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crystallization and preliminary x ray analysis of the membrane bound cytochrome c nitrite reductase complex nrfha from Wolinella succinogenes
Acta Crystallographica Section D-biological Crystallography, 2002Co-Authors: Oliver Einsle, Jörg Simon, Achim Kroger, Oliver Klimmek, Petra Stach, Albrecht Messerschmidt, Peter M H KroneckAbstract:Crystals of the complex between the enzyme cytochrome c nitrite reductase (NrfA) and the membrane-bound quinol oxidase and electron carrier NrfH were grown by vapour diffusion using ammonium sulfate as a precipitant. In the ∊-proteobacterium Wolinella succinogenes, NrfA and NrfH form a functional membrane-bound complex which catalyzes the last step in the metabolic pathway of nitrate dissimilation. NrfH represents a prototype of a large family of putative bacterial quinol oxidases, the NapC/NirT family, which have been proposed to serve as electron donors for a variety of reductases. Crystal growth of the NrfHA complex was strongly dependent on the presence of detergent; the crystals grown belonged to space group I422.
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fumarate respiration of Wolinella succinogenes enzymology energetics and coupling mechanism
Biochimica et Biophysica Acta, 2002Co-Authors: Achim Kroger, Jörg Simon, Gottfried Unden, Simone Biel, Roland Gross, Roy C D LancasterAbstract:Wolinella succinogenes performs oxidative phosphorylation with fumarate instead of O2 as terminal electron acceptor and H2 or formate as electron donors. Fumarate reduction by these donors ('fumarate respiration') is catalyzed by an electron transport chain in the bacterial membrane, and is coupled to the generation of an electrochemical proton potential (Deltap) across the bacterial membrane. The experimental evidence concerning the electron transport and its coupling to Deltap generation is reviewed in this article. The electron transport chain consists of fumarate reductase, menaquinone (MK) and either hydrogenase or formate dehydrogenase. Measurements indicate that the Deltap is generated exclusively by MK reduction with H2 or formate; MKH2 oxidation by fumarate appears to be an electroneutral process. However, evidence derived from the crystal structure of fumarate reductase suggests an electrogenic mechanism for the latter process.
Roy C D Lancaster - One of the best experts on this subject based on the ideXlab platform.
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an unconventional anaerobic membrane protein production system based on Wolinella succinogenes
Methods in Enzymology, 2015Co-Authors: Michael Lafontaine, Roy C D LancasterAbstract:Abstract In cases where membrane protein production attempts in more conventional Escherichia coli -based systems have failed, a solution is to resort to a system based on the nonpathogenic epsilon-proteobacterium Wolinella succinogenes . This approach has been demonstrated to be successful for structural and mechanistic analyses not only for homologous production of W . succinogenes membrane proteins but also for the heterologous production of membrane protein complexes from the human pathogens Helicobacter pylori and Campylobacter jejuni . The procedure to establish a system for the production of native and variant enzymes in W . succinogenes is presented in detail for the examples of the quinol:fumarate reductase and the SdhABE complexes of W . succinogenes . Subsequently, further projects using W . succinogenes as expression host are covered.
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design synthesis and biological testing of novel naphthoquinones as substrate based inhibitors of the quinol fumarate reductase from Wolinella succinogenes
Journal of Medicinal Chemistry, 2013Co-Authors: Hamid R Nasiri, Roy C D Lancaster, Michael Lafontaine, Gregor M Madej, Robin Panisch, Jan W Bats, Harald SchwalbeAbstract:Novel naphthoquinones were designed, synthesized, and tested as substrate-based inhibitors against the membrane-embedded protein quinol/fumarate reductase (QFR) from Wolinella succinogenes, a target closely related to QFRs from the human pathogens Helicobacter pylori and Campylobacter jejuni. For a better understanding of the hitherto structurally unexplored substrate binding pocket, a structure–activity relationship (SAR) study was carried out. Analogues of lawsone (2-hydroxy-1,4-naphthoquinone 3a) were synthesized that vary in length and size of the alkyl side chains (3b–k). A combined study on the prototropic tautomerism of 2-hydroxy-1,4-naphthoquinones series indicated that the 1,4-tautomer is the more stable and biologically relevant isomer and that the presence of the hydroxyl group is crucial for inhibition. Furthermore, 2-bromine-1,4-naphthoquinone (4a–c) and 2-methoxy-1,4-naphthoquinone (5a–b) series were also discovered as novel and potent inhibitors. Compounds 4a and 4b showed IC50 values in lo...
