Publications

refined structure of cytochrome c3 at 1.8 a resolution.	the structure of cytochrome c3 from the sulfate-reducing bacterium desulfovibrio vulgaris miyazaki has been successfully refined at 1.8 a resolution. the crystallographic r factor is 0.176 for 9907 significant reflections. the isotropic temperature factors of individual atoms were refined and a total of 47 water molecules located on the difference map were incorporated in the refinement. the four heme groups are closely packed, with adjacent pairs of heme planes being nearly perpendicular to eac ...	1984	6319712
molybdenum exafs of the desulfovibrio gigas mo(2fe-2s) protein--structural similarity to "desulfo" xanthine dehydrogenase.	the molybdenum exafs of the mo(2fe-2s) protein from desulfovibrio gigas has been examined using fluorescence detection and synchrotron radiation. in the oxidized form the molybdenum environment is found to contain two terminal oxo groups and two long (2.47 a) mo-s bonds. evidence was also found for an oxygen or nitrogen donor ligand at 1.90 a. addition of dithionite to the oxidized enzyme results in loss of a terminal oxo group, perhaps due to protonation. in addition, a 0.1 a contraction in the ...	1984	6325597
application of hydrophobic chromatography to the large scale purification of desulfovibrio desulfuricans cytochrome c3.	hydrophobic chromatography on phenyl-sepharose was employed for large scale purification of cytochrome c3 from desulfovibrio desulfuricans. this chromatographic procedure minimizes operational volumes and eliminates the lengthy dialysis ordinarily used to remove large amounts of salts. pure cytochrome c3 was obtained after one additional purification by ion-exchange chromatography.	1984	6326080
desulfovibrio vulgaris hydrogenase: a nonheme iron enzyme lacking nickel that exhibits anomalous epr and mössbauer spectra.	a purification procedure for the periplasmic hydrogenase from desulfovibrio vulgaris ( hildenborough , national collection of industrial bacteria 8303) is reported. the purified hydrogenase has a specific activity of 4800 units per mg of protein. plasma emission studies reveal that this highly active hydrogenase is free of nickel and contains 11 (+/- 1) nonheme iron atoms per molecule. a combined epr and mössbauer study indicates that the majority of the iron atoms are bound in the form of iron- ...	1984	6328525
correlations studies between structural and redox properties of cytochromes c3.	individual redox potential values are determined for different cytochromes c3. these polyhaemic cytochromes can be divided into two groups: one characterized by only one marked reduction step, the other one giving at least two well-marked reduction steps corresponding to redox potential values ranging from - 0.120 to - 0.400 v. correlations between potential values and structural data are discussed.	1984	6329165
characterization of three iron ferredoxins by microwave power saturation.	we have measured the electronic spin lattice relaxation time t1 in the temperature range 4 k-10 k, by microwave power saturation on the 3fe ferredoxins from desulfovibrio gigas and azotobacter vinelandii. the comparison with the results previously obtained on other iron sulfur proteins emphasizes the particularly fast relaxing properties of the e.p.r. signal in 3fe ferredoxins. these results support the models of the active site which predict very low lying excited levels.	1984	6329322
electron transfer mechanism and interaction studies between cytochrome c3 and ferredoxin.	ferredoxin, cytochrome c3 and hydrogenase are specific partners of the sulfate reduction pathway of desulfovibrio desulfuricans norway and might be exemplary for electron exchange mechanism studies. cytochrome c3 contains four low redox potential haems for 13 000 molecular weight. two ferredoxins isolated from the same bacteria are dimers of 6 000 molecular weight per subunit (ferredoxin i: one (4 fe-4s) cluster per subunit, ferredoxin ii: two (4 fe-4 s) clusters per subunit). the amino acid seq ...	1984	6329323
nmr studies of electron transfer mechanisms in a protein with interacting redox centres: desulfovibrio gigas cytochrome c3.	the proton nmr spectra of the tetrahaem cytochrome c3 from desulfovibrio gigas were examined while varying the ph and the redox potential. the analysis of the nmr reoxidation pattern was based on a model for the electron distribution between the four haems that takes into account haem-haem redox interactions. the intramolecular electron exchange is fast on the nmr time scale (larger than 10(5) s-1). the nmr data concerning the ph dependence of the chemical shift of haem methyl resonances in diff ...	1984	6329752
interconversion from 3fe into 4fe clusters in the presence of desulfovibrio gigas cell extracts.	desulfovibrio gigas ferredoxin ii (fdii) contains a single 3fe cluster [huynh, b.h., moura, j.j.g., moura, i., kent, t.a., legall, j., xavier, a.v., and münck, e. (1980) j. biol. chem. 255, 3242-3244]. in the oxidized state the protein exhibits an intense electron paramagnetic resonance (epr) signal at g = 2.02. upon one-electron reduction the center becomes epr silent. in the presence of d. gigas crude cell extracts, devoid of acidic electron carriers and supplemented with pyruvate and fdii, an ...	1984	6329755
immobilization of isolated and cellular hydrogenase of d. desulfuricans in radiation-polymerized polyacrylamides.	purified hydrogenase from desulfovibrio desulfuricans was immobilized either by entrapment or absorption onto porous neutral and charged acrylamide beads. surface absorption and crosslinking on the beads resulted in a high hydrogenase activity and a good immobilization coefficient compared to the enzyme and whole cells entrapped in the same matrix. maximum enzyme activity (citrate-phosphate buffer) was shifted to ph 6.5 upon immobilization in contrast to 6.0 for the free enzyme and the range of ...	1984	6383215
reactivation of the hydrogenase from desulfovibrio gigas by hydrogen. influence of redox potential.	the specific activity of the periplasmic hydrogenase from desulfovibrio gigas is increased approximately 10-fold in the h2 utilization assay with benzyl viologen by several hours of incubation under an atmosphere of h2. after a variable lag phase during which residual traces of o2 are removed, the reversible activation is exponential. the extent of activation is dependent on ph and the redox potential of the incubation medium. a tentative model based on the existence of a monoelectronic redox ce ...	1984	6384213
hydrogen-using bacteria in a methanogenic acetate enrichment culture.	in a study of the anaerobic utilization of acetate, an enrichment culture of sewage sludge organisms was initiated with calcium acetate as the sole carbon and energy source. a mixed bacterial population became established from which 14 anaerobic species were isolated. two of the isolates were methanogenic bacteria but only one of these, methanosarcina barkeri, utilised acetate as an energy source in axenic culture. the other methanogenic isolate, a methanobacterium sp., utilised h2/co2 but not a ...	1984	6423605
