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unidirectional inhibition of phosphoenolpyruvate carboxykinase from rhodospirillum rubrum by atp.the kinetic and regulatory properties of partially purified phosphoenolpyruvate (pep) carboxykinase (ec 4.1.1.3.2) from rhodospirillum rubrum were studied. the enzyme was active with guanosine- and inosinephosphates and must thus be classified as gtp (itp): oxaloacetate carboxylase (transphosphorylating.) in the direction of oxaloacetate-foramtion, the enzyme was strongly inhibited by atp (ki = 0.03 mm). itp, utp, ctp, and gtp were less inhibitory. the inhibition was competitive with respect to ...1976816325
a spin-label study of biological membranes with special emphasis on calcium-induced lateral phase separation. 1976176878
regulatory properties of the citrate synthase from rhodospirillum rubrum.citrate synthase, purified 600-fold from rhodospirillum rubrum, is activated by kcl and inhibited by atp and nadh; the effect of the latter inhibitor is completely counteracted by amp and partially counteracted by kcl.1976178526
[polyphosphate biosynthesis in rhodospirillum rubrum chromatophores].the chromatophores of rhodospirillum rubrum were found to synthesize in the light not only atp and pyrophosphate but also high molecular weight polyphosphates. biosynthesis of all studied compounds was inhibited by antimycin a, an inhibitor of the electron-transport photosynthetic chain. synthesis of high molecular weight polyphosphates is stimulated, while that of pyrophosphate is inhibited, in the conditions providing intensive synthesis of atp (in the presence of adp and in the absence of oli ...1976180387
polarographic studies in presence of triton x-100 on oxidation-reduction components bound with chromatophores from rhodospirillum rubrum.polarographic studies on oxidation-reduction components bound with chromatophores from rhodospirillum rubrum were carried out at 24 degrees. 1. using a carbon-paste electrode as the working electrode, polarographic waves characteristic of oxidation-reduction components were observed in the presence, but not in the absence of triton x-100; these waves were therefore measured in the presence of the detergent. 2. at least two kinds of oxidation-reduction components were detectable, having different ...1976181368
preparation of cytochrome c2 from rhodospirillum rubrum. 1976182031
ribulose 1,5-diphosphate carboxylase and cholorobium thiosulfatophilum.1. cell-free extracts of the photosynthetic bacterium cholorobium thiosulfatophilum, strains 8327 and tassajara, were assayed for ribulose 1,5-diphosphate (rudp) carboxylase and phosphoribulokinase--the two enzymes peculiar to the reductive pentose phosphate cycle. 2. rudp carboxylase was consistently absent in strain 8327. the tassajara strain showed a low rudp-dependent co2 fixation activity that was somewhat higher in cells following transatlantic air shipment than in freshly grown cells. the ...1976183616
the early formation of the photosynthetic apparatus in rhodospirillum rubrum.the time dependent assembly of the photosynthetic apparatus was studied in rhodospirillum rubrum after transfer of cells growing aerobically in the dark to low aeration. while bacteriochlorophyll (bchl) cellular levels increase continuously levels of soluble cytochrome c2 do not change significantly. absorption spectra of membranes isolated at different times after transfer reveal that incorporation of carotenoids lags behind incorporation of bchl. however, a carotenoid fraction exhibiting spect ...1976182100
coupling factor adenosine-5'-triphosphatase from rhodospirillum rubrum: a simple and rapid procedure for its purification.when photosynthetic membranes from rhodospirillum rubrum, devoid of loosely bound small molecules and proteins, were passed through a french-pressure cell, the enzyme adenosine-5'-triphosphatase (ec 3.6.1.3.) (atpase) was released into the soluble fraction. the solubilized atpase was purified to homogeneity. in many respects it behaved like the enzyme purified by other workers, but it also hydrolyzed mg-atp with a small, but significant rate. furthermore, it was much more stable. maximal restora ...1976183408
investigation of the structure of the reaction center in photosynthetic bacteria by optical detection of triplet state magnetic resonance. 1976183778
thermodynamic properties of the reaction center of rhodopseudomonas viridis. in vivo measurement of the reaction center bacteriochlorophyll-primary acceptor intermediary electron carrier.the thermodynamic properties of redox components associated with the reaction center of rhodopseudomonas viridis have been characterized with respect to their midpoint potentials and relationship with protons. in particular a midpoint potential for the intermediary electron carrier acting between the reaction center bacteriochlorophyll and the primary acceptor has been determined. the rationale for this measurement was that the light-induced triplet/biradical epr signal would not be observed if ...1976183815