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Wolinella succinogenes quinol fumarate reductase and its comparison to e coli succinate quinone reductase
FEBS Letters, 2003Co-Authors: Roy C D LancasterAbstract:The three-dimensional structure of Wolinella succinogenes quinol:fumarate reductase (QFR), a dihaem-containing member of the superfamily of succinate:quinone oxidoreductases (SQOR), has been determined at 2.2 A resolution by X-ray crystallography [Lancaster et al., Nature 402 (1999) 377–385]. The structure and mechanism of W. succinogenes QFR and their relevance to the SQOR superfamily have recently been reviewed [Lancaster, Adv. Protein Chem. 63 (2003) 131–149]. Here, a comparison is presented of W. succinogenes QFR to the recently determined structure of the mono-haem containing succinate:quinone reductase from Escherichia coli [Yankovskaya et al., Science 299 (2003) 700–704]. In spite of differences in polypeptide and haem composition, the overall topology of the membrane anchors and their relative orientation to the conserved hydrophilic subunits is strikingly similar. A major difference is the lack of any evidence for a ‘proximal’ quinone site, close to the hydrophilic subunits, in W. succinogenes QFR.
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crystallization of Wolinella succinogenes quinol fumarate reductase
Membrane Protein Purification and Crystallization (Second Edition)#R##N#A Practical Guide, 2003Co-Authors: Roy C D LancasterAbstract:Quinol:fumarate reductases (QFR) and succinate:quinone reductases (SQR) catalyze the reduction of fumarate to succinate with concomitant oxidation of hydroquinone (quinol) to quinone, as well as the reverse reaction. SQR (respiratory complex II) is involved in aerobic metabolism as part of the citric acid cycle and the aerobic respiratory chain. QFR is involved in anaerobic respiration with fumarate as the terminal electron acceptor. QFR and SQR complexes are collectively referred to as succinate:quinone oxidoreductases and are predicted to share similar structures. The complexes consist of two hydrophilic and one or two hydrophobic membrane-integrated subunits. QFR of Wolinella succinogenes and SQR of Bacillus subtilis contain only one hydrophobic subunit (C) with two haem b groups. In contrast, SQR and QFR of Escherichia coli contain two hydrophobic subunits (C and D) that bind either one (SQR) or no haem b group (QFR). There are two principle types of membrane protein crystals. Type I crystals can be thought of as ordered stacks of two-dimensional crystals formed in the planes of the membrane. Type II crystals contain detergents bound in a micellar manner. They are held together via polar interactions between the polar surfaces of the membrane protein.
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fumarate respiration of Wolinella succinogenes enzymology energetics and coupling mechanism
Biochimica et Biophysica Acta, 2002Co-Authors: Achim Kroger, Jörg Simon, Gottfried Unden, Simone Biel, Roland Gross, Roy C D LancasterAbstract:Wolinella succinogenes performs oxidative phosphorylation with fumarate instead of O2 as terminal electron acceptor and H2 or formate as electron donors. Fumarate reduction by these donors ('fumarate respiration') is catalyzed by an electron transport chain in the bacterial membrane, and is coupled to the generation of an electrochemical proton potential (Deltap) across the bacterial membrane. The experimental evidence concerning the electron transport and its coupling to Deltap generation is reviewed in this article. The electron transport chain consists of fumarate reductase, menaquinone (MK) and either hydrogenase or formate dehydrogenase. Measurements indicate that the Deltap is generated exclusively by MK reduction with H2 or formate; MKH2 oxidation by fumarate appears to be an electroneutral process. However, evidence derived from the crystal structure of fumarate reductase suggests an electrogenic mechanism for the latter process.
Ingar Olsen - One of the best experts on this subject based on the ideXlab platform.
