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1.
Abstract The formate oxidizing capacity of Wolinella recta ATCC 33238 was studied in relation to growth under anaerobic and microaerobic conditions. Three distinct activities could be recognized: (a) cyanide-insensitive H2O2-producing oxidation of formate; (b) peroxidation of formate (H2O2-consuming); (c) oxidation of formate via an electron transport chain with oxygen as the electron acceptor. The contribution of these different formate oxidizing components during the growth of W. recta was dependent on the extent of aeration. It is suggested that due to the relative increase in overall H2O2 formation at higher oxygen tensions growth of W. recta appears possible only under anaerobic and microaerobic conditions.  相似文献   

2.
Lipopolysaccharide (LPS) was isolated and purified from Wolinella recta ATCC 33238 by the phenol-water procedure and RNAase treatment. The sugar components of the LPS were rhamnose, mannose, glucose, heptose, 2-keto-3-deoxyoctonate (KDO) (3-deoxy-D-manno-octulosonate) and glucosamine. The degraded polysaccharide prepared from LPS by mild acid hydrolysis was fractionated by Sephadex G-50 gel chromatography into three fractions: (1) a high-molecular-mass fraction, eluting just behind the void volume, consisting of a long chain of rhamnose (22 mols per 3 mols of heptose residue) with attached core oligosaccharide; (2) a core oligosaccharide containing heptose, glucose and KDO, substituted with a short side chain of rhamnose; (3) a low-molecular-mass fraction containing KDO and phosphate. The main fatty acids of the lipid A were C12:0, C14:0, 3-OH-C14:0 and 3-OH-C16:0. The biological activities of the LPS were similar to those of Salmonella typhimurium LPS in activation of the clotting enzyme of Limulus amoebocytes, the Schwartzman reaction and mitogenicity for murine lymphocytes, although all the biological activities of lipid A were lower than those of intact LPS.  相似文献   

3.
DMSO respiration by the anaerobic rumen bacterium Wolinella succinogenes   总被引:1,自引:0,他引:1  
The anaerobic rumen bacterium Wolinella succinogenes was able to grow by respiration with dimethylsulphoxide (DMSO) as electron acceptor and formate or H2 as electron donors. The growth yield amounted to 6.7 g and 6.4 g dry cells/mol DMSO with formate or H2 as the donors, respectively. This suggested an ATP yield of about 0.7 mol ATP/mol DMSO. Cell homogenates and the membrane fraction contained DMSO reductase activity with a high K m (43 mM) for DMSO. The electron transport from H2 to DMSO in the membranes was inhibited by 2-(heptyl)-4-hydroxyquinoline N-oxide, indicating the participation of menaquinone. Formation of DMSO reductase activity occurred only during growth on DMSO, presence of other electron acceptors (fumarate, nitrate, nitrite, N2O, and sulphur) repressed the DMSO reductase activity. DMSO can therefore be used by W. succinogenes as an acceptor for phosphorylative electron transport, but other electron acceptors are used preferentially.Abbreviations DMN 2,3-Dimethyl-1,4-naphthoquinone - DMNH 2 Reduced DMN - DMS Dimethylsulphide (CH3)2S - DMSO Dimethylsulphoxide (CH3)2SO - HQNO 2-(Heptyl)-4-hydroxyquinoline-N-oxide - TMAO Trimethylamine-N-oxide - Y s Growth yield for substrate S  相似文献   