examination of protein sequence homologies: i. eleven escherichia coli l7/l12-type ribosomal "a" protein sequences from eubacteria and chloroplast.	seven complete and four partial sequences of escherichia coli l7/l12-type ribosomal "a" proteins obtained from various bacteria (e. coli, bacillus subtilis, micrococcus lysodeikticus, rhodopseudomonas spheroides, desulfovibrio vulgaris, streptomyces griseus, bacillus stearothermophilus, clostridium pasteurianum, arthrobacter glacialis, and vibrio costicola) and spinach chloroplast have been reexamined using a computer program that searches for homologous tertiary structures. comparison matrices ...	1984	6443314
electrochemical transducers for the measurement of biological compounds.		1984	6471821
physiological function of hydrogen metabolism during growth of sulfidogenic bacteria on organic substrates.	desulfovibrio vulgaris madison and thermodesulfobacterium commune contained functionally distinct hydrogenase activities, one which exchanged 3h2 into 3h2o and was inhibited by carbon monoxide and a second activity which produced h2 in the presence of co. cell suspensions of d. vulgaris used either lactate, pyruvate, or co as the electron donor for h2 production in the absence of sulfate. both sulfidogenic species produced and consumed hydrogen as a trace gas during growth on lactate or pyruvate ...	1984	6480553
crystallization and preliminary x-ray diffraction study of the 3-fe ferredoxin ii from the bacterium desulfovibrio gigas.	the 3-fe ferredoxin (fdii) from the bacterium desulfovibrio gigas has been crystallized at ph 5.0 and 23 degrees c in two different crystal forms. one form is monoclinic, space group c2, with unit cell parameters a = 40.78 a, b = 44.98 a, c = 26.47 a, beta = 104.6 degrees, and one monomer of the fdii tetramer per asymmetric unit. the molecule can be either the monomer of molecular weight 6400 or a dimer of twice this molecular weight with 2-fold symmetry coincident with the 2-fold axis of the cr ...	1984	6502709
characterization of the fe-s cluster in aconitase using low temperature magnetic circular dichroism spectroscopy.	beef heart aconitase has been studied by low temperature magnetic circular dichroism (mcd) spectroscopy in the wavelength region 300 to 1900 nm. together with parallel electron paramagnetic resonance and activity measurements, these data enable correlations between fe-s cluster-type and enzymic activity in aconitase. in samples not exposed to extraneous fe, the fe-s cluster in aconitase exhibits the characteristic properties of a 3fe center in both the as isolated and dithionite-reduced states. ...	1984	6698964
methanogenesis from sucrose by defined immobilized consortia.	a bacterial consortium capable of sucrose degradation primarily to ch(4) and co(2) was constructed, with acetate as the key methanogenic precursor. in addition, the effect of agar immobilization on the activity of the consortium was determined. the primary fermentative organism, escherichia coli, produced acetate, formate, h(2), and co(2) (known substrates for methanogens), as well as ethanol and lactate, compounds that are not substrates for methanogens. oxidation of the nonmethanogenic substra ...	1984	16346452
competition for sulfate and ethanol among desulfobacter, desulfobulbus, and desulfovibrio species isolated from intertidal sediments.	competition for sulfate and ethanol among desulfobacter, desulfobulbus, and desulfovibrio species isolated from estuarine sediments was studied in energy-limited chemostats. desulfovibrio baculatus was the most successful competitor for limiting amounts of sulfate and ethanol, followed by desulfobulbus propionicus. the success of desulfovibrio baculatus was dependent on the availability of sufficient iron. of the three species studied, desulfobacter postgatei was the least successful competitor ...	1984	16346474
isolation and partial characterization of bacteria in an anaerobic consortium that mineralizes 3-chlorobenzoic acid.	a methanogenic consortium able to use 3-chlorobenzoic acid as its sole energy and carbon source was enriched from anaerobic sewage sludge. seven bacteria were isolated from the consortium in mono- or coculture. they included: one dechlorinating bacterium (strain dcb-1), one benzoate-oxidizing bacterium (strain bz-2), two butyrate-oxidizing bacteria (strains sf-1 and nsf-2), two h(2)-consuming methanogens (methanospirillum hungatei pm-1 and methanobacterium sp. strain pm-2), and a sulfate-reducin ...	1984	16346648
methanogenesis from choline by a coculture of desulfovibrio sp. and methanosarcina barkeri.	a sulfate-reducing vibrio was isolated from a methanogenic enrichment with choline as the sole added organic substrate. this organism was identified as a member of the genus desulfovibrio and was designated desulfovibrio strain g1. in a defined medium devoid of sulfate, a pure culture of desulfovibrio strain g1 fermented choline to trimethylamine, acetate, and ethanol. in the presence of sulfate, more acetate and less ethanol were formed from choline than in the absence of sulfate. when grown in ...	1983	16346162
radioassay for hydrogenase activity in viable cells and documentation of aerobic hydrogen-consuming bacteria living in extreme environments.	an isotopic tracer assay based on the hydrogenase-dependent formation of tritiated water from tritium gas was developed for in life analysis of microbial hydrogen transformation. this method allowed detection of bacterial hydrogen metabolism in pure cultures or in natural samples obtained from aquatic ecosystems. a differentiation between chemical-biological and aerobic-anaerobic hydrogen metabolism was established by variation of the experimental incubation temperature or by addition of selecti ...	1983	16346288
energetics of growth of a defined mixed culture of desulfovibrio vulgaris and methanosarcina barkeri: interspecies hydrogen transfer in batch and continuous cultures.	interspecies hydrogen transfer was studied in desulfovibrio vulgaris-methanosarcina barkeri mixed cultures. experiments were performed under batch and continuous growth culture conditions. lactate or pyruvate was used as an energy source. in batch culture and after 30 days of simultaneous incubation, these organisms were found to yield 1.5 mol of methane and 1.5 mol of carbon dioxide per mol of lactate fermented. when m. barkeri served as the hydrogen acceptor, growth yields of d. vulgaris were ...	1983	16346421
growth of a strictly anaerobic bacterium on furfural (2-furaldehyde).	a strictly anaerobic bacterium was isolated from a continuous fermentor culture which converted the organic constituents of sulfite evaporator condensate to methane and carbon dioxide. furfural is one of the major components of this condensate. this furfural isolate could degrade furfural as the sole source of carbon and energy in a defined mineral-vitamin-sulfate medium. acetic acid was the major fermentation product. this organism could also use ethanol, lactate, pyruvate, or fumarate and cont ...	1983	16346423