kinetics of populating and depopulating of the components of the photoinduced triplet state of the photosynthetic bacteria rhodospirillum rubrum, rhodopseudomonas spheroides (wild type), and its mutant r-26 as measured by esr in zero-field.optically detected esr spectra in zero magnetic field of the triplet state of three photosynthetic bacteria are presented. the zero field splitting parameters [d] and [e] and the widths of the resonances show small but significant differences for the three bacteria. the resonance lines are inhomogeneously broadened as demonstrated by hole-burning experiments. the populating probabilities and depopulating rates for the triplet sublevels have been measured. the populating kinetics are very similar ...1976183816
the effect of transfer from low to high light intensity on electron transport in rhodospirillum rubrum membranes.the effects of transfer from low to high light intensity on membrane bound electrontransport reactions of rhodospirillum rubrum were investigated. the experiments were performed with cultures which did not form bacteriochlorophyll (bchl) for about two cell mass doublings during the initial phase of adaptation to high light intensity. lack of bchl synthesis causes a decrease of bchl contents of cells and membranes. also, the cellular amounts of photosynthetically active intracytoplasmic membranes ...1976185976
function of three cytochromes in photosynthesis of whole cells of rhodospirillum rubrum as studied by flash spectroscopy. evidence for two types of reaction center.1. changes in the absorption spectrum induced by 10-mus flashes and continuous light of various intensities were studied in whole cells of rhodospirillum rubrum in the presence and absence of 2-n-heptyl-4-hydroxyquinoline-n-oxide(hoqno) and antimycin a. 2. three cytochromes, c-420 (cytochrome c2), c-560 (cytochrome b) and c-428 were photoactive and gamma and alpha peaks at 420 and 550, 428 and 560, and 428 and 551 nm, respectively; they were photooxidized following the flash with half times of 0 ...1976186114
magnetophotoselection applied to the triplet state observed by epr in photosynthetic bacteria. 1976187200
the control of the adenosine triphosphatase of rhodospirillum rubrum chromatophores by divalent cations and the membrane high energy state.1. the rate of atp hydrolysis, catalysed by rhodospirilum rubrum chromatophores is accelerated by low concentrations and inhibited by high concentrations of uncoupling agent. 2. the inhibition at high concentrations of uncoupling agent is potentiated by the presence of free magnesium ions. at low uncoupler concentrations magnesium has no effect on the rate of atp hydrolysis. 3. inhibition of atp hydrolysis by high concentrations of uncoupling agent and free magnesium ions is reversed by illumina ...1976129328
coupling factors atpases from photosynthetic bacteria. 1976134033
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
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
the primary acceptor of bacterial photosynthesis: its operating midpoint potential? 19764013
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
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
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
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
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
base competition of dna isolated from thiobacillus ferrooxidans grown on different substrates.the present study indicates some anomalies with respect to the dna base composition of thiobacillus ferrooxidans when it is cultured on different substrates. the % gc of the dna of this bacterium has been calculated by three different methods (melting temperature, cscl density gradient centrifugation and ultra-violet absorbancy ratios) using escherichia coli and rhodospirillum rubrum as references. the main values for t. ferrooxidans grown on ferrous iron, chalcopyrite and lead sulfide concentra ...1976981743
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
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
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
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
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
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
interconversion of two kinetically distinct states of the membrane-bound and solubilised h+-translocating atpase from rhodospirillum rubrum. 197715868
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
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
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
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
[spectral position of the principal absorption band of pigment complex p870 and the kinetics of photo-induced oxidoreductions in the reaction centers and chromatophores of purple bacteria with preparations at different temperatures and having different degrees of hydration].in isolated photosynthetic reaction centres of rps. spheroides and chromatophores r. rubrum the spectral position of the longest wavelength absorption band of p870, effectiveness of electron removal from the photochemical pair (p870 -- primary electron acceptor, a1) and the rate constant for recombination of photooxidized p870 with photoreduced a1 undergo marked and fully reversible changes over the temperature interval from +20 to -70 degrees. dehydration of the samples has the effect similar t ...1977109746
