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the primary acceptor of bacterial photosynthesis: its operating midpoint potential? 19764013
camp phosphodiesterase from phototrophic bacteria rhodospirillum rubrum.camp phosphodiesterase activity is discovered in supernatant of r. rubrum cell homogenate after centrifugation at 1000 g. the enzyme is highly active (5.62 nmoles/mg of protein per 1 min) at a broad ph range--from 7.0 to 9.0. the enzyme activity is strongly inhibited with caffeine and dithiotreitol and very significantly inhibited by ascorbic acid. the dependence of the enzyme activity on the incubation time and protein and substrate concentrations in the reaction mixture is estimated. camp phos ...197614724
adenosine-5'-phosphosulfate (aps) as sulfate donor for assimilatory sulfate reduction in rhodospirillum rubrum.crude extracts of rhodospirillum rubrum catalyzed the formation of acid-volatile radioactivity from (35s) sulfate, (35s) adenosine-5'-phosphosulfate, and (35s) 3'-phosphoadenosine-5'-phosphosulfate. an enzyme fraction similar to aps-sulfotransferases from plant sources was purified 228-fold from rhodospirillum rubrum. it is suggested here that this enzyme is specific for adenosine-5'-phosphosulfate, because the purified enzyme fraction metabolized adenosine-5'-phosphosulfate; 3'-phosphoadenosine ...197716577
fermentative metabolism of pyruvate by rhodospirillum rubrum after anaerobic growth in darkness.rhodospirillum rubrum grew anaerobically in darkness and fermented sodium pyruvate by a pyruvate formate-lyase reaction. during 30 min of anaerobic dark or light incubation with sodium pyrivate, crude extracts from fermentatively grown cells produced about 6 micronmol of acetylphosphate and formate per mg of protein in reactions performed at ph 8.3. cell extracts also catalyzed the exchange of sodium 14cformate into sodium pyruvate at an apparent ph optimum of 7.3 to 7.5, but only about 2.5 micr ...197718439
light-induced ph changes and changes in absorbance of ph indicators in rhodospirillum rubrum chromatophores.1. the light-induced ph change of chromatophore suspensions from rhodospirillum rubrum was stimulated significantly and similarly by kcl, nacl, licl, rbcl, cscl, mgcl2, mncl2, and cacl2. in the dark, the ph of chromatophore suspensions decreased immediately and markedly on adding these salts. 2. the light-induced ph change stimulated by kcl plus valinomycin was inhibited by licl and nacl, but not by rbcl. 3. the optimum ph values for light-induced ph change and photosynthetic atp formation were ...197722540
resolution and reconstitution of rhodospirillum rubrum pyridine dinucleotide transhydrogenase. ii. solubilization of the membrane-bound component.the rhodospirillum rubrum pyridine dinucleotide transhydrogenase system is comprised of a membrane-bound component and an easily dissociable soluble factor. active transhydrogenase complex was solubilized by extraction of chromatophores with lysolecithin. the membrane component was also extracted from membranes depleted of soluble factor. the solubilized membrane component reconstituted transhydrogenase activity upon addition of soluble factor. various other ionic and non-ionic detergents, inclu ...197723085
the proton pump is a molecular engine of motile bacteria. 197824186
pms photo-inhibition in rhodospirillum rubrum membranes in the presence of permeant entities affecting either the deltapsi or the deltaph components of the protonmotive force. 197829789
light-dependent uptake of hydrogen ions in chloroplasts and chromatophores: effects of hearing, solvents and detergents.the effects of heating, organic solvents and detergents on the light-dependent hydrogen ion uptake in chloroplasts and chromatophores and the coupled photophosphorylation were compared. it was shown that the membrane structure of the chromatophores is much more stable than that of the chloroplast thylacoids. the activation of the ph function in the chromatophores in the presence of low concentrations of diethyl ether and detergents was noted. the effects observed may be due to the changes in the ...197722359
comparative study of nadp-reductase properties in two species of purple bacteria.unlike rhodospirillum rubrum, the highly purified preparations of nadp-reductase thiocapsa roseopersicina are capable of reduction of cytochrome c though they do not catalyse diaphorase reaction in the presence of methyl viologen or benzyl viologen and nadh. t. roseopersicina reductase has more high temperature optimum (50-65 degrees) and more high thermal stability (65 degrees) and it is capable to catalyse diaphorase and menadione-reductase reactions under more high ph values (11.0-12.0) than ...197720991
resonance raman study of the ph-dependent and detergent-induced structural alterations in the heme moiety of rhodospirillum rubrum cytochrome c'.the resonance raman spectra and the structures of the heme moiety of rhodospirillum rubrum cytochrome c' were investigated for its five states characterized by absorption spectra; types-a and -n of the reduced form and types-i, -ii, and -iii of the oxidized form. the frequency of the ligand-sensitive raman line suggested the coordination of lysine (nepsilon) at the sixth position of the heme iron of type-n. the sixth ligand of type-iii was deduced to be either lysine or histidine but would not b ...197720977
[activation and inhibition of photoinduced proton absorption in rhodospirillum rubrum chromatophores by detergents and solvents].the effects of detergents (triton x-100) and solvents (diethyl ether, metanol) on the reversible light-induced proton uptake, photophosphorylation and band shift of the carotenoid in chromatophores from r. rubrum are described. all these compounds were found to stimulate the extent of light-induced proton uptake with subsequent inhibition when the concentrations were increased. stimulation of proton uptake is accompanied by inhibition of both phosphorylation and carotenoid absorbance shift.197937926
multiple forms of dna-dependent rna and polyadenylic acid polymerases from heterotrophically grown rhodospirillum rubrum.three, two major and one minor, distinct rna polymerases have been isolated and partially purified from heterotrophically grown rhodospirillum rubrum, a facultative photosynethetic bacterium. associated with each of these three enzymes is a distinct polyadenylic acid polyemrase. all of these enzyme activities are dependent on dna templates and are resistant to rifampicin and streptovaricin. the structural subunit composition, the response to various chemical compounds and dna templates, and the ...197717456