4.
In Wolinella succinogenes ATP synthesis and consequently bacterial growth can be driven by the reduction of either nitrate (E0=+0.42 V), nitrite (E0=+0.36 V), fumarate (E0=+0.03 V) or sulphur (E0=-0.27 V) with formate as the electron donor. Bacteria growing in the presence of nitrate and fumarate were found to reduce both acceptors simultaneously, while the reduction of both nitrate and fumarate is blocked during growth with sulphur. These observations were paralleled by the presence and absence of the corresponding bacterial reductase activities. Using a specific antiserum, fumarate reductase was shown to be present in bacteria grown with fumarate and nitrate, and to be nearly absent from bacteria grown in the presence of sulphur. The contents of polysulphide reductase, too, corresponded to the enzyme activities found in the bacteria. This suggests that the activities of anaerobic respiration are regulated at the biosynthetic level in W. succinogenes. Thus nitrate and fumarate reduction are repressed by the most electronegative acceptor of anacrobic respiration, sulphur. By contrast, in Escherichia coli a similar effect is exerted by the most electropositive acceptor, O2. W. succinogenes also differs from E. coli in that fumarate reductase is not repressed by nitrate.Abbreviations BV benzyl viologen - DMN 2,3-dimethyl-1,4-naphthoquinone - DMSO dimethylsulfoxide - TMAO trimethylamine-N-oxide  相似文献   

5.
6.
During growth with fumarate as the terminal electron transport acceptor and either formate or sulfide as the electron donor, Wolinella succinogenes induced a peri-plasmic protein (54 kDa) that reacted with an antiserum raised against the periplasmic fumarate reductase (Fcc) of Shewanella putrefaciens. However, the periplasmic cell fraction of W. succinogenes did not catalyze fumarate reduction with viologen radicals. W. succinogenes grown with polysulfide instead of fumarate contained much less (< 10%) of the 54-kDa antigen, and the antigen was not detectable in nitrate-grown bacteria. The antigen was most likely encoded by the fccA gene of W. succinogenes. The antigen was absent from a ΔfccABC mutant, and its size is close to that of the protein predicted by fccA. The fccA gene probably encodes a pre-protein carrying an N-terminal signal peptide. The sequence of the mature FccA (481 residues, 52.4 kDa) is similar (31% identity) to that of the C-terminal part (450 residues) of S. putrefaciens fumarate reductase. As indicated by Northern blot analysis, fccA is cotranscribed with fccB and fccC. The proteins predicted from the fccB and fccC gene sequences represent tetraheme cytochromes c. FccB is similar to the N-terminal part (150 residues) of S. putrefaciens fumarate reductase, while FccC resembles the tetraheme cytochromes c of the NirT/NapC family. The ΔfccABC mutant of W. succinogenes grew with fumarate and formate or sulfide, suggesting that the deleted proteins were not required for fumarate respiration with either electron donor. Received: 26 September 1997 / Accepted: 8 December  相似文献   

7.
Pterin derivatives were extracted from formate dehydrogenase and from polysulfide reductase of Wolinella succinogenes and converted to 6-carboxypterin. The amounts of 6-carboxypterin were consisted with the molybdenum content of the enzymes. The bis(carboxamidomethyl) derivatives of the cofactors showed absorption spectra that were identical with that of the corresponding molybdopterin guanine dinucleotide derivative (cam MGD). After hydrolysis of the derivatives with nucleotide pyrophosphatase in the presence of alkaline phosphatase, guanosine was formed together with a compound showing the properties of dephospho-bis(carboxamidomethyl)-molybdopterin. It is conluded that both formate dehydrogenase and polysulfide reductase of W. succinogenes contain molybdopterin guanine dinucleotide.Abbreviations MPT molybdopterin - MGD molybdopterin guanine dinucleotide - cam MPT bis(carboxyamidomethyl)-molybdopterin - cam MGD bis(carboxyamidomethyl)-molybdopterin guanine dinucleotide  相似文献   

8.
Wolinella succinogenes grown on formate and elemental sulphur was found to use the polysulphide derivatives 2,2-tetrathiobispropionate (R2S4) or pentathionate (S5O 6 = ) as acceptors for formate oxidation. The specific activities of formate oxidation with these acceptors were similar to those with elemental sulphur. The main reaction products of R2S4 reduction were 2,2-dithiobispropionate (R2S2) and sulphide. Pentathionate was converted to thiosulphate and some elemental sulphur. The electrochemical proton potential across the cytoplasmic membrane of the bacterium was measured in the steady state of electron transport from formate to R2S4. The electrical proportion () of the determined through the distribution of labeled tetraphenylphosphonium cation was obtained as 0.17 Volt. The was zero, when a protonophore was present. The pH-difference across the membrane was negligible. Thus the generated by sulphur respiration is close to that measured earlier with fumarate as the terminal acceptor of electron transport.Abbreviations DMO 5,5-dimethyloxazolidine-2,4-dione - R2Sn (n=2–5) 2,2-polythiobispropionate - TTFB 4,5,6,7-tetrachloro-2-trifluoromethylbenzimidazol - TPP tetraphenylphosphonium cation  相似文献   