semi-micro methods for analysis of labile sulfide and of labile sulfide plus sulfane sulfur in unusually stable iron-sulfur proteins.	details are provided for a reproducible procedure for determination of labile sulfide in iron-sulfur (fe-s) proteins in the range of 1 to 3 nmol. analyses are also presented on the most stable fe-s protein so far reported. in this case denaturation with guanidine.hcl was used in the presence of dithiothreitol. the values obtained then also include any sulfane sulfur (s0) present.	1983	6614472
crystallographic study of rubredoxin from the bacterium desulfovibrio desulfuricans strain 27774.	rubredoxin from desulfovibrio desulfuricans (strain 27774) has been isolated and crystallized. preliminary amino acid and crystallographic analyses indicate that this rubredoxin is the smallest rubredoxin isolated so far. the amino acid analysis indicates that the molecule is composed of 45 to 48 residues and contains histidine, which is unusual for rubredoxins from anaerobic bacteria. the x-ray diffraction pattern from these crystals reveals they belong to space group p1 with cell parameters: a ...	1983	6644818
glutathione reductase in evolution.	the disulfide reducing activities of gssg-and coassg-reductases were measured on partially purified extracts from a variety of prokaryotes and eukaryotes. glutathione-reductase was found in varying amounts in all eukaryotes and prokaryotes, used in this study, with the exception of the two strict anaerobes clostridium tartarivorum and desulfovibrio vulgaris, and the two primitive archaebacteria methanosarcina barkeri and halobacterium halobium. coassg-reductase was found in some eukaryotes and p ...	1983	6644831
energy coupling to nitrite respiration in the sulfate-reducing bacterium desulfovibrio gigas.	by use of a membrane fraction prepared from desulfovibrio gigas grown in a lactate-sulfate medium, synthesis of atp was demonstrated to be coupled to the oxidation of molecular hydrogen and reduction of either nitrite or hydroxylamine. this phosphorylation was uncoupled from electron transport by pentachlorophenol, methyl viologen, and gramicidin, but not by oligomycin. the extrusion of protons from the cells was shown to be coupled to the hydrogen-nitrite respiratory system, and, assuming the l ...	1983	6822477
characterization of a new type of dissimilatory sulfite reductase present in thermodesulfobacterium commune.	a new type of dissimilatory bisulfite reductase, desulfofuscidin, was isolated from the nonsporeforming thermophilic sulfate-reducing microorganism thermodesulfobacterium commune. the molecular weight of the enzyme was estimated at 167,000 by sedimentation equilibrium, and the protein was pure by both disc electrophoresis and ultracentrifugation. the bisulfite reductase was a tetramer and had two types of subunits with an alpha(2)beta(2) structure and an individual molecular weight of 47,000. th ...	1983	6826522
[effect of carbon monoxide on the growth of sulfate-reducing bacteria and their oxidation of this substrate].	the effect of carbon monoxide on the growth of six strains of sulfatee-reducing bacteria have been studied as well as the ability of bacterial suspensions and extracts to oxidize co. it was shown that sulfate-reducing bacteria possess a comparably high resistance to carbon monoxide. there are difference in the sensitivity of certain species and strains of sulphat-reducing bacteria to the content of co in the gas phase. the cell suspensions and extracts are capable of oxidizing 100% co in gaseous ...	1983	6838935
raman spectra of flavin bound in flavodoxins and in other flavoproteins. evidence for structural variations in the flavin-binding region.	the resonance coherent anti-stokes raman scattering (cars) spectra for a number of flavoproteins are found to be fingerprints for the particular type of flavoprotein. one group studied were the bacterial flavodoxins: desulfovibrio vulgaris, desulfovibrio desulfuricans, azotobacter vinelandii, megasphaera elsdenii, clostridium kluyverii and clostridium formicoaceticum. the other examples were the enzymes lactate monooxygenase and glucose oxidase. fmn complexed to vibrio harveyi luciferase, and a ...	1983	6840072
nonlinear estimation of monod growth kinetic parameters from a single substrate depletion curve.	monod growth kinetic parameters were estimated by fitting sigmoidal substrate depletion data to the integrated monod equation, using nonlinear least-squares analysis. when the initial substrate concentration was in the mixed-order region, nonlinear estimation of simulated data sets containing known measurement errors provided accurate estimates of the mu max, ks, and y values used to create these data. nonlinear regression analysis of sigmoidal substrate depletion data was also evaluated for h2- ...	1983	6870238
characterization of periplasmic hydrogenase from desulfovibrio vulgaris miyazaki k.	periplasmic hydrogenase [hydrogen:ferricytochrome c3 oxidoreductase, ec 1.12.2.1] from desulfovibrio vulgaris miyazaki k (mk) was purified to homogeneity. its chemical and immunological properties were examined and compared with those of other desulfovibrio hydrogenases. the pure enzyme showed a specific activity of 1,000 mumol h2 evolution min-1 (mg protein)-1. the enzyme had a molecular weight of 50,000 as estimated by gel filtration and consisted of a single polypeptide chain. the absorption ...	1983	6874662
preliminary crystallographic data on a ferredoxin from desulfovibrio desulfuricans (norway strain).	the ferredoxin (fd i) (mr2 x 6000, one (4 fe-4 s) cluster per subunit) from the sulphate-reducing bacteria desulfovibrio desulfuricans norway 4 has been crystallized. the space group is p4(2)32 with a = 71.8 a. the two monomers of the molecule are probably related by a dyad axis.	1983	6876178
energetics of growth of a defined mixed culture of desulfovibrio vulgaris and methanosarcina barkeri: maintenance energy coefficient of the sulfate-reducing organism in the absence and presence of its partner.	the maintenance energy coefficient of desulfovibrio vulgaris was studied by using a chemostat, with methanosarcina barkeri or sulfate as the electron acceptor; lithium lactate or sodium pyruvate served as the electron donor. the experiments showed that the growth energetics of d. vulgaris or m. barkeri were greatly affected by maintenance energy coefficients. when d. vulgaris grew on lactate or pyruvate medium with sulfate, these coefficients reached 4.40 and 2.80 mm g-1 h-1, respectively; on la ...	1983	6885720