interconversion of two kinetically distinct states of the membrane-bound and solubilised h+-translocating atpase from rhodospirillum rubrum. 197715868
electrochemical gradient of h+ ions as an immediate source of energy during bacteria movement.an uncoupler of oxidative phosphorylation causes an instantaneous cessation of movement of bacteria rhodospirillum rubrum in the presence and in the absence of oligomycin. it is concluded that such cessation is not due to a decrease in the atp concentration but to the elimination of deltamicron-h+ by the uncoupler. the mobility of the bacteria does not practically change in the presence of acetate and is, to some extent, decreased after addition of valinomycin or penetrating cation of tetrapheny ...197615648
photoproduction of ammonium ion from n2 in rhodospirillum rubrum.nh+4 excretion was undetectable in n2-fixing cultures of rhodospirillum rubrum (s-1) and nitrogenase activity in these cultures was repressed by the addition of 10 mm nh+4 to the medium. the glutamate analog, l-methionine-dl-sulfoximine (msx), derepressed n2 fixation even in the presence of 10 mm extracellular nh+4. when 10 mg msx/ml was added to cultures just prior to nitrogenase induction they developed nitrogenase activity (20% of the control activities) and excreted most of their fixed n2 as ...197613753
growth of spirillum lipoferum at constant partial pressures of oxygen, and the properties of its nitrogenase in cell-free extracts.spirillum lipoferum, an n2-fixing organism, was grown at constant concentrations of dissolved o2. when supplied with nh4+ aerobically, its doubling time was 1 h; when it fixed n2 microaerophilically, its doubling time was 5-5 to 7 h and the optimal po2 for growth was 0-005 to 0-007 atm. at its optimal po2 for growth on n2, s. lipoferum assimilated 8 to 10 mg nitrogen/g carbon substrate used; its efficiency was less at higher po2 levels. nitrogenase in cell-free extracts required mg2+ and mn2+, a ...197713147
multiple low spin forms of the cytochrome c ferrihemochrome. epr spectra of various eukaryotic and prokaryotic cytochromes c.1. despite the same methionine-sulfur:heme-iron:imidazole-nitrogen hemochrome structure observed by x-ray crystallography in four of the seven c-type eukaryotic and prokaryotic cytochromes examined, and the occurrence of the characteristic 695 nm absorption band correlated with the presence of a methionine-sulfur:heme-iron axial ligand in all seven proteins, they fall into two distinct classes on the basis of their epr and optical spectra. the horse, tuna, and bakers' yeast iso-1 cytochromes c ...197713072
fermentation of pyruvate by 7 species of phototrophic purple bacteria.the dark, anaerobic fermentation of pyruvate under growth conditions was examined with the following species of phototrophic purple bacteria: rhodospirillum rubrum strains ha and s1, rhodopseudomonas gelatinosa strain 2150, rhodopseudomonas acidophila strain 7050, rhodopseudomonas palustris strain atcc 17001, rhodopseudomonas capsulata strains kb1 and 6950, rhodopseudomonas sphaeroides strain atcc 17023, and chromatium vinosum strain d. fermentation balances were established for all experiments. ...197612621
phosphate binding to chromatophores of rhodospirillum rubrum.equilibrium dialysis has been used to determine the binding of phosphate to chromatophores of rhodospirillum rubrum. assuming a complete exchange of the added 32pi with endogenous phosphate, the saturation with phosphate retained in any form by chromatophores was reached at about 20 nmoles pi per mg of bacteriochlorophyll. the retention of phosphate had a ph optimum at ph 6.5 to 6.8. at ph 8.0 only chromatophores which have not been liberated from dna and rna show a considerable retention of pho ...19769278
effects of ph indicators on various activities of chromatophroes of rhodospirillum rubrum.1. the effects of ph indicators on activities for atp hydrolysis in the dark and atp-pi exchange in the dark were examined with chromatophores from rhodospirillum rubrum. of thirty-one ph indicators tested, eleven (metanil yellow, 2, 4-dinitrophenol, ethyl orange, bromocresol green, resazurin, neutral red, bromthymol blue, alpha-naphtholphthalein, o-cresolphthalein, phenolphthalein, and alizarin yellow g) almost completely inhibited the activities for atp formation and atp-pi exchange at concent ...19755425
d-alpha-hydroxyglutarate dehydrogenase of rhodospirillum rubrum.d-alpha-hydroxyglutarate dehydrogenase of r. rubrum grown anaerobically in the light was partially purified and some properties were investigated. 1. the enzyme catalyze stoichiometrically the dehydrogenation reaction of d-alpha-hydroxyglutarate into alpha-oxoglutarate, coupled with the reduction of 2, 6-dichlorophenolindophenol. 2. cytochrome c2, cytochrome c, and ferricyanide are effective as electron acceptors with the crude enzyme but not with the purified one, whereas nad+ and nadp+ are com ...19755424
pyruvate fermentation in rhodospirillum rubrum and after transfer from aerobic to anaerobic conditions in the dark.the fermentative metabolism of rhodospirillum rubrum (strain ha, f1, s1) was studied after transfering the cells from aerobic to anaerobic dark culture conditions. pyruvate was metabolized mainly to acetate and formate, and to a lesser extent to co2 and priopionate, by all strains. therefore, pyruvate formate lyase would appear to be the characteristic key enzyme of the dark anaerobic fermentation metabolism in r. rubrum. strain f1 and s1 metabolized the formate further to h2 and co2. it is conc ...19763145
polarographic studies on ubiquinone-10 and rhodoquinone bound with chromatophores from rhodospirillum rubrum.redox components bound with chromatophores of rhodospirillum rubrum, and pure samples of ubiquinone-10 and rhodoquinone were studied polarographically at 24 degrees. in a mixture of ethanol and water (4 : 1, v/v) at ph 7, ubiquinone-10 and rhodoquinone had half-wave potentials (e1/2) of +43 mv and -63 mv, respectively. for both quinones, values of the electron transfer number (n) were 2 , and plots of e1/2 versus ph formed straight lines with slopes of -30 mv/ph in the neutral ph range; thus, va ...19752586