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comparison of lipopolysaccharides from bacteroides porphyromonas prevotella campylobacter and Wolinella spp by tricine sds page
Dental Traumatology, 1997Co-Authors: J Firoozkoohi, H Zandi, Ingar OlsenAbstract:: Lipopolysaccharides (LPSs) of 11 bacterial strains from the type species of the genera Bacteroides (B. fragilis), Prevotella (Pr. melaninogenica), Porphyromonas (Po. gingivalis), Campylobacter (C. fetus subsp. fetus), and Wolinella (W. succinogenes), and from the type strains of B. distasonis, B. forsythus, B. ureolyticus, Po. levii, Po. macacae, and C. gracilis, were extracted with hot water-phenol (Westphal method). S-form LPSs, obtained from all organisms, were well resolved with tricine-sodium-dodecyl-sulphate polyacrylamide gel electrophoresis and visualized by silver staining. Lipid A was not stained. Also profiles from LPS of Escherichia coli, serotypes 0111:B4 and 055:B5, could be distinguished. While W. succinogenes showed a relatively short S-form LPS on electrophoregrams, the other bacteria, including B. fragilis, exhibited long-ladder LPSs. Po. gingivalis displayed the largest number of bands and the longest O-chain. The long O-chain of this bacterium may be important for its virulence.
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Comparison of lipopolysaccharides from Bacteroides, Porphyromonas, Prevotella, Campylobacter and Wolinella spp. by Tricine-SDS-PAGE
Dental Traumatology, 1997Co-Authors: J Firoozkoohi, H Zandi, Ingar OlsenAbstract:Lipopolysaccharides (LPSs) of 11 bacterial strains from the type species of the genera Bacteroides (B, fragilis), Prevotella (Pr. melaninogenica), Porphyromonas (Po. gingivalis), Canmpylobacter (C. fetus subsp. fetus), and Wolinella (W. succinogens), and from the type strains of B. distasonis, B. forythus, B. ureolyticus, Po. levii, Po. macacae, and C. gracilis, were extracted with hot water-phenol (Westphal method). S-form LPSs, obtained from all organisms, were well resolved with tricine-sodium-dodecyl-sulphate polyacrylamide gel electrophoresis and visualized by silver staining. Lipid A was not stained. Also profiles from LPS of Escherichia coli, serotypes 0111:B4 and 055:B5, could be distinguished. While W. succinogenes showed a relatively short S-form LPS on electrophoregrams, the other bacteria, including B. fragilis, exhibited long-ladder LPSs. Po. gingivalis displayed the largest number of bands and the longest O-chain. The long O-chain of this bacterium may be important for its virulence.
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multivariate analyses of cellular fatty acids in bacteroides prevotella porphyromonas Wolinella and campylobacter spp
Journal of Clinical Microbiology, 1991Co-Authors: Ilia Brondz, Ingar OlsenAbstract:The genera Bacteroides, Wolinella, and Campylobacter contain several similar species that require taxonomic revision. Fatty acid profiles of whole bacterial cells have proven useful for taxonomy. In this study, cellular fatty acids from Bacteroides, Prevotella, Porphyromonas, Wolinella, and Campylobacter spp. were identified and quantitated by gas chromatography and gas chromatography-mass spectrometry, and the data were subjected to principal component analyses. Bacteroides fragilis, the type species of the genus Bacteroides, was distinct from the other organisms. While Bacteroides gracilis, Wolinella succinogenes, Wolinella curva, Wolinella recta, and Campylobacter fetus subsp. venerealis were close to each other, Prevotella (Bacteroides) buccae, Prevotella oralis, Prevotella oris, Prevotella disiens, Prevotella veroralis, Prevotella heparinolyticus, Porphyromonas (Bacteroides) endodontalis, and Bacteroides ureolyticus could be distinguished. B. fragilis was characterized by the presence of C3OH-i-1-, Ca-15, and Ci-15 and the absence of C12:0 and unsaturated fatty acids. For comparison, B. gracilis, B. ureolyticus, W. succinogenes, W. curva, W. recta, and Campylobacter fetus subsp. venerealis contained C12:0, C16:1, C18:1, and C3-OH-14 acids but lacked branched hydroxy and branched nonhydroxy acids. B. gracilis and B. ureolyticus are not "true" bacteroides.
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Three‐dimensional structure of the surface layer of Wolinella recta
Oral Microbiology and Immunology, 1990Co-Authors: Terje Dokland, Ingar Olsen, George Farrants, B.v. JohansenAbstract:The three-dimensional structure of the crystalline surface layer (S-layer) of Wolinella recta ATCC 33238T, a gram-negative, anaerobic periodontopathogen, was determined to 3.8 nm resolution by electron microscopy and digital image processing. The S-layer protein is closely associated with the outer bacterial membrane, and shows p6 symmetry with lattice spacing and thickness of 21 nm and 15 nm, respectively. The funnel-shaped subunits consist of 6 heavy domains located round a common base at the sixfold axis, and communicate with the adjacent subunits through a lighter domain at the threefold axis (M6C3 arrangement).