primary structure of the two (4 fe-4 s) clusters ferredoxin from desulfovibrio desulfuricans (strain norway 4).	the primary structure of a ferredoxin isolated from d. desulfuricans norway strain, which we called ferredoxin ii (fd ii) has been elucidated. this ferredoxin is a dimer constituted of two identical subunits of molecular weight 6000. in ferredoxin ii two (4 fe-4 s) centers are present per subunit instead of one (fe-s) center as is the case for the other ferredoxins isolated from desulfovibrio and for fd i from the same organism. the comparison of amino-acid sequences shows that ferredoxin ii pre ...	1983	6403056
structure of oxidized flavodoxin from anacystis nidulans.	the structure of oxidized flavodoxin from the cyanobacterium anacystis nidulans has been determined at 2.5 a resolution with phases calculated from ethylmercury phosphate and dimercuriacetate derivatives. the determination of partial sequences, including a total of 85 residues, has assisted in the interpretation of the electron density. preliminary refinement of a partial model (1072 atoms) has reduced r to 0.349 for the 10.997 reflections between 2.0 and 5.0 a with 1 greater than 2 sigma. the p ...	1983	6406674
[utilization of carbon monoxide by bacteria of the genus desulfovibrio].		1983	6418781
kinetic properties of hydrogenase isolated from desulfovibrio vulgaris (hildenborough).	hydrogenase of desulfovibrio vulgaris shows nonlinear kinetics in hydrogen production with both the natural electron carrier, cytochrome c3, and the artificial donor, methyl viologen semiquinone. increasing concentrations of salt progressively inhibit the hydrogen production, as do increasing amounts of dimethylsulfoxide (me2so). hydrogen consumption activity does not change up to 30% (v/v) of me2so. preincubation in me2so up to 55% (v/v) does not affect the hydrogen uptake or production. the pr ...	1983	6339237
three-iron clusters in iron-sulfur proteins.	contents. 1. introduction and history. 2. characteristic spectroscopic features of 3fe clusters. 1. general considerations. 2. mössbauer spectroscopy. 3. magnetic circular dichroism (mcd) spectroscopy. 4. electron paramagnetic resonance (epr) spectroscopy. 5. resonance raman (rr) spectroscopy. 6. extended x-ray fine-structure (exafs) spectroscopy. 3. results of x-ray diffraction studies. 4. proteins containing or showing features characteristic of 3fe clusters 1. overview. 2. ferredoxin i of azo ...	1983	6342537
[microbiological synthesis of tetrapyrrole compounds].	this paper reviews publications on the biosynthesis of functional tetrapyrroles by microorganisms. emphasis is given to the structure of uroporphyrin iii methylated derivatives termed corriphyrins and their involvement in the formation of two groups of tetrapyrrole pigments--corrinoids and siroheme. current concepts concerning the final stages of the formation of the corrine ring and potential cobalt-free precursors of vitamin b12 are discussed. it is indicated that the data available may help e ...	1983	6344060
bidirectional measurement of hydrogenase activity by the ph-stat method.	the protons produced by the catalytic activity of hydrogenase in h2 evolution from dithionite-reduced methyl viologen or through benzyl viologen reduction by h2 gas are automatically titrated by a ph-stat device. this approach allows the measurement of hydrogenase activity and ensures the constancy of ph during the reaction in absence of buffers. kinetic assays and ph and temperature-dependence experiments with desulfovibrio gigas hydrogenase performed by this method basically confirm the result ...	1983	6351666
resonance raman studies of beef heart aconitase and a bacterial hydrogenase.	the resonance raman (rr) spectra of beef heart aconitase and of an air-stable hydrogenase from desulfuvibrio desulfuricans, as isolated, are characteristic of 3fe centers. activation of aconitase by fe(ii) addition converts the rr spectrum to one characteristic of [4fe-4s]2+ clusters. analytical data on aconitase, as isolated, confirms the recent finding (beinert, h., emptage, m. h., dreyer, j.-l., scott, r. a., hahn, j. e., hodgson, k. o., and thomson, a. j. (1983) proc. natl. acad. sci. u. s. ...	1983	6355093
desulfovibrio gigas hydrogenase: redox properties of the nickel and iron-sulfur centers.	below 30 k, oxidized desulfovibrio gigas hydrogenase presents an intense electron paramagnetic resonance (epr) signal centered at g = 2.02, typical of an iron-sulfur center. in addition a rhombic epr signal, attributed to ni(iii) species, is also observed [legall, j., ljungdahl, p., moura, i., peck, h.d., jr, xavier, a.v., moura, j.j.g., teixeira, m., huynh, b.h., and dervartanian, d.v. (1982) biochem. biophys. res. commun. 106, 610-616; and cammack, r., patil, d., aguirre, r., and hatchikian, e ...	1983	6297907
iron-sulfur stoichiometry and structure of iron-sulfur clusters in three-iron proteins: evidence for [3fe-4s] clusters.	beef heart aconitase contains 3fe clusters in its inactive and 4fe clusters in its active form. the fully active form can be restored from the inactive one by insertion of fe(2+), whereas s(2-) is not required. chemical analyses for iron and labile sulfide yield fe/s(2-) ratios of 0.66-0.74 for the inactive and 0.90-1.03 for the active form. sulfane sulfur (s(0)) was not detected. we propose on the basis of these data that the inactive form may arise from the active one by loss of one iron only ...	1983	6300839
purification and properties of the membrane-bound by hydrogenase from desulfovibrio desulfuricans.	the membrane-bound hydrogenase from the anaerobic sulphate-reducing bacterium desulfovibrio desulfuricans (norway strain) has been purified to homogeneity, with an overall 80-fold purification and a specific activity of 70 mumol of h2 evolved/min per mg of protein. the hydrogenase had a relative molecular mass of 58 000 as determined by gel filtration and was estimated to contain six iron atoms and six acid-labile sulphur groups per molecule. the absorption spectrum of the enzyme was characteris ...	1983	6303306
comparative studies of monohemic bacterial c-type cytochromes. redox and optical properties of desulfovibrio desulfuricans norway cytochrome c553(550) and pseudomonas aeruginosa cytochrome c551.	redox properties of cytochrome c553(550) from desulfovibrio desulfuricans norway (eo' = 0.04 + 0.02 v/nhe) and cytochrome c551 from p. aeruginosa (eo = 0.25 +/- 0.02 v/nhe) are compared with those of some monohemic c-type cytochromes. the pk value for the equilibrium between the ph-dependent forms of cytochrome c553(550) (pk = 10.3 +/- 0.1) has been also determined. it is to be noted that the difference between redox potentials can extend to nearly 250 mv, though the axial heme ligands are ident ...	1983	6307291
electron paramagnetic resonance and other properties of hydrogenases isolated from desulfovibrio vulgaris (strain hildenborough) and megasphaera elsdenii.	the hydrogenases of desulfovibrio vulgaris and megasphaera elsdenii are compared with respect to some of their physical properties. in addition to fe the only metal ions that are present in significant amounts are ni and cu. from cluster extrusion experiments it follows that the d. vulgaris enzyme contains three 4 fe-4s clusters, while m. elsdenii hydrogenase only releases part of its fe-s clusters. the resting d. vulgaris enzyme shows only a small 3 fe-xs type of epr signal (maximum 5% electron ...	1983	6311546