oxidation-reduction properties of chromatium vinosum high potential iron-sulfur protein.the oxidation-reduction properties of the high potential iron-sulfur protein (hipip) from chromatium vinosum have been investigated. both equilibrium and kinetic measurements demonstrate electron transport by hipip is ph independent in the ph range 7-11. the kinetics of reduction (potassium ferrocyanide, so2, s2o42-, sodium ascorbate, and rhodospirillum rubrum cytochrome c2) and oxidation (potassium ferricyanide and rhodospirillium rubrum cytochrome c2) of hipip are reported. based on the data o ...19762285
alcohol dehydrogenase activity of nonsulfur purple bacteria.rhodopseudomonas palustris, rh. viridis, rh. acidophila, and rhodomicrobium vanniellii grow on media containing ethanol, n-propanol, and n-butanol. the highest amount of lower alcohols is utilized by the strains of rh. palustris. only rh. acidophila accumulates methanol. alcohol dehydrogenase of rh. palustris, rh. viridis, and rhodospirillum rubrum requires for its activity nad, that of rhodomicrobium vanniellii--nadp, and the enzyme of rh. acidophila is active in the presence of phenazine metas ...19751631
proton nuclear magnetic resonance studies of rhodospirillum rubrum cytochrome.rhodospirillum rubrum cytochrome c2 was studied by proton nuclear magnetic resonance at 220 mhz. assignments were made to the resonances of heme c by double-resonance techniques and by temperature-dependence studies. the aromatic resonances of trp-62 and tyr-70 of ferrocytochrome c2 were identified by spin-decoupling experiments. the resonances of the met-91 methyl group of the ferri- and ferrocytochromes were assigned by saturation-transfer experiments. the assignments are compared to those mad ...197934433
picosecond detection of bchl-800 as an intermediate electron carrier between selectively-excited p870 and bacteriopheophytin in rhodospirillum rubrum relaction centers. 197897097
isolation, characterization, and crystallization of ribulosebisphosphate carboxylase from autotrophically grown rhodospirillum rubrum.serial culture of rhodospirillum rubrum with 2% co2 in h2 as the exclusive carbon source resulted in a rather large fraction of the soluble protein (greater than 40%) being comprised of ribulosebisphosphate carboxylase (about sixfold higher than the highest value previously reported). isolation of the enzyme from these cells revealed that it has physical and kinetic properties similar to those previously described for the enzyme derived from cells grown on butyrate. notably, the small subunit (w ...197933152
dna-dependent rna and polyadenylic acid polymerase from phototrophically grown rhodospirillum rubrum.dna-dependent rna and polyadenylic acid polymerases have been purified from phototrophic rhodospirillum rubrum. their properties have been found to be very similar to those of the previously reported heterotrophic r. rubrum enzymes. however, several important differences do exist between the enzymes from the phototrophic and the heterotrophic cells, such as the lack of response to added polyadenylic acid for poly a synthesis and the presence of the sigma subunit in the phototrophic enzymes. fur ...197831974
reversible conversion from ca(2)+-atpase activity to mg(2)+- and mn(2)+-atpase activities of coupling factor purified from acetone powder of rhodospirillum rubrum chromatophores.it is known that the coupling factor purified from the acetone powder of chromatophores from rhodospirillum rubrum shows atpase activity in the presence of ca(2)+, but not in the presence of mg(2)+ or mn(2)+. the present study deals with conditions, under which the ca(2)+-atpase activity is reversibly converted into mg(2)+- and mn(2)+-atpase activites with the purified coupling factor. 1. of the ph indicators tested, 6 kinds coverted the ca(2)+-atpase activity into mg(2)+- and mn(2)+-atpase acti ...197830771
affinity chromatography of h+-translocating adenosine triphosphatase isolated by chloroform extraction of rhodospirillum rubrum chromatophores. modification of binding affinity by divalent cations and activating anions.1. atpase isolated from rhodospirillum rubrum by chloroform extraction and purified by gel filtration or affinity chromatography shows three bands (alpha, beta and gamma) upon electrophoresis in sodium dodecyl sulphate. 2. ca2+-atpase activity of the preparation is inhibited by aurovertin and efrapeptin but not by oligomycin. activity may be inhibited by treatment with 4-chloro-7-nitrobenzofurazan and subsequently restored by dithiothreitol. 3. the enzyme fails to reconstitute photophosphorylati ...197827212
subcellular distribution and several properties of the camp enzyme system of phototrophic bacteria.in the cells of the phototrophic bacteria rhodospirillum rubrum and rhodopseudomonas palustris the two enzymes of the camp system enzymes - adenylate cyclase and camp phosphodiesterase (pde) exist in a soluble and membrane-bound forms. after mild disruption of the cells (sonication up to 3 min) the activity of both enzymes is found in the chromatophores. in the cells of the two types of bacteria grown under anaerobic conditions soluble adenylate cyclase is predominant. in the cells of r. rubrum ...197826430
modification of rhodospirillum rubrum ribulose bisphosphate carboxylase with pyridoxal phosphate. 1. identification of a lysyl residue at the active site.ribulose 1,5-bisphosphate carboxylase isolated from rhodospirillum rubrum was strongly inhibited by low concentrations of pyridoxal 5'-phosphate. activity was protected by the substrate ribulose bisphosphate and to a lesser extent by other phosphorylated compounds. pyridoxal phosphate inhibition was enhanced in the presence of magnesium and bicarbonate, but not in the presence of either compound alone. concomitant with inhibition of enzyme activity, pyridoxal phosphate forms a schiff base with t ...197826381
role of the large and small subunits of ribulose-1,5-bisphosphate carboxylase in the activation by co2 and mg2+. 197937245