9.
Wolinella succinogenes was found to grow on H2S plus fumarate with the formation of elemental sulfur and succinate. The growth rate was 0.18 h-1 (t d=3.8 h) and the growth yield was estimated to be 6.0 g per mol fumarate used. Growth also occurred on formate plus elemental sulfur; the products formed were H2S and CO2. The growth rate and estimated growth yield were 0.58 h-1 (t d=1.2 h) and 3.5 g per mol formate used, respectively. These results suggest that certain chemotrophic anaerobes may be involved in both the formation and reduction of sulfur.  相似文献   

10.
FC3-10 is a Klebsiella spp. specific bacteriophage isolated on a rough mutant (strain KT707, chemotype Rd) of K. pneumoniae C3. The bacteriophage receptor for this phage was shown to be the low-molecular mass lipopolysaccharide (LPS) fraction (LPS-core oligosaccharides), specifically the heptose content of the LPS inner-core. This is the first phage isolated on Klebsiella, the receptor for which is the LPS-core. This phage was unable to plate on Salmonella typhimurium LPS mutants with chemotypes Rd2 or Re showing incomplete or no heptose content on their LPS-core, respectively. Spontaneous phage-resistant mutants from different Klebsiella strains were deep-rough LPS mutants or encapsulated revertants from unencapsulated mutant strains.  相似文献   

11.
A Δsud deletion mutant of Wolinella succinogenes that lacked the periplasmic sulfide dehydrogenase (Sud) was constructed using homologous recombination. The mutant grew with sulfide and fumarate, indicating that Sud was not a component of the electron transport chain that catalyzed fumarate respiration with sulfide as an electron donor. Likewise, growth with formate and either polysulfide or sulfur was not affected by the deletion. Removal of Sud from wild-type W. succinogenes by spheroplast formation did not decrease the activity of electron transport to polysulfide. The Δpsr deletion mutant that lacks polysulfide reductase (Psr) grew by fumarate respiration with sulfide as an electron donor, indicating that Psr is not required for this activity. Received: 31 August 1995 / Accepted: 25 October 1995  相似文献   

12.
Wolinella succinogenes can grow at the expense of sulphur reduction by formate. The enzymes involved in the catalysis of this catabolic reaction have been investigated. From the results the following conclusions are drawn: 1. The enzyme isolated as a sulphide dehydrogenase from the cytoplasmic membrane of W. succinogenes is the functional sulphur reductase that operates in the electron transport from formate to sulphur. 2. The enzyme (Mr 200,000) consists essentially of one type of subunit with the Mr 85,000 and contains equal amounts of free iron and sulphide (120 mol/g protein), but no heme. It represents the first functional sulphur reductase ever isolated. 3. The electron transport chain catalyzing sulphur reduction by formate consists merely of formate dehydrogenase and sulphur reductase. A lipophilic quinone which mediates the transfer of electrons between enzymes in other chains, is apparently not involved. This is the first known example of a phosphorylative electron transport chain that operates without a quinone. 4. The same formate dehydrogenase appears to operate in the electron transport both with sulphur and with fumarate as the terminal electron acceptor in W. succinogenes.Abbreviations DMN 2,3-Dimethyl-1,4-naphthoquinone - DTT dithiothreitol - MK menaquinone (vitamin K2) - PMSF phenylmethane sulfonylfluoride - Tricine N-[2-hydroxy-1,1-bis(hydroxymethyl)ethyl]-glycine - Tea triethanolamine - Hepes 4-(2-hydroxyethyl)-1-piperazineethane sulfonate Dedicated to Professor F. Schneider (Philipps-Universität Marburg) on the occasion of his 60th birthday  相似文献   