Jörg Simon - One of the best experts on this subject based on the ideXlab platform.
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tsdc a unique lipoprotein from Wolinella succinogenes that enhances tetrathionate reductase activity of tsda
Fems Microbiology Letters, 2017Co-Authors: Julia M Kurth, Jörg Simon, Anja Schuster, Waldemar Seel, Stefanie Herresthal, Christiane DahlAbstract:The diheme cytochromes c of the widespread TsdA family are bifunctional thiosulfate dehydrogenase/tetrathionate reductases. Here, biochemical information was collected about TsdA from the Epsilonproteobacterium Wolinella succinogenes ( Ws TsdA). The situation in W. succinogenes is unique since TsdA is closely associated with the unprecedented lipoprotein TsdC encoded immediately downstream of tsdA in the same direction of transcription. Ws TsdA purified from Escherichia coli catalyzed both thiosulfate oxidation and tetrathionate reduction. After co-production of TsdC and Ws TsdA in E. coli , TsdC was found to mediate membrane attachment of TsdA and to ensure its full catalytic activity. This effect was much stronger in the tetrathionate-reducing than in the thiosulfate-oxidizing direction. It is concluded that the TsdAC complex predominantly acts as a tetrathionate reductase in vivo .
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production and consumption of nitrous oxide in nitrate ammonifying Wolinella succinogenes cells
Microbiology, 2014Co-Authors: Monique Luckmann, Melanie Kern, Daniel Mania, Lars R Bakken, Asa Frostegard, Jörg SimonAbstract:Global warming is moving more and more into the public consciousness. Besides the commonly mentioned carbon dioxide and methane, nitrous oxide (N2O) is a powerful greenhouse gas in addition to its contribution to depletion of stratospheric ozone. The increasing concern about N2O emission has focused interest on underlying microbial energy-converting processes and organisms harbouring N2O reductase (NosZ), such as denitrifiers and ammonifiers of nitrate and nitrite. Here, the epsilonproteobacterial model organism Wolinella succinogenes is investigated with regard to its capacity to produce and consume N2O during growth by anaerobic nitrate ammonification. This organism synthesizes an unconventional cytochrome c nitrous oxide reductase (cNosZ), which is encoded by the first gene of an atypical nos gene cluster. However, W. succinogenes lacks a nitric oxide (NO)-producing nitrite reductase of the NirS- or NirK-type as well as an NO reductase of the Nor-type. Using a robotized incubation system, the wild-type strain and suitable mutants of W. succinogenes that either produced or lacked cNosZ were analysed as to their production of NO, N2O and N2 in both nitrate-sufficient and nitrate-limited growth medium using formate as electron donor. It was found that cells growing in nitrate-sufficient medium produced small amounts of N2O, which derived from nitrite and, most likely, from the presence of NO. Furthermore, cells employing cNosZ were able to reduce N2O to N2. This reaction, which was fully inhibited by acetylene, was also observed after adding N2O to the culture headspace. The results indicate that W. succinogenes cells are competent in N2O and N2 production despite being correctly grouped as respiratory nitrate ammonifiers. N2O production is assumed to result from NO detoxification and nitrosative stress defence, while N2O serves as a terminal electron acceptor in anaerobic respiration. The ecological implications of these findings are discussed.
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production of recombinant multiheme cytochromes c in Wolinella succinogenes
Methods in Enzymology, 2011Co-Authors: Melanie Kern, Jörg SimonAbstract:Respiratory nitrogen cycle processes like nitrification, nitrate reduction, denitrification, nitrite ammonification, or anammox involve a variety of dissimilatory enzymes and redox-active cofactors. In this context, an intriguing protein class are cytochromes c, that is, enzymes containing one or more covalently bound heme groups that are attached to heme c binding motifs (HBMs) of apo-cytochromes. The key enzyme of the corresponding maturation process is cytochrome c heme lyase (CCHL), an enzyme that catalyzes the formation of two thioether linkages between two vinyl side chains of a heme and two cysteine residues arranged in the HBM. In recent years, many multiheme cytochromes c involved in nitrogen cycle processes, such as hydroxylamine oxidoreductase and cytochrome c nitrite reductase, have attracted particular interest. Structurally, these enzymes exhibit conserved heme packing motifs despite displaying very different enzymic properties and largely unrelated primary structures. The functional and structural characterization of cytochromes c demands their purification in sufficient amounts as well as the feasibility to generate site-directed enzyme variants. For many interesting organisms, however, such systems are not available, mainly hampered by genetic inaccessibility, slow growth rates, insufficient cell yields, and/or a low capacity of cytochrome c formation. Efficient heterologous cytochrome c overproduction systems have been established using the unrelated proteobacterial species Escherichia coli and Wolinella succinogenes. In contrast to E. coli, W. succinogenes uses the cytochrome c biogenesis system II and contains a unique set of three specific CCHL isoenzymes that belong to the unusual CcsBA-type. Here, W. succinogenes is presented as host for cytochrome c overproduction focusing on a recently established gene expression system designed for large-scale production of multiheme cytochromes c.