retention of the oxygens at c-2 and c-3 of d-ribulose 1,5-bisphosphate in the reaction catalyzed by ribulose-1,5-bisphosphate carboxylase.ribulose-1,5-bisphosphate carboxylase catalyzes the conversion of d ribulose 1,5-bisphosphate and co2 to 3-phospho-d-glycerate, with retention of the oxygen atoms at both c-2 and c-3 of the substrate. this observation is consistent with mechanistic pathways involving an enediol intermediate and eliminates suggested mechanisms that involve covalent intermediates between the enzyme and ribulose 1,5-bisphosphate in which the substrate oxygen at c-2 or c-3 is compulsorily lost.1978101236
preparation of nitrogenase. 1978101737
the influence of energy-transfer inhibitors on proton permeability and photophosphorylation in normal and preilluminated rhodospirillum rubrum chromatophores.(1) chromatophores were preilluminated in the presence of phenazine methosulphate or diaminodurene, and without phosphorylation substrates; next they were transferred to fresh medium and assayed for light-induced proton uptake, light-induced 9-aminoacridin fluorescence quenching, and photophosphorylation. (2) preillumination in the presence of phenazine methosulphate or diaminodurene causes an inhibition of the photophosphorylation rate. the presence of adp + mgcl2 + phosphate, or adp + mgcl2 + ...197937903
manganese, an essential trace element for n2 fixation by rhodospirillum rubrum and rhodopseudomonas capsulata: role in nitrogenase regulation.nitrogenase (n(2)ase) from the photosynthetic bacterium rhodospirillum rubrum can exist in two forms, an unregulated form (n(2)ase a) and a regulatory form (n(2)ase r), the latter being identified in vitro by its need for activation by a mn(2+)-dependent n(2)ase activating system. the physiological significance of this mn(2+)-dependent n(2)ase activating system was suggested here by observations that growth of r. rubrum and rhodopseudomonas capsulata on n(2) gas (a condition that produces active ...197942641
origin of the atp formed during the light-dependent oxygen uptake catalyzed by rhodospirillum rubrum chromatophores.the oxygen uptake which is observed when rhodospirillum rubrum chromatophores are illuminated under air and in the presence of reduced 2, 6-dichlorophenolindophenol (dcip), 2, 3, 5, 6-tetra-methyl-p-phenylenediamine (diaminodurene, dad) or n, n'-tetramethyl-p-phenylenediamine (tmdp) depends on the electron-donor concentration according to the equation of michaelis-menten. the apparent km for the donor is lowered by the electron-transfer inhibitor 2-heptyl-4-hydroxyquinoline-n-oxide (hqno) which ...197547212
postillumination adenosine triphosphate synthesis in rhodospirillum rubrum chromatophores. ii. stimulation by a k+ diffusion potential.addition of valinomycin, nonactin, or monactin plus kcl in the dark to preilluminated chromatophores induced the synthesis of a large amount of atp. this stimulation of postillumination atp synthesis by a dark-imposed k+ diffusion potential was different from the stimulation caused by addition of permeant anions or cations in the light, since it increases when the ph of the light stage decreased from 8.0 to 6.0. it was thus most pronounced when the chromatophores were preloaded with protons but ...197549352
pyruvate fermentation in light-grown cells of rhodospirillum rubrum during adaptation to anaerobic dark conditions.pyruvate fermentation in rhodospirillum rubrum (strains f1, s1, and ha) was investigated using cells precultured on different substrates anaerobically in the light and than transferred to anaerobic dark conditions. pyruvate formate lyase was always the key enzyme in pyruvate fermentation but its activity was lower than in cells which have been precultured aerobically in darkness. the preculture substrate also had a clear influence on the pyruvate formate lyase activity. strains f1 and s1 metabol ...1978103509
generation of electric current by chromatophores of rhodospirillum rubrum and reconstitution of electrogenic function in subchromatophore pigment-protein complexes.lipoprotein complexes, containing (1) bacteriochlorophyll reaction centers, (2) bacteriochlorophyll light-harvesting antenna or (3) both reaction centers and antenna, have been isolated from chromatophores of non-sulphur purple bacteria rhodospirillum rubrum by detergent treatments. the method of reconstituting the proteoliposomes containing these complexes is described. being associtated with planas azolectin membrane, ptoteoliposomes as well as intact chromatophores were found to generate a li ...197661042
photoinactivation of photophosphorylation and dark atpase in rhodospirillum rubrum chromatophores.preillumination of rhodospirillum rubrum chromatophores with strong, far-red light in the presence of phenazine methosulfate under non-phosphorylation conditions results in a selective, irreversible inactivation (typically about 70%) of photophosphorylation and of uncoupler-stimulated dark atpase. the time course of the photoinactivation is similar to the light-on kinetics of the light-induced proton uptake in the absence of adp. only little photoinactivation occurs when the uncoupler carbonyl c ...197611818
photooxidase system of rhodospirillum rubrum. i. photooxidations catalyzed by chromatophores isolated from a mutant deficient in photooxidase activity.the aerobic photooxidations of reduced 2,6-dichlorophenolindophenol and of reaction-center bacteriochlorophyll (p-870) have been investigated in membrane vesicles (chromatophores) isolated from a non-phototrophic rhodospirillum rubrum strain. in aerobic suspensions of wild-type chromatophores, continuous light elicits an increase of the levels of 2,6-dichlorophenolindophenol and of oxidized p-870, which reach steady-state values shortly after the onset of illumination. in contrast, light induces ...197764259
ribulose 1,5-bisphosphate carboxylase from autotrophic micro-organisms [proceedings]. 1978105954
two forms of nitrogenase from the photosynthetic bacterium rhodospirillum rubrum.acetylene reduction by nitrogenase from rhodospirillum rubrum, unlike that by other nitrogenases, was recently found by other investigators to require an activation of the iron protein of nitrogenase by an activating system comprising a chromatophore membrane component, adenosine 5'-triphosphate (atp), and divalent metal ions. in an extension of this work, we observed that the same activating system was also required for nitrogenase-linked h(2) evolution. however, we found that, depending on the ...1979106042