esr characteristics of sulfhydryl-containing peptide-nickel (iii) complexes: implication for nickel (iii) center of hydrogenases.	the ni(iii) complexes of n-mercaptoacetylglycyl-l-histidine and n-mercaptoacetylglycylglycylglycine clearly show the rhombic esr pattern and g-values similar to the ni(iii) chromophore of hydrogenases. the present results strongly suggest that the ni(iii) center of hydrogenases contains one cysteine sulfur coordination as equatorial ligand in a tetragonal geometry. in addition, axial nitrogen ligand and a sulfur-rich ni(iii) site as in an s4 donor set may be ruled out. indeed, the ni(iii) esr fe ...	1983	6313001
coordination of the heme iron in the low-potential cytochromes c-553 from desulfovibrio vulgaris and desulfovibrio desulfuricans. different chirality of the axially bound methionine in the oxidized and reduced states.	the coordination geometry at the heme iron of the cytochromes c-553 from desulfovibrio vulgaris and desulfovibrio desulfuricans was investigated by 1h-nuclear magnetic resonance and circular dichroism spectroscopy. individual assignments were obtained for heme c and the axial ligands. from studies of nuclear overhauser enhancements the axial histidine imidazole ring orientation relative to the heme group was found to coincide with other c-type cytochromes. in contrast, a new structure was observ ...	1983	6313059
amino acid sequence of cytochrome c-553 from desulfovibrio vulgaris miyazaki.	the complete amino acid sequence of cytochrome c-553 from desulfovibrio vulgaris miyazaki has been determined. the protein has a single polypeptide chain containing 79 amino acid residues and has the typical characteristics of small mitochondrial cytochromes. contrary to the expectation that the amino acid sequence of cytochrome c-553 from d. vulgaris miyazaki is closely related to that from d. vulgaris hildenborough, the two are not alike, except for the 20 nh2-terminal residues and the 4 carbo ...	1983	6313657
iron-sulphur cluster composition and redox properties of two ferredoxins from desulfovibrio desulfuricans norway strain.	two ferredoxins from desulfovibrio desulfuricans, norway strain, were investigated by epr spectroscopy. ferredoxin i appears to be a conventional [4fe-4s]2+;1+ ferredoxin, with a midpoint reduction potential of -374 mv at ph 8. ferredoxin ii when reduced, at first showed a more complex spectrum, indicating an interaction between two [4fe-4s] clusters, and probably, has two clusters per protein subunit. upon reductive titration ferredoxin ii changed to give a spectrum in which no intercluster int ...	1982	6279148
interconversions of [3fe-3s] and [4fe-4s] clusters. mössbauer and electron paramagnetic resonance studies of desulfovibrio gigas ferredoxin ii.		1982	6281263
activation, reduction and proton-deuterium exchange reaction of the periplasmic hydrogenase from desulfovibrio gigas in relation with the role of cytochrome c3.		1982	6282633
purification and characterization of cytochrome c3 (mr 26,000) isolated form desulfovibrio desulfuricans norway strain.		1982	6284155
the presence of redox-sensitive nickel in the periplasmic hydrogenase from desulfovibrio gigas.		1982	6285924
cytochrome c553 from desulfovibrio vulgaris: potentiometric characterization by optical and epr studies.		1982	6288033
ferredoxin from methanosarcina barkeri: evidence for the presence of a three-iron center.	methanosarcina barkeri ferredoxin was purified and characterized by electron paramagnetic resonance (epr) and mössbauer spectroscopy. the purification procedure included chromatographic steps on deae-cellulose and gel filtration. the isolated protein is unstable under aerobic conditions. the ferredoxin exhibits charge transfer bands at 283 nm and 405 nm with an absorption ratio a405/a283 = 0.73. its molecular weight has been estimated to be 20000-22000 by gel filtration chromatography. the nativ ...	1982	6290216
nmr redox studies of desulfovibrio vulgaris cytochrome c3. electron transfer mechanisms.	the 300-mhz proton nmr spectra of the tetrahaem cytochrome c3 from desulfovibrio vulgaris were examined while varying the ph and the redox potential. the analysis of the complete nmr reoxidation pattern was done taking into account all the 16 redox states that can be present in the redox titration of a tetra-redox-center molecule. a network of saturation transfer experiments performed at different oxidation stages, between the fully reduced and the fully oxidized states, allowed the observation ...	1982	6291937
crystal structure and electron transfer properties of cytochrome c3.	the crystal structure of cytochrome c3 from the sulfate-reducing bacteria desulfovibrio desulfuricans, norway strain, has been determined through the fitting of the recently completed primary structure to a 2.5 a resolution electron density map. the phase calculations were based on three mercurial derivatives; anomalous scattering data were used to refine the four heme iron positions. a preliminary refinement of the molecular model has led to a conventional crystallographic r factor of 34%. cyto ...	1982	6292223
a pulse-radiolysis study of cytochrome c3. kinetics of the reduction of cytochrome c3 by methyl viologen radicals and the characterisation of the redox properties of cytochrome c3 from desulfovibrio vulgaris (hildenborough).	1. pulse-radiolysis experiments were performed in the presence of methyl viologen and cytochrome c3. after the pulse, methyl viologen radicals are formed and the kinetics of these radicals with cytochrome c3 are studied, the reaction between cytochrome c3 and methyl viologen radicals (mv+) is diffusion controlled. the ionic strength dependence and the ph-dependence of this reaction were studied. from the ionic strength dependence (at ph 7.8) we found that the net charge of the fully oxidized cyt ...	1982	6293820
evidence for nickel and a three-iron center in the hydrogenase of desulfovibrio desulfuricans.	hydrogenase from desulfovibrio desulfuricans (atcc no. 27774) grown in unenriched and in enriched 61ni and 57fe media has been purified to apparent homogeneity. two fractions of enzymes with hydrogenase activity were separated and were termed hydrogenase i and hydrogenase ii. they were shown to have similar molecular weights (77,600 for hydrogenase i and 75,500 for hydrogenase ii), to be composed of two polypeptide chains, and to contain ni and non-heme iron. because of its higher specific activ ...	1982	6294073
unambiguous identification of the nickel epr signal in 61ni-enriched desulfovibrio gigas hydrogenase.		1982	6295382