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complete genome sequence and analysis of Wolinella succinogenes
Proceedings of the National Academy of Sciences of the United States of America, 2003Co-Authors: Claudia Baar, Jörg Simon, Oliver Klimmek, Roland Gross, Mark Eppinger, Guenter Raddatz, Christa Lanz, Ramkumar Nandakumar, Andrea Rosinus, Heike KellerAbstract:To understand the origin and emergence of pathogenic bacteria, knowledge of the genetic inventory from their nonpathogenic relatives is a prerequisite. Therefore, the 2.11-megabase genome sequence of Wolinella succinogenes, which is closely related to the pathogenic bacteria Helicobacter pylori and Campylobacter jejuni, was determined. Despite being considered nonpathogenic to its bovine host, W. succinogenes holds an extensive repertoire of genes homologous to known bacterial virulence factors. Many of these genes have been acquired by lateral gene transfer, because part of the virulence plasmid pVir and an N-linked glycosylation gene cluster were found to be syntenic between C. jejuni and genomic islands of W. succinogenes. In contrast to other host-adapted bacteria, W. succinogenes does harbor the highest density of bacterial sensor kinases found in any bacterial genome to date, together with an elaborate signaling circuitry of the GGDEF family of proteins. Because the analysis of the W. succinogenes genome also revealed genes related to soil- and plant-associated bacteria such as the nif genes, W. succinogenes may represent a member of the epsilon proteobacteria with a life cycle outside its host.
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modification of heme c binding motifs in the small subunit nrfh of the Wolinella succinogenes cytochrome c nitrite reductase complex
FEBS Letters, 2002Co-Authors: Jörg Simon, Simone Biel, Robert Eichler, Rene Pisa, Roland GrossAbstract:The two multiheme c-type cytochromes NrfH and NrfA form a membrane-bound complex that catalyzes menaquinol oxidation by nitrite during respiratory nitrite ammonification of Wolinella succinogenes. Each cysteine residue of the four NrfH heme c binding motifs was individually replaced by serine. Of the resulting eight W. succinogenes mutants, only one is able to grow by nitrite respiration although its electron transport activity from formate to nitrite is decreased. NrfH from this mutant was shown by matrix-assisted laser desorption/ionization mass spectrometry to carry four covalently bound heme groups like wild-type NrfH indicating that the cytochrome c biogenesis system II organism W. succinogenes is able to attach heme to an SXXCH motif.
Wolfram Schumacher - One of the best experts on this subject based on the ideXlab platform.
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cytochrome c nitrite reductase from sulfurospirillum deleyianum and Wolinella succinogenes
1998Co-Authors: Oliver Einsle, Wolfram Schumacher, E Kurun, U Nath, Peter M H KroneckAbstract:Within the biogeochemical nitrogen cycle NxOy compounds function as electron acceptors of anaerobic respiratory chains. Prokaryotes carry out their energy conservation during reduction of these nitrogen compounds, and use complex transition metal enzymes for their transformation [1,2]. Dissimilatory nitrate reduction proceeds via two different pathways, i.e. denitrification, and nitrate- ammonification (Scheme 1). In denitrification, the nitrite reductase is either a cytochrome cd 1, or a copper protein [3,4]. During nitrate-ammonification nitrate is reduced to nitrite as the only liberated intermediate that is subsequently converted to ammonia in a six-electron step by a cytochrome c nitrite reductase [4]. H2 and formate are the predominant electron donors that are oxidized by nitrate-ammonifying bacteria [5–7]. Eisenmann et al. [8] reported on the use of sulfide as electron donor to support bacterial growth by nitrate-ammonification, thus connecting the biogeochemical cycles of nitrogen and sulfur.