lipophilic o-antigens in rhodospirillum tenue.lipopolysaccharides of eight wild-type strains of the phototrophic bacterium rhodospirillum tenue have been analyzed. all of the lipopolysaccharides are highly lipophilic. the compositions of preparations obtained by the phenol-water or by the phenol-chloroform-petroleum ether procedure are very similar. the polysaccharide moiety, obtained by mild acid hydrolysis of lipopolysaccharide, consists mainly of aldoheptoses: l-glycero-d-mannoheptose is present in all strains, whereas d-glycero-d-mannoh ...197795659
viability and endogenous substrates used during starvation survival of rhodospirillum rubrum.cells of rhodospirillum rubrum were grown photoorganotrophically and chemoorganotrophically and then starved for organic carbon and combined nitrogen under four conditions: anaerobically in the light and dark and aerobically in the light and dark. illumination prolonged viability and suppressed the net degradation of cell material of phototrophically grown cells, but had no effect on chemotrophically grown cells that did not contain bacteriochlorophyll. the half-life survival times of carbohydra ...197896087
studies on regulatory functions of malic enzymes. v. comparative studies of malic enzymes in bacteria.screening of four malic enzymes--nad-linked enzyme [ec 1.1.1.38], nad, nadp-linked enzyme [ec 1.1.1.39], nadp-linked enzyme [ec 1.1.1.40], and d-malic enzyme--was carried out with cell-free extracts of the following 16 strains of bacteria by the aid of sepharose 6b column chromatography: 9 strains of enteric bacteria, 3 strains of pseudomonas, alcaligenes faecalis, agrobacterium tumefaciens, rhodospirillum rubrum, and clostridium tetanomorphum. all the strains tested contained at least one malic ...197896110
bacteriochlorophyll fluorescence of purple bacteria at low redox potentials. the relationship between reaction center triplet yield and the emission yield.this work describes fluorescence yield measurements in suspensions of strains of rhodospirillum rubrum and rhodopseudomonas sphaeroides in which the iron . quinone complex (x) was chemically reduced (state [pix-]; p is the reaction center bacteriochlorophyll dimer, i is the long wavelength bacteriopheophytin), and compares these with the fluorescence observed when all the traps are open (state [pix]) and with the fluorescence observed when all the traps are closed (state [p+ix]). at 77 k the amp ...197896854
activation of ala synthetase by reduced thioredoxin in rhodopseudomonas spheroides y. 1979109312
flash-induced changes in the in vivo bacteriochlorophyll fluorescence yield at low temperatures and low redox potentials in carotenoid-containing strains of photosynthetic bacteria.the changes in the in vivo bacteriochlorophyll fluorescence induced by a xenon flash at low temperatures (77--200 k) with the "primary" acceptor x chemically prereduced have been examined in whole cells of several species of photosynthetic bacteria which contain carotenoids absorbing in the visible part of the absorption spectrum. two groups of species with different behaviour could be distinguished. in both cases a flash-induced rise of the fluorescence yield was observed with x prereduced at 7 ...197896856
[possible role of macromolecular components in the functioning of photosynthetic reaction centers of purple bacteria].the temperature dependencies of the photoconversion of pigments p870--p890 were studied using isolated chromatophores and photosynthetic reaction centres (rc's) of purple bacteria. the samples were prepared by extraction with organic solvents (light petroleum and a combination of light petroleum and methanol) and modified through cross-linking the functional groups of proteins by treatment with glutaraldehyde or denatured by various physical and chemical treatments. the data provide further evid ...1977109747
isolation of a membrane protein from r rubrum chromatophores and its abnormal behavior in sds-polyacrylamide gel electrophoresis due to a high binding capacity for sds.a membrane protein insoluble in water was isolated by gel chromatography in the presence of 0.1% sodium dodecyl sulfate (sds) from chromatophores of a photosynthetic bacterium, rhodospirillum rubrum. this is one of the major membrane proteins of the chromatophore. the protein was found to bind about four grams of sds per gram, a value which is more than twice the amount generally observed with protein polypeptides derived from water-soluble globular proteins. the electrophoretic behavior of the ...197897280
dichroism of bacteriochlorophyll in chromatophores of photosynthetic bacteria.the dichroism was measured in films of air-dried and, consequently, flattened chromatophores of chromatium vinosum, rhodopseudomonas sphaeroides and rhodospirillum rubrum. the values (deltaa/a) of dichroism in c. vinosum were found to be -1.05 at 590 nm and 0.75 in the near infrared region. the values of dichroism in r. sphaeroides were -0.70 at 590 nm and 0.80 at 870 nm. the values of dichroism in r. rubrum were -1.45 at 590 nm and 0.97 at 870 nm.197897281
nitrogen electron nuclear double resonance and proton triple resonance experiments on the bacteriochlorophyll cation in solution.electron nuclear double resonance signals of the pyrrole nitrogens of bacteriochlorophyll alpha cation in a solution of ch2cl2/ch3oh (6:1) have been observed. the nitrogens are inequivalent: the hyperfine coupling constants were determined to be 2.36 and 3.18 mhz (0.84 and 1.14 g, respectively). triple electron nuclear double resonance experiments have yielded the signs and values of nine proton hyperfine coupling constants. the assignment based on these data agrees well with previous work (borg ...197897667
on the state of carotenoids bound to reaction centers of photosynthetic bacteria: a resonance raman study.the carotenoids bound to reaction centers of wild, ga and gic strains of rhodopseudomonas spheroides, of rhodospirrillum rubrum, strain s1 and of rhodopseudomonas viridis, yield very similar, but unusual resonance raman spectra. through a comparison with resonance raman spectra of 15,15'-cis-beta-carotene, these carotenoids are shown to assume cis conformations, while the corresponding chromatophores contain all-trans forms only. these cis conformations likely are identical for all the carotenoi ...197899169