biochemistry of dissimilatory sulphate reduction.	extensive information is available on the enzymology of respiratory sulphate reduction and the structure of electron transfer proteins isolated from the sulphate-reducing bacteria; however, it has not yet been possible to delineate satisfactorily the function of these electron transfer proteins in terms of the enzymes involved in respiratory sulphate reduction. new information about differences in pyrophosphate metabolism by desulfovibrio and desulfotomaculum, cellular localizations of electron ...	1982	6127735
microcalorimetric studies of the growth of sulfate-reducing bacteria: comparison of the growth parameters of some desulfovibrio species.	we performed a comparative study of the growth energetics of some species of desulfovibrio by measuring microcalorimetric and molar growth yield values. lactate and pyruvate were used as energy sources for sulfate reduction. on lactate-sulfate media desulfovibrio desulfuricans norway, desulfovibrio gigas, and desulfovibrio africanus exhibited molar growth yields of 4.1 +/- 0.6, 3.7 +/- 1.7, and 1.8 +/- 0.1 g/mol, respectively, whereas on pyruvate-sulfate media the molar growth yields were higher ...	1982	7056697
core dimensions in the 3fe cluster of desulfovibrio gigas ferredoxin ii by extended x-ray absorption fine structure spectroscopy.	we have obtained the iron k-edge extended x-ray adsorption fine structure spectra of the 3fe ferredoxin ii of desulfovibrio gigas in the oxidized and reduced states. for both states, interpretation of the exafs data suggests that the fe-s first shell coordination distance is near 2.25 a, in agreement with crystallographic studies of model compounds and proteins containing 2fe-2s and 4fe-4s centers, as well as with a recent crystallographic study of azotobacter vinelandii ferredoxin i (ghosh, d., ...	1982	7085594
complete amino acid sequence of the 4fe-4s, thermostable ferredoxin from clostridium thermoaceticum.	the complete amino acid sequence of the 4fe-4s ferredoxin from the thermophilic bacterium clostridium thermoaceticum has been determined. the protein is extremely thermostable and is the only known clostridial ferredoxin to contain a single [4fe-4s] cluster. the sequence totals 63 residues and includes the first tryptophan (trp-26) reported for a clostridial ferredoxin, and other amino acids not commonly found in clostridial or clostridial-like ferredoxins: methionine (met-1), histidine (his-33) ...	1982	7115670
non-heme iron proteins of desulfovibrio: the primary structure of ferredoxin i from desulfovibrio africanus.	three different ferredoxins have been isolated from the sulfate reducing bacterium, desulfovibrio africanus. the present paper describes the complete amino acid sequence of d. africanus ferredoxin i. this sequence was determined using automatic protein sequencing in liquid phase and in solid phase. the 61 amino acid residues of the sequence have been aligned with the aid of peptides obtained by cyanogen bromide, cleavage and by tryptic hydrolysis. this ferredoxin which contains 4 cysteine residu ...	1982	7126685
a novel iron protein from desulfovibrio gigas.	the isolation, purification, and partial characterization of a novel iron-containing protein from the sulfate-reducing anaerobic bacterium, desulfovibrio gigas, is described. the highly insoluble protein was isolated from the cell debris following osmotic shock of the bacteria. the insoluble fraction consistently contained about 90% of the cell-associated iron. elemental analysis of a crude protein preparation gave 5.3% iron, 2.9% sulfur and 11.9% nitrogen. an independent colorimetric iron analy ...	1982	7150664
reconstitution of liver nadh: cytochrome b5 oxidoreductase and of desulfovibvio vulgaris flavodoxin with 1-carba-1-deazaflavin.	flavin-free cytochrome b5 reductase was reconstituted with 1-deazaflavin and 5-deazaflavin mononucleotides and dinucleotides. the 5-deazaenzyme functioned in transhydrogenation reactions but lacked electron transferase activity. the 1-deazaenzyme was fully competent for both input and output reactions. the flavin reduction rate was lowered about sevenfold upon n-1 substitution of fad, but hydrogen abstraction from nadh remained the limiting step. autoxidation of the reduced enzyme was more rapid ...	1982	7151784
microbial transformations of inorganic sulphur compounds in soil under conditions of heterocontinuous cultivation.	development and activity of the association of the sulphur cycle bacteria, represented by thiobacillus thioparus and desulfovibrio sp., were followed in chernozem soil continuously supplemented with sodium thiosulphate. the technique of heterocontinuous cultivation made it possible (i) to determine changes in the individual components of microflora involved in successive metabolic steps, their time and space sequence, (ii) to follow changes in the transformations of substrate and formation of me ...	1982	7173746
cytochrome c3 from the sulfate-reducing anaerobe desulfovibrio africanus benghazi: antigenic properties.	antisera were prepared against cytochromes c3 from desulfovibrio africanus, d. vulgaris, and d. salexigens. cross-reactions were observed between antisera to d. vulgaris and d. africanus cytochromes and heterologous cytochromes c3. a weak cross-reaction with antisera against both d. vulgaris and d. africanus cytochromes and the acid form of the d. salexigens cytochrome was seen; the basic form did not react.	1982	6181052
assimilatory sulfur metabolism in marine microorganisms: considerations for the application of sulfate incorporation into protein as a measurement of natural population protein synthesis.	the sulfur content of residue protein was determined for pure cultures of nitrosococcus oceanus, desulfovibrio salexigens, 4 mixed populations of fermentative bacteria, 22 samples from mixed natural population enrichments, and 11 nutritionally and morphologically distinct isolates from enrichments of sargasso sea water. the average 1.09 +/- 0.14% (by weight) s in protein for 13 pure cultures agrees with the 1.1% calculated from average protein composition. an operational value encompassing all m ...	1982	16345919
influence of acetylene on growth of sulfate-respiring bacteria.	at a concentration of 20% of the atmosphere of the culture flasks, acetylene inhibited growth and carbon dioxide production by desulfovibrio desulfuricans and desulfovibrio gigas. the bacteria did not reduce acetylene to ethylene, and neither acetylene dicarboxylic acid nor ethylene was inhibitory. at 10%, acetylene was partially inhibitory for the desulfovibrios. at 5%, acetylene impeded the rate but did not limit the extent of growth and catabolism of the desulfovibrios. desulfotomaculum rumin ...	1982	16345981
photosensitized production of hydrogen by hydrogenase in reversed micelles.	hydrogenase (hydrogen:ferricytochrome c(3) oxidoreductase, ec 1.12.2.1) from desulfovibrio vulgaris was encapsulated in reversed micelles with cetyltrimethylammonium bromide as surfactant and a chloroform/octane mixture as solvent. reducing equivalents for hydrogenase-catalyzed hydrogen production were provided by vectorial photosensitized electron transfer from a donor (thiophenol) in the organic phase through a surfactant-ru(2+) sensitizer located in the interphase to methyl viologen concentra ...	1982	16593204