13.
Wolinella succinogenes grows by anaerobic respiration with formate and polysulfide. Polysulfide forms spontaneously from sulfur and sulfide. Here we report that this eubacterium also grows with formate and elemental sulfur under conditions that do not allow polysulfide formation. With the appropriate amount of Fe2+ added to the medium, the concentration of polysulfide was calculated to be 0.4 nM, which is 1/400th of the concentration that of dissolved elemental sulfur. At commensurable growth rates, the growth yield with sulfur was one quarter of that with polysulfide as electron acceptor. The same low growth yield either with sulfur or with polysulfide as electron acceptor was measured for a Δpsr mutant that lacks the genes encoding polysulfide reductase (Psr). Received: 8 June 1995 / Accepted: 12 September 1995  相似文献   

14.
During their journey through the oviductal pars recta, the vitelline envelope (VE) of Bufo arenarum oocytes encounter structural alterations that make them sensitive to attack by sperm lysin and thus to penetration by sperm cells. The role of pars recta (PR) on the specificity of fertilization between amphibians was analyzed by conditioning Bufo arenarum oocytes with either homologous PR extract (PRE) or Leptodactylus chaquencis PRE. The oocytes were thereafter exposed to sperm lysin preparations from both species. Lysis of the VE only took place when the oocytes were exposed to the homologous PRE. The pattern of protein composition of PRE of these species was strikingly different as shown by Coomassie blue staining of SDS-PAGE. Moreover, antibodies against PR fluid (PRF) of Bufo arenarum produced seven bands of immunoprecipitation in electrophoresed homologous PRE and only one faint band in Leptodactylus chaquencis PRE. Here we show that: (i) the biological activity of PR from Bufo arenarum and Leptodactylus chaquencis over the VE of Bufo arenarum oocytes is species-specific; (ii) this specificity seems to be based in differences in protein structure, which was indicated by the fact that proteins from PRE of Leptodactylus chaquencis and Bufo arenarum were antigenically distinct; (iii) the specificity was solely related to PR activity and not to sperm lysin activity since sperm lysin preparations from both species showed comparable activity.  相似文献   

15.
The 16S ribosomal RNA of Wolinella succinogenes ATCC29543 was analyzed by the RNase T1 oligonucleotide cataloguing approach. In contrast to its present classification, W. succinogenes is related neither to members of the genus Bacteroides nor to any other genus of the family Bacteroidaceae. As derived from the similarity coefficients (SAB values) calculated on the basis of more than 350 eubacterial species, W. succinogenes appears to be a distantly related member of the division of purple photosynthetic bacteria and their relatives; however, SAB values do not indicate that this species is preferentially related to any representative of the 4 subdivisions.  相似文献   

16.
The linkage between the enzyme system catalysing formate hydrogenlyase and reductases involved in anaerobic respiration in intact cells of anaerobically grown Proteus mirabilis was studied. Reduction of nitrate and fumarate by molecular hydrogen or formate was possible under all growth conditions; reduction of tetrathionate and thiosulphate occurred only in cells harvested at late growth phase from a pH-regulated batch culture and not in cells harvested at early growth phase or in cells grown in pH-auxostat culture. Under all conditions, cells possessed the enzyme tetrathionate reductase. We conclude that linkage between tetrathionate reductase (catalysing also reduction of thiosulphate) and the formate hydrogenlyase chain is dependent on growth conditions. During reduction of high-potential oxidants such as fumarate, tetrathionate (when possible) or the artificial electron acceptor methylene blue by formate, there was no simultaneous H2 evolution due to the formate hydrogenlyase reaction. H2 production started only after complete reduction of methylene blue or fumarate, in the case of methylene blue after a lag phase without gas production. In preparations with a low fumarate reduction activity this was accompanied by an acceleration in CO2 production. During reduction of thiosulphate (a low-potential oxidant) or of tetrathionate in the presence of benzyl viologen (a low-potential mediator) by formate, H2 was evolved simultaneously. From this we conclude that formate hydrogenlyase is regulated by a factor that responds to the redox state of any electron acceptor couple present such that lyase activity is blocked when the acceptor couple is oxidised to too great an extent.  相似文献   