the mechanism of reduction of the ubiquinone pool in photosynthetic bacteria at different redox potentials.(1) a flash number dependency of flash-induced absorbance changes was observed with whole cells of rhodospirillum rubrum and chromatophores of r. rubrum and rhodopseudomonas sphaeroides wild type and the g1c mutant. the oscillatory behavior was dependent on the redox potential; it was observed under oxidizing conditions only. absorbance difference spectra measured after each flash in the 275--500 nm wavelength region showed that a molecule of ubiquinone, r, is reduced to the semiquinone (r-) aft ...197899172
a kinetic study of ribulose bisphosphate carboxylase from the photosynthetic bacterium rhodospirillum rubrum.the activation kinetics of purified rhodospirillum rubrum ribulose bisphosphate carboxylase were analysed. the equilibrium constant for activation by co(2) was 600 micron and that for activation by mg2+ was 90 micron, and the second-order activation constant for the reaction of co(2) with inactive enzyme (k+1) was 0.25 x 10(-3)min-1 . micron-1. the latter value was considerably lower than the k+1 for higher-plant enzyme (7 x 10(-3)-10 x 10(-3)min-1 . micron-1). 6-phosphogluconate had little effe ...1978100101
purification and properties of nitrogenase from the cyanobacterium, anabaena cylindrica.the nitrogenase complex was isolated from nitrogen-starved cultures of anabaema cylindrica. sodium dithionite, photochemically reduced ferredoxin, and nadph were found to be effective election donors to nitro genase in crude extracts whereas hydrogen and pyruvate were not. the km for acetylene in vivo is ten-fold higher than the km in vitro, whereas this pattern does not hold for the non-heterocystous cyanobacterium, plectonema boryanum. this indicates that at least one mechanism of oxygen prote ...1979111934
[effect of nitrogen-containing compounds on hydrogen light emission and nitrogen fixation by purple bacteria].the cells of rhodospirillum rubrum and thiocapsa roseopersicina grown in media containing glutamate and arginine, respectively, as well as under conditions of nitrogen fixation evolve h2 in the light. if the cultures were grown in media with nh4+, no3-, urea, glutamine or asparagine, hydrogen photoevolution by the cells and acetylene reduction started after the lag-phase and proceeded at a low rate. extracts of such cells did not display the activity of nitrogenase which could be assayed by the ...1979112358
[picosecond energy transfer between the spectral forms of pigments from the reaction center of rhodospirillum rubrum].absorption changes of reaction centers from rhodospirillum rubrum at 748, 796 and 870 nm induced by 532 and 870 nm picosecond light pulses were investigated with a picosecond spectrometer. kinetics of absorption changes at 748 and 796 had an additional bleaching when induced by the 532 nm pulse, in comparison with those at 870 nm. the additional bleaching was interpreted as a result of the excitation energy transfer via spectral forms of pigments of reaction centers. the experimental results fit ...1978100143
involvement of an essential arginyl residue in the coupling activity of rhodospirillum rubrum chromatophores. 1978102254
resolution and reconstitution of rhodospirillum rubrum pyridine dinucleotide transhydrogenase: localization of substrate binding sites. 1978102261
the kinetics of photooxidation of c-type cytochromes by rhodospirillum rubrum reaction centers. 197941489
blue and red shifts of bacteriochlorophyll absorption band around 880 nm in rhodospirillum rubrum.the redox potential dependence of the light-induced absorption changes of bacteriochlorophyll in chromatophores and subchromatophore pigment-protein complexes from rhodospirillum rubrum has been examined. the highest values of the absorption changes due to the bleaching of p-870 and the blue shift of p-800 in chromatophores and subchromatophore complexes are observed in the 360-410mv redox potential range. at potentials below 300 mv (ph 7.0), the 880 nm band of bacteriochlorophyll shifts to shor ...197941575
[shifts of the bacteriochlorophyll absorption band at 880 nm in chromatophores and subchromatophore pigment-protein complexes from rhodospirillum rubrum].the redox potential dependency of the light-induced absorption changes of bacteriochlorophyll in the chromatophores and subchromatophore particles from rhodospirillum rubrum has been studied. the highest values of the absorption changes due to the bleaching of p870 and the blue shift of p800 are observed within the redox potential range of 360--410. at the potential values below 300 mv the 880 nm band of bacteriochlorophyll shifts to shorter wavelengths in the subchromatophore particles and to l ...197941599
energy-liked reactions in photosynthetic bacteria. x. solubilization of the membrane-bound energy-linked inorganic pyrophosphatase of rhodospirillum rubrum. 1978102323
properties of the nitrogenase system from a photosynthetic bacterium, rhodospirillum rubrum.soluble nitrogenase from rhodospirillum rubrum has been isolated and separated into its two components, the mofe protein and the fe protein. the mofe protein has been purified to near homogeneity and has a molecular weight or 215 000. it contains two mo, 25--30 fe and 19--22 acid-labile sulphide and consists of four subunits, mw 56 000. the fe protein has a molecular weight 65 000. it contains approximately four fe and four acid-labile sulphide and consists of two subunits, mw 31 500. the highes ...1978102339
lipopolysaccharides of photosynthetic prokaryotes. 1979115382
oxonol dyes as monitors of membrane potential. their behavior in photosynthetic bacteria.the reponses of oxonol dyes to single and multiple single turnovers of the photosynthetic apparatus of photosynthetic bacteria have been studied, and compared with the responses of the endogenous carotenoid pigments. the absorbance changes of the oxonols can be conveniently measured at 587 nm, because this is an isosbestic point in the 'light-minus-dark' difference spectrum of the chromatophores. the oxonols appear to respond to the light-induced 'energization' by shifting their absorption maxim ...1979103582