[characterization of lipase activity in a yeast of the genus rhodotorula (rh. rubra)].lipase activity of whole cells of rh. rubra has been localized in a particular fraction rich in walls and in isolated cell walls. the enzyme activity has been determinated with olive oil and the triglyceride fraction of olive oil as substrats. gas chromatography of fatty acids and triglycerides isolated after enzyme hydrolysis shows that the action of rh. rubra is not only limited to a simple hydrolysis of the substrate. the triglyceridase activity level is dependent of the phosphate content of ...1977143999
[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
coupling factor adenosine triphosphatase-complex of rhodospirillum rubrum. isolation of an oligomycin-sensitive ca2+, mg2+--atpase. 1977142656
near-infrared magnetic circular dichroism of cytochrome c'.the near-infrared magnetic circular dichroism (mcd) of rhodospirillum rubrum, chromatium vinosum, and rhodopseudomonas palustris cytochromes c' are reported. the spectra of the reduced protein are very similar to those of deoxymyoglobin. the spectra of the oxidized proteins in the pd range 1-13 can be analyzed on the basis of four species a, b, c, and d. the existence of nine species, reported in a recent electron paramagnetic resonance study, is not substantiated. the mcd spectra support the as ...1977192272
stereochemistry of the porphyrin-protein bond of cytochrome c. stereochemical comparison of rhodospirillum rubrum, yeast, and horse heart porphyrins c.porphyrins c have been obtained from rhodospirillum rubrum cytochrome c2, yeast cytochrome c, and horse heart cytochrome c and compared using proton magnetic resonance and circular dichroism. identity of the spectra establishes that chemically and stereochemically the three porphyrins c are identical. since the stereochemistry of the porphyrin alpha-thioether linkage is not affected in the conversion to porphyrin c, the stereochemistry at the porphyrin alpha-thioether bonds among the correspondi ...1977192273
phototaxis and membrane potential in the photosynthetic bacterium rhodospirillum rubrum.cells of the photosynthetic bacterium rhodospirillum rubrum cultivated anaerobically in light show phototaxis. the behavior of individual cells in response to the phenomenon is reversal(s) of the swimming direction when the intensity of the light available to them abruptly decreases. the tactic response was inhibited by antimycin, an inhibitor of the photosynthetic electron transfer system. the inhibitory effect of antimycin was overcome by phenazine methosulfate. motility of the cells was not i ...1977194880
[isolation and characterization of a membrane-bound pyruvate dehydrogenase complex from the phototrophic bacterium rhodospirillum rubrum (author's transl)].the pyruvate dehydrogenase complex from the photosynthetic bacterium rhodospirillum rubrum was associated with the membrane fraction both in heterotrophically and photosynthetically grown cells. the complex was separated from the membranes and partially purified by precipitation with mgso4 and gelfiltration through sepharose 4b. the purified complex had a specific activity of 1.5-2mumol/min-mg protein and contained the following partial activities: pyruvate dehydrogenase (ec 1.2.4.1), dihydrolip ...1977195415
structure and function of cytochromes c. 1977197877
mössbauer studies of cytochrome c' from rhodospirillum rubrum.cytochrome c' from rhodospirillum rubrum has been investigated in the ferric form with mössbauer and epr spectroscopy. in the ph range from 6 to 9.5, three species are observed which belong to two ph-dependent equilibria with pk values near 6 and 8.5. the pk = 6 transition is resolved only with high-field mössbauer spectroscopy. for the three species we have determined the zero-field splitting parameters and the hyperfine coupling constants. the data were fitted to a spin hamiltonian which takes ...1977199273
isolation and characterization of bound ion-sulfur proteins from bacterial photosynthetic membranes. i. ferredoxins iii and iv from rhodospirillum rubrum chromatophores. 1977199587
isolation and characterization of bound ion-sulfur proteins from bacterial photosynthetic membranes. ii. succinate dehydrogenase from rhodospirillum rubrum chromatophores. 1977199588
comparative kinetic-ionic strength study of two differently charged cytochrome c: effects are limited to overall charge. 1977202274
inhibition of the proton-translocating adenosine triphosphatase from chromatophores of photosynthetic bacteria by free bivalent cations and adenosine triphosphate [proceedings]. 1977144630
coupling factor atpase complex of rhodospirillum rubrum. purification and properties of a reconstitutively active single subunit. 1977144735
a novel electron paramagnetic resonance signal associated with the 'primary' electron acceptor in isolated photochemical reaction centers of rhodospirillum rubrum. 1977200472
reduction kinetics of bacterial cytochromes c2. 1977202201
preliminary crystallographic data for cytochromes c' of rhodopseudomonas capsulata and rhodospirillum molischianum. 1977204789