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ammonia forming cytochrome c nitrite reductase from sulfurospirillum deleyianum is a tetraheme protein new aspects of the molecular composition and spectroscopic properties
Biochemical and Biophysical Research Communications, 1994Co-Authors: Wolfram Schumacher, U Hole, M H KroneckAbstract:Abstract Ammonia-forming cytochrome c nitrite reductase from Sulfurospirillum deleyianum contains four covalently bound heme c groups/55 kDa subunit as determined by atomic absorption spectroscopy and the pyridine Fe(II)-hemochrome technique. Nitrite reductase was isolated from the membrane fraction as a monomer (M r 55±2 kDa) and as a heterooligomeric complex. Both the monomeric and the complex form of the enzyme exhibited a high specific activity, with up to 1050 μmol NO 2 − min −1 mg −1 . The complex was built from four 55 kDa units and contained a 22 kDa c-type cytochrome which was absent in the monomeric form. EPR spectra of the complex displayed a prominent feature at g 4.83 (baseline crossing). This resonance, which was not observed in the spectra of the monomeric nitrite reductase, was assigned to the 22 kDa c-type cytochrome subunit. Identical results were obtained for the enzyme from Wolinella succinogenes which had been reinvestigated for comparison.
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Comparative systematic study on “Spirillum” 5175, Campylobacter and Wolinella species
Archives of Microbiology, 1992Co-Authors: Wolfram Schumacher, Peter M H Kroneck, Norbert PfennigAbstract:Physiological tests, redetermination of G+C values with HPLC and DNA-DNA hybridization were used to determine the taxonomic affiliation of “Spirillum” 5175. This facultatively sulfur-reducing bacterium was compared to the type strains of the phenotypically most similar species Wolinella succinogenes and Campylobacter sputorum biovar bubulus . In addition to morphology, the following physiological properties were in common: use of elemental sulfur, nitrate, nitrite, aspartate, fumarate or malate as electron acceptor for growth with hydrogen or formate under anoxic conditions; microaerobic growth with 2% (v/v) oxygen. The G+C content of Wolinella succinogenes (51.8 mol%) and Campylobacter sputorum biovar bubulus (30.4 mol%) differs about 10 mol% from the G+C content of “Spirillum” 5175 (40.6 mol%). No significant DNA homology could be detected between the three strains. These differences excluded affiliation of “Spirillum” 5175 with the genera Wolinella or Campylobacter despite phenotypic similarities. On the basis of our results and DNA-rRNA hybridization studies by other authors, we established the new genus Sulfurospirillum for the freeliving Campylobacter -like bacteria “Spirillum” 5175 and “ Campylobacter spec.” DSM 806. Strain “Spirillum” 5175 is described as the type strain of the new genus and species Sulfurospirillum deleyianum .
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comparative systematic study on spirillum 5175 campylobacter and Wolinella species description of spirillum 5175 as sulfurospirillum deleyianum gen nov spec nov
Archives of Microbiology, 1992Co-Authors: Wolfram Schumacher, Peter M H Kroneck, Norbert PfennigAbstract:Physiological tests, redetermination of G+C values with HPLC and DNA-DNA hybridization were used to determine the taxonomic affiliation of “Spirillum” 5175. This facultatively sulfur-reducing bacterium was compared to the type strains of the phenotypically most similar species Wolinella succinogenes and Campylobacter sputorum biovar bubulus. In addition to morphology, the following physiological properties were in common: use of elemental sulfur, nitrate, nitrite, aspartate, fumarate or malate as electron acceptor for growth with hydrogen or formate under anoxic conditions; microaerobic growth with 2% (v/v) oxygen. The G+C content of Wolinella succinogenes (51.8 mol%) and Campylobacter sputorum biovar bubulus (30.4 mol%) differs about 10 mol% from the G+C content of “Spirillum” 5175 (40.6 mol%). No significant DNA homology could be detected between the three strains. These differences excluded affiliation of “Spirillum” 5175 with the genera Wolinella or Campylobacter despite phenotypic similarities. On the basis of our results and DNA-rRNA hybridization studies by other authors, we established the new genus Sulfurospirillum for the freeliving Campylobacter-like bacteria “Spirillum” 5175 and “Campylobacter spec.” DSM 806. Strain “Spirillum” 5175 is described as the type strain of the new genus and species Sulfurospirillum deleyianum.