purification and properties of nitrogenase from rhodospirillum rubrum, and evidence for phosphate, ribose and an adenine-like unit covalently bound to the iron protein.1. the molybdenum-iron (mo-fe) protein, iron (fe) protein and the activating factor of nitrogenase from rhodospirillum rubrum were purified. 2. the mo-fe protein has properties similar to those of the mo-fe proteins of other nitrogen-fixing organisms. 3. the fe protein is similar to other fe proteins with respect to its molecular weight, metal composition and e.p.r. signal. 4. the fe protein is different from other fe proteins in that it apparently has two types of subunits rather than one, its ...1978104713
complete stabilization of water-soluble hydrogenase from rhodospirillum rubrum under air atmosphere with a high concentration of chloride ions.hydrogenase was easily solubilized from light-grown cells of r. rubrum with 10 mm na ethylenediaminetetraacetate. the enzyme thus obtained was so stable that loss of its activity was undetectable during storage at room temperature for 6 months under air atmosphere, provided that nacl, kcl or cscl was present at greater than or equal to 0.7 m.1978104983
nitrogen fixation and hydrogen metabolism in photosynthetic bacteria.the photosynthetic bacteria are found in a wide range of specialized aquatic environments. these bacteria represent important members of the microbial community since they are capable of carrying out two of the most important processes on earth, namely, photosynthesis and nitrogen fixation, at the expense of solar energy. since the discovery that these bacteria could fix atmospheric nitrogen, there has been an intensification of studies relating to both the biochemistry and physiology of this pr ...197896875
short-lived delayed luminescence of photosynthetic organisms. i. nanosecond afterglows in purple bacteria at low redox potentials.a combined study of emissions of purple bacteria rhodospirillum rubrum, ectothiorhodospira shaposhnikovii and thiocapsa roseopersicina was performed under conditions of low potential. it has been shown that a considerable part of the emission represents a delayed luminescence with a lifetime of about 5 ns and an activation energy delta e = 0.05 +/- 0.03 ev. intensity of this delayed luminescence is approximately equal to that of prompt fluorescence. it diminishes as temperature decreases and als ...1979116682
hydrophobic membrane protein from chromatophores of rhodospirillum rubrum. structural and spectroscopic studies of monolayers and multilayers.a hydrophobic, lipid- and pigment-free polypeptide from the chromatophore membrane of rhodospirillum rubrum was spread from chloroform/methanol, pyridine and formic acid solutions at an air-water interface. surface pressure versus area isotherms of the monolayers formed at the interface were partially dependent upon the spreading solvent used. from the surface area at 20 dynes/cm compression, an average molecular area of 12.9 nm2/molecule was calculated for a polypeptide monolayer spread from ch ...1979110346
[noncyclic electron transport and membrane potential generation in the chromatophores of rhodospirillum rubrum]. 1979110361
in vitro restoration of nitrate reductase: investigation of aspergillus nidulans and neurospora crassa nitrate reductase mutants.extracts of aspergillus nidulans wild type (bi-1) and the nitrate reductase mutant niad-17 were active in the in vitro restoration of nadph-dependent nitrate reductase when mixed with extracts of neurospora crassa, nit-1. among the a. nidulans cnx nitrate reductase mutants tested, only the molybdenum repair mutant, cnxe-14 grown in the presence of 10-minus 3 m na2 moo4 was active in the restoration assay. aspergillus extracts contained an inhibitor(s) which was measured by the decrease in nadph- ...1975123779
the preparation and characterization of different types of light-harvesting pigment-protein complexes from some purple bacteria.a general strategy, with some specific examples, is given for the isolation and purification of detergent-soluble, antenna pigment-protein complexes from the photosynthetic membranes. absorption, fluorescence and circular dichroism spectra, and the pigment and protein composition of b800-b850-protein and b890-protein complexes of some purple bacteria (rhodospirillum rubrum, rhodopseudomonas sphaeroides and rps. capsulata and chromatium vinosum) are discussed. we conclude that there are probably ...1978110568
membrane potential and reconstitution. 1979110998
[conformational regulation of functional activity of photosynthetic membranes of purple bacteria].in reaction centres of photosynthetic membranes of r, rubrum the efficiency of redox interactions of the photoreduced primary electron acceptor with secondary acceptors and photooxidized bacteriochlorophyll has a marked and reversible dependence on temperature over the range from -20 degrees to -80 degrees. similar temperature dependences were observed for correlation times of the rotational diffusion of a spin probe bound to the hydrophobic region of the membrane and of a spin label bound to sh ...1979111034
[use of urea by purple bacteria].strains of purple sulfur bacteria (chromatium minutissimum, ectothiorhodospira shaposhnikovii, thiocapsa roseopersicina, lamprobacter modestohalophilus) and nonsulfur bacteria (rhodopseudomonas palustris, rh. spheroides, rhodospirillum rubrum) grow in media containing urea as a source of nitrogen at concentrations from 0.5 to 5.0%. they can also utilize the carbon of urea and thus grow in the absence of bicarbonate. urea is decomposed by all the studied purple bacteria with the participation of ...1979112359
[application of polarography to studies on redox systems in bio-membranes: especially on photosynthetic electron transport system in chromatophore membrane from photosynthetic bacterium (author's transl)]. 1979112648
[functional organization of the electron transport chain of rhodospirillum rubrum chromatophores in the absence of an exogenous electron donor]. 1979113038
coupling factor adenosine triphosphatase-complex of rhodospirillum rubrum. isolation of an oligomycin-sensitive ca2+, mg2+--atpase. 1977142656