17.
18.
Wolinella succinogenes grown with nitrate as terminal electron acceptor contains two nitrite reductases as measured with the donor viologen radical, one in the cytoplasm and the other integrated in the cytoplasmic membrane. The fumarate-grown bacteria contain only the membraneous species.The isolated membraneous enzyme consists of a single polypeptide chain (M r 63,000) carrying 4 hemeC groups and probably an iron-sulphur cluster as prosthetic groups. The enzyme amounts to about 1% of the total membrane protein.The isolated enzyme catalyses the reduction of nitrite to ammonium without accumulation of significant amounts of intermediates or alternative products. The Michaelis constant for nitrite was 0.1 mM and the turnover number of the hemeC 1.5 · 105 electrons per min at 37°C.The viologen-reactive site of the enzyme in the membrane is oriented towards the cytoplasm. When the isolated enzyme is incorporated into liposomes, the viologen-as well as the nitrite-reactive site is exposed to thooutside.The cytoplasmic membrane contains a second hemeC protein (M r 22,000) which may represent a cytochrome c.Abbreviations NQNO 2-(n-nonyl)-4-hydroxyquinoline-N-oxide - MES 2-(N-morpholino)ethanesulfonate - MOPS 3-(N-morpholino)propanesulfonate - HEPES N-2-Hydroxyethylpiperazine-N-2-ethanesulfonate - TES N-tris(hydroxymethyl)methyl-2-aminoethanesulfonate - MK menaquinone  相似文献   

19.
A novel methanotrophic gammaproteobacterium, strain KoM1, was isolated from the profundal sediment of Lake Constance after initial enrichment in opposing gradients of methane and oxygen. Strain KoM1 grows on methane or methanol as its sole source of carbon and energy. It is a Gram-negative methanotroph, often expressing red pigmentation. Cells are short rods and occur sometimes in pairs or short chains. Strain KoM1 grows preferably at reduced oxygen concentrations (pO2 = 0.05–0.1 bar). It can fix nitrogen, and grows at neutral pH and at temperatures between 4 and 30 °C. Phylogenetically, the closest relatives are Methylovulum miyakonense and Methylosoma difficile showing 91% 16S rRNA gene sequence identity. The only respiratory quinone is ubiquinone Q8; the main polar lipids are phosphatidyl ethanolamine and phosphatidyl glycerol. The major cellular fatty acids are summed feature 3 (presumably C16:1ω7c) and C16:1ω5c, and the G + C content of the DNA is 47.7 mol%. Strain KoM1 is described as the type strain of a novel species within a new genus, Methyloglobulus morosus gen. nov., sp. nov.  相似文献   

20.
Abstract A genomic DNA library of Campylobacter rectus (Wolinella recta) ATCC 33238 was constructed using bacteriophage lambda EMBL3 as a vector. One clone expressing the S-layer protein was identified immunologically with the antiserum to the S-layer protein of C. rectus ATCC 33238. Western immunoblotting using monoclonal antibodies directed against the S-layer protein showed a single blot of recombinant protein at 150 kDa, suggesting that this clone contained the entire coding region of the S-layer protein gene. Additionally, the S-layer protein gene was subcloned into plasmid vector pUC18. Southern hybridization revealed that the S-layer protein gene was present on the chromosome of C. rectus as a single-copy gene, and that there were minor heterogeneities among the S-layer protein genes of clinical isolates. Moreover, a spontaneous stable mutant strain, which has no S-layer expression, also conserved the full-length gene of the S-layer protein.  相似文献   

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