ascorbate as a substrate for photoproduction of hydrogen by photosystem i of chloroplasts.	the photoproduction of hydrogen by 2-(3,4-dichlorophenyl)-1,1-dimethylurea (dcmu)-inhibited chloroplasts from ascorbate under anaerobic conditions was studied in the ph range 5.0 to 7.5 using methyl viologen (mv), n,n,n',n'-tetramethyl-p-phenylenediamine (tmpd), and excess hydrogenase from desulfovibrio desulfuricans. (a) at neutral and basic phs, the photoreduction of mv, which reacted back with photoxidized ascorbate (dehydroascorbate [dhasc]), and the rates of h(2) photoproduction were very l ...	1982	16662354
[carbon monoxide utilization by anaerobic bacteria].		1982	6815248
inorganic pyrophosphate: energy source for sulfate-reducing bacteria of the genus desulfotomaculum.	sulfate-reducing bacteria belonging to the genus desulfotomaculum utilized inorganic pyrophosphate as a source of energy for growth in the presence of fixed carbon (acetate and yeast extract) and sulfate. pyrophosphate does not support the growth of desulfovibrio under the same growth conditions. over a limited range of concentrations, growth is proportional to pyrophosphate, and extracts of bacteria grown on pyrophosphate medium have enzymatic activities similar to extracts prepared from bacter ...	1982	17791517
anaerobic degradation of lactate by syntrophic associations of methanosarcina barkeri and desulfovibrio species and effect of h(2) on acetate degradation.	when grown in the absence of added sulfate, cocultures of desulfovibrio desulfuricans or desulfovibrio vulgaris with methanobrevibacter smithii (methanobacterium ruminantium), which uses h(2) and co(2) for methanogenesis, degraded lactate, with the production of acetate and ch(4). when d. desulfuricans or d. vulgaris was grown in the absence of added sulfate in coculture with methanosarcina barkeri (type strain), which uses both h(2)-co(2) and acetate for methanogenesis, lactate was stoichiometr ...	1981	16345708
syntrophomonas wolfei gen. nov. sp. nov., an anaerobic, syntrophic, fatty acid-oxidizing bacterium.	an anaerobic, nonphototrophic bacterium that beta-oxidizes saturated fatty acids (butyrate through octanoate) to acetate or acetate and propionate using protons as the electron acceptor (h(2) as electron sink product) was isolated in coculture with either a non-fatty acid-degrading, h(2)-utilizing desulfovibrio sp. or methanogens. three strains of the bacterium were characterized and are described as a new genus and species, syntrophomonas wolfei. s. wolfei is a gram-negative, slightly helical r ...	1981	16345745
conversion of cellulose to methane and carbon dioxide by triculture of acetivibrio cellulolyticus, desulfovibrio sp., and methanosarcina barkeri.	the fermentation of cellulose by monocultures of acetivibrio cellulolyticus and cocultures of a. cellulolyticus-methanosarcina barkeri, a. cellulolyticus-desulfovibrio sp., and a. cellulolyticus-m. barkeri-desulfovibrio sp. was studied. the monoculture produced ethanol, acetate, h(2), and co(2). more acetate and less ethanol was formed by the cocultures than by the monoculture. acetate was utilized by m. barkeri in coculture with a. cellulolyticus after a lag period, whereas ethanol was metaboli ...	1981	16345841
comparative bioenergetics of sulfate reduction in desulfovibrio and desulfotomaculum spp.	extracts of desulfotomaculum nigrificans, desulfotomaculum orientis, and desulfotomaculum ruminis exhibit low levels of inorganic pyrophosphatase but were found to have high levels of pyrophosphate:acetate phosphotransferase. conversely, extracts of desulfovibrio gigas, desulfovibrio vulgaris, and desulfovibrio desulfuricans norway 4 were shown to have high levels of inorganic pyrophosphatase but negligible amounts of pyrophosphate:acetate phosphotransferase. both enzymes are reductant activated ...	1981	6109714
studies on sulfite reduction by desulfovibrio vulgaris.	dissimilatory reduction of sulfites by desulfovibrio vulgaris was investigated. medium with alpha-glycerophosphate as a source of organic carbon and phosphorus was applied. it was found that sulfite at the concentration up to 1m na2so3 is not toxic for d. vulgaris and acts efficiently as an electron acceptor. basing on the presented results, a general mechanism of microbiological transformation of sulfites is proposed.	1981	6174026
syntrophic association of a butyrate-degrading bacterium and methanosarcina enriched from bovine rumen fluid.	an anaerobic butyrate-degrading bacterium, morphologically similar to syntrophomonas wolfei, was isolated in coculture with desulfovibrio strain g11 from an enrichment of bovine rumen fluid. a methanosarcina species was the major h2-using organism in the enrichment. the results are discussed in relationship to the absence of methanospirillum hungatei, the h2-using methanogen usually found in association with s. wolfei, and the finding of methanosarcina rather than methanobrevibacter ruminantium ...	1981	7224635
localization of dehydrogenases, reductases, and electron transfer components in the sulfate-reducing bacterium desulfovibrio gigas.	various dehydrogenases, reductases, and electron transfer proteins involved in respiratory sulfate reduction by desulfovibrio gigas have been localized with respect to the periplasmic space, membrane, and cytoplasm. this species was grown on a lactate-sulfate medium, and the distribution of enzyme activities and concentrations of electron transfer components were determined in intact cells, cell fractions prepared with a french press, and lysozyme spheroplasts. a significant fraction of formate ...	1981	7240092
kinetics of methyl viologen reduction by hydrogen catalyzed by hydrogenase from desulfovibrio vulgaris.		1981	7252493
phospholipid biosynthesis in some anaerobic bacteria.	we have identified and characterized enzymes of phospholipid synthesis in two plasmalogen-rich anaerobes. megasphaera elsdenii and veillonella parvula, and one anaerobe lacking plasmalogens. desulfovibrio vulgaris. all three species contained phosphatidate cytidylyltransferase and phosphatidylserine synthase. phosphatidylglycerophosphate synthesis was detected only d. vulgaris extracts. phosphatidylserine (diacyl form) was the major product of the phosphatidylserine synthase assay with particles ...	1981	6263870
the three-iron cluster in a ferredoxin from desulphovibrio gigas. a low-temperature magnetic circular dichroism study.	ferredoxin ii from desulphovibrio gigas is a tetrameric protein containing a novel iron-sulphur cluster consisting of three iron atoms. the low-temperature magnetic circular dichroism (mcd) spectra of the oxidized and dithionite-reduced forms of ferredoxin ii have been measured over the wavelength range approx. 300-800 nm. both oxidation levels of the cluster are shown to be paramagnetic, although only the oxidized form gives an epr signal. mcd magnetization curves have been constructed over the ...	1981	6268181