photoreaction center of photosynthetic bacteria. 1. further chemical characterization of the photoreaction center from rhodospirillum rubrum.the photoreaction center from rhodospirillum rubrum contains about 90% protein, 6% pigment, mere traces of lipids, and no cytochromes. it also contains at least 1 mol of ubiquinone and 1 iron atom per mol. its three-component polypeptide chains were isolated by preparative electrophoresis, and their molar stoichiometry was established as 1:1:1. the amino acid composition of the photoreaction center from strain s1 and from its subunits is reported. the protein as a whole contains about 65% nonpol ...1979114212
inhibition of the proton-translocating adenosine triphosphatase from chromatophores of photosynthetic bacteria by free bivalent cations and adenosine triphosphate [proceedings]. 1977144630
resolution and reconstitution of rhodospirillum rubrum pyridine dinucleotide transhydrogenase: chemical modification with n-ethylmaleimide and 2,4-pentanedione. 197939595
photoreaction center of photosynthetic bacteria. 2. size and quaternary structure of the photoreaction centers from rhodospirillum rubrum strain g9 and from rhodopseudomonas sphaeroides strain 2.4.1.the photoreaction center from rhodospirillum rubrum strain g9 binds about 6 times as much sodium dodecyl sulfate as certain proteins commonly used as molecular weight markers for sodium dodecyl sulfate--polyacrylamide gel electrophoresis. this presumably explains the apparent discrepancy between the molecular weight of the photoreaction center determined by electrophoresis (76 000) and its minimal molecular weight (87 000). the molecular weight of the photoreaction center solubilized with triton ...1979114213
nitrogenase from rhodospirillum rubrum. relation between 'switch-off' effect and the membrane component. hydrogen production and acetylene reduction with different nitrogenase component ratios.nitrogenase activity of 'membrane-free' extracts, produced from nitrogen-starved rhodospirillum rubrum to which 4 mm nh4+ had been added is only about 10% of the activity in the control. the activity could be restored to 80% by including the membrane component, earlier found to activate r. rubrum nitrogenase, in the reaction mixture. the relation between this 'switch-off/switch-on' effect and the function of the membrane component is discussed. hydrogen production catalyzed by r. rubrum nitrogen ...1979114217
a quantitative assay for bacterial rna polymerases. 1979114520
activation and regulation of ribulose bisphosphate carboxylase-oxygenase in the absence of small subunits.ribulose 1,5-bisphosphate carboxylase from rhodospirillum rubrum requires co2 and mg2+ for activation of both co2, both the carboxylase and oxygenase activities are stimulated by 6-phoshpo-d-gluconate, fructose 1,6-bisphosphate, 2-phosphoglycolate, 3-phosphoglycerate, nadph, and fructose 6-phosphate. the carboxylase activity is not activated by ribose 5-phosphate. the substrate, ribulose bisphosphate, neither activates nor inhibits the co2 and mg2+ activation of this enzyme. activation by co2 an ...1979114521
changes in the acyl lipid composition of photosynthetic bacteria grown under photosynthetic and non-photosynthetic conditions.the acyl lipids and their constituent fatty acids were studied in the photosynthetic bacteria rhodospirillum rubrum, rhodopseudomonas capsulata and rhodopseudomonas sphaeroides, which were grown under photosynthetic and non-photosynthetic conditions. the major lipids were found to be phosphatidylethanolamine, phosphatidylglycerol and cardiolipin in each bacterium. the two rhodopseudomonas species also contained significant quantities of phosphatidylcholine. other acyl lipids accounted for less t ...1979115463
differential effects of metal ions on rhodospirillum rubrum ribulosebisphosphate carboxylase/oxygenase and stoichiometric incorporation of hco3- into a cobalt(iii)--enzyme complex.mg2+ or mn2+ ions supported both the carboxylase and oxygenase activities of the rhodospirillum rubrum ribulosebisphosphate carboxylase/oxygenase. for the carboxylase reaction, mn2+ supported 25% of the maximum activity obtained with mg2+; oxygenase activity, however, was twice as great with mn2+ as compared to that with mg2+. a further differential effect was obtained with co2+. co2+ did not support carboxylase activity and, in fact, was a strong inhibitor of mg2+-dependent carboxylase activity ...1979115489
extracellular hydrogenase from photosynthetic bacterium, rhodospirillum rubrum.with rhodospirillum rubrum, hydrogenase was found to exist partly as an extracellular enzyme in the culture medium. after 4-day cultivation, the total activity and the specific activity of the enzyme in the medium were about 10 times and 230 times as high as those in the crude extract obtained from disrupted cells. the time course for the production of hydrogenase during cultivation was studied.1979115852
two regimens of electrogenic cyclic redox chain operation in chromatophores of non-sulfur purple bacteria. a study using antimycin a.antimycin a causes a biphasic suppression of the light-induced membrane potential generation in rhodospirillum rubrum and rhodopseudomonas sphaeroides chromatophores incubated anerobically. the first phase is observed at low antibiotic concentrations and is apparently due to its action as a cyclic electron transfer inhibitor. the second phase is manifested at concentrations which are greater than 1--2 mum and is due to uncoupling that may be connected with an antibiotic-induced dissipation of th ...1979116681
ribulose bisphosphate carboxylases from chromatium vinosum and rhodospirillum rubrum and their role in photosynthetic carbon assimilation. 1978106836
characterization of a succinate dehydrogenase complex solubilized from the cytoplasmic membrane of bacillus subtilis with the nonionic detergent triton x-100.a succinic dehydrogenase (sdh) complex has been purified from triton x-100-solubilized membranes from bacillus subtilis by precipitation with specific antibody. radioactively labeled precipitated complex was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by autoradiography of the gels. the complex contained equimolar amounts of three polypeptides with approximate molecular weights of 65,000, 28,000, and 19,000. five succinic dehydrogenase-negative mutants, belongi ...1979108258
photooxidase activity of rhodospirillum rubrum chromatophores and reaction center complexes. the role of non-cyclic electron transfer in generation of the membrane potential. 1979109117
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