the structure of cytochrome c3 from desulfovibrio vulgaris miyazaki at 2.5 a resolution.	the structure of tetraheme cytochrome c3 isolated from desulfovibrio vulgaris miyazaki has been determined at 2.5 a resolution by an x-ray diffraction method. protein phases were computed by the multiple isomorphous replacement method using the native and four heavy atom derivatives, anomalous scattering measurements of the latter being considered. the mean figure of merit was 0.77. four heme groups are exposed on the surface of the molecule. there are some short helical segments in the polypept ...	1981	6268619
on cytochrome c3 folding.	the structure of cytochrome c3 from desulfovibrio vulgaris miyazaki (dvm) is considered in detail by scrutinizing main chain folding together with the structure of the protein from d. desulfuricans norway (ddn). the relative arrangement of the four heme groups in this molecule is similar to that of ddn and the disposition of alpha-carbon atoms of cysteine and histidine residues binding to heme groups is also similar. structural differences between the two proteins occur in the shape of some spec ...	1981	6277878
corrosion of mild and stainless steel by four tropical desulfovibrio desulfuricans strains.	the corrosion potential of four tropical desulfovibrio desulfuricans isolates was determined using a semicontinuous batch culture technique in a 56-day test incubated at 37 degrees c. the corrosion potentials for mild and stainless steel of marine or brackish water isolates (0.55 and 0.0026 mg cm-2 day-1) were observed to be approximately twice those of freshwater isolates (0.23 and 0.0014 mg cm-2 day-1). under comparable experimental conditions of severe anaerobic corrosion, stainless steel was ...	1981	7011522
proton translocation associated with nitrite respiration in desulfovibrio desulfuricans.	proton translocation by desulfovibrio desulfuricans cells, cultured anaerobically with nitrate as terminal oxidant, was studied by the oxidant-pulse method. nitrate-grown d. desulfuricans translocated protons rapidly and reproducibly with hydrogen as reductant and nitrite as electron acceptor. h+/2e- ratios were typically in the range 1.8-2.2. proton translocation following pulses of nitrite was also observed with endogenous substrate in freshly harvested cells and with lactate or formate as ele ...	1981	7016854
a cobalt porphyrin containing protein reducible by hydrogenase isolated from desulfovibrio desulfuricans (norway).		1981	7036994
microcalorimetric studies of the growth of sulfate-reducing bacteria: energetics of desulfovibrio vulgaris growth.	the metabolism of desulfovibrio vulgaris hildenborough grown on medium containing lactate or pyruvate plus a high concentration of sulfate (36 mm) was studied. molecular growth yields were 6.7 +/- 1.3 and 10.1 +/- 1.7 g/mol for lactate and pyruvate, respectively. under conditions in which the energy source was the sole growth-limiting factor, we observed the formation of 0.5 mol of hydrogen per mol of lactate and 0.1 mol of hydrogen per mol of pyruvate. the determination of metabolic end product ...	1981	7462143
characterization of a new type of ferredoxin from desulfovibrio africanus.	a new ferredoxin designated ferredoxin iii has been isolated from desulfovibrio africanus grown on media high in iron. native ferredoxin iii is a dimer constituted by two identical subunits of approx. 7500. it is distinguished from the two other ferredoxins (i and ii) isolated from this microorganism by its amino acids composition, n-terminal sequence, spectral properties and iron-sulfur content. the amino acid composition of d. africanus ferredoxin iii is typical of ferredoxins with an excess o ...	1981	7470499
[utilization of some analogues of glycerophosphate by the sulphate-reducing bacteria "desulfovibrio vulgaris" (author's transl)].	utilization of dihydroxyacetate phosphate, glyceraldehyde phosphate, 2-phosphoglyceric and 3-phosphoglyceric acids by the sulphate-reducing bacteria desulfovibrio vulgaris has been studied. on the grounds of stoichiometric relations of reactants and thermodynamic considerations, suitable mechanisms have been proposed for the above reactions.	1981	7258898
[geomicrobiological studies. xiv. heavy metal tolerance of desulfurizing bacteria under various ecological conditions].	tolerance and adaptation to heavy metals of desulfovibrio- and desulfotomaculum-strains of different origin have been investigated in enrichment cultures under different conditions of sulphate supply. three groups of low, medium, and high toxicity were found with as, v, and mo in the first, ni, sb, co, and hg in the second, and cd, zn, u, and cu in the third group. if the so"4-supply was restricted to heavy metal sulphates with a relation of 1:1 of heavy metal- and so"4 -ions (2:3 with sb2(so4)3 ...	1981	7269648
d-lactate dehydrogenase of desulfovibrio vulgaris.	d-lactate dehydrogenase, the starting enzyme for carbon and energy metabolism in dissimilatory sulfate-reducing bacteria, has been purified 36-fold from the soluble fraction of the sonicate of desulfovibrio vulgaris, miyazaki. the enzyme is specific for d-lactate (km = 0.8 mm) and dl-2-hydroxybutyrate (probably its d-isomer) as the electron donor substrate. it reduces, in the presence of lactate, various artificial electron acceptors such as 1-methoxyphenazinium methyl sulfate, ferricyanide, tet ...	1981	7275946
resonance raman spectra of three-iron centers in ferredoxins from desulfovibrio gigas.	the resonance raman spectra of ferredoxins (fd) i and ii from desulfovibrio gigas are reported using 4579 a ar+ laser excitation. the (3fe-3s) center in fd ii has a characteristic resonance raman spectrum, readily distinguishable from those of (2fe-2s) or (4fe-4s) clusters. reduction of fd ii produces a marked alteration in the resonance raman spectrum. fd i is shown to contain both (3fe-3s) and (4fe-4s) fd-type clusters. the results illustrate the potential of resonance raman spectroscopy in fe ...	1981	7275978
proton magnetic resonance studies of azotobacter vinelandii ferredoxin i. evidence for a difference in coordination of the 3fe centers in azotobacter vinelandii ferredoxin i and desulfovibrio gigas ferredoxin ii.	proton magnetic resonance studies have been made of azotobacter vinelandii ferredoxin i. this protein contains a low potential 3fe-3s center (emp = -424 mv) and a high potential 4fe-4s center (emp = +320 mv). a series of five single proton resonances are visible downfield of 11 ppm in the isolated form of the protein. on reduction of the protein the three most downfield resonances are no longer visible and no new resonances are observed. these resonances are assigned to alpha-ch cysteinyl proton ...	1981	7298654