reaction of ribulosebisphosphate carboxylase from rhodospirlilum rubrum with the potential affinity label 3-bromo-1,4-dihydroxy-2-butanone 1,4-biphosphate. 1977403917
isolation and characterization of an organic solvent soluble polypeptide component from photoreceptor complexes of rhodospirillum rubrum.an organic solvent soluble polypeptide has been isolated from photoreceptor complexes and chromatophores of rhodospirillum rubrum. after extraction of the protein from lyophilized samples with 1:1 chloroform-methanol, it was purified by column chromatography. its isoelectric point determined by isoelectric focusing was 7.10. when analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the purified polypeptide ran as a single band of an apparent molecular weight of 12 000. however, ...1977402930
the effect of electron donors and acceptors on light-induced absorbance changes and photophosphorylation in rhodospirillum rubrum chromatophores.light-induced difference spectra between 400 and 640 nm of rhodospirillum rubrum chromatophores were performed in the presence and absence of exogenous electron donor/acceptor systems and compared with the chemical oxidation spectrum. the results indicate that the component previously defined as p430 is not a unique entity but rather represents different species, or a mixture of species, under various conditions. under all conditions in which the reaction center bacteriochlorophyll is reversibly ...1977411652
isolation of the membrane-bound hydrogenase from rhodospirillum rubrum. 1977409403
necessity of a membrane component for nitrogenase activity in rhodospirillum rubrum.acetylene reduction catalyzed by nitrogenase from rhodospirillum rubrum has low activity and exhibits a lag phase. the activity can be increased by the addition of a chromatophore membrane component and the lag eliminated by preincubation with this component, which can be solubilized from chromatophores by treatment with nacl. it is both trypsin- and oxygen-sensitive. titration of the membrane component with nitrogenase and vice versa shows a saturation point. the membrane component interacts sp ...1977410446
evidence for monomeric bacteriochlorophyll in p800 of the photoreaction center from rhodospirillum rubrum.to find out whether weak or strong coupling exists between the bacteriochlorophyll molecules of the photoreaction center, the relative efficiency of energy transfer to p870 was measured at 795 nm and at 808 nm, at room temperature and at 77 degrees k. at room temperature, both relative efficiencies are close to 100%. however, at 77 degrees k, 795 nm light has a quantum efficiency of 76% and 808 nm light has an efficiency of 87%. these results confirm the fact that p800 is formed of at least one ...1977403944
localisation of the subunits of the photosynthetic reaction centers in the chromatophore membrane of rhodospirillum rubrum.reaction centers were isolated with the detergent lauryl dimethyl amine oxide from chromatophore membranes of rhodospirillum rubrum. the subunit composition of these reaction centers is similar to the one obtained from rhodopseudomonas spheroides: three subunits with the molecular weights of 21 000, 24 000 and 29 000. reaction centers prepared from chromatophores labeled with 131i were heavely labeled in their large subunit (h). the smaller subunits (l and m) contained only little label. sonicat ...1977403945
[carbonic anhydrase activity of phototropic bacteria].the activity of carboanhydrase was assayed in seven species of phototrophous bacteria: three species of the rhodospirillaceae genus, three species of the chromatiaceae genus, and one species of the chlorobiaceae genus. the activity of carboanhydrase was found in five species among seven. it decreased on passing from photoautotrophous to photoheterotrophous conditions of growth, and then to dark heterotrophous conditions, which correlated with the activity of the calvin cycle in the bacteria. no ...1977408582
structural aspects of the reaction center of photosynthetic bacteria calculated from triplet state zero-field splittings. 1977410658
excitation trapping by different states of photosynthetic reaction centres. 1977410664
reduction of adenylylsulfate and 3'-phosphoadenylylsulfate in phototrophic bacteria.extracts of 14 species of phototrophic bacteria, partly grown with different sulfur compounds, were tested for their ability to form volatile sulfur compounds from adenylylsulfate (aps) and 3'-phosphoadenylylsulfate (paps). the rhodospirillum species showed marked activities with both aps and paps while the rhodopseudomonas species seem to prefer paps. the chromatiaceae exhibited the strongest activities with aps, whereas chlorobium limicola had equally high activity with paps.1977408177
demonstration of two 3,3'-diaminobenzidine oxidation reactions associated with photosynthetic membranes in anaerobic light-grown rhodospirillum rubrum.photosynthetic membranes of anaerobic light-grown rhodospirillum rubrum oxidized 3,3'-diaminobenzidine. when glutaraldehyde-treated cells were exposed to 3,3'-diaminobenzidine in the light aerobically, the oxidation appeared to occur by two systems. one reaction was stimulated by white light and the second required molecular oxygen. the o2-dependent activity was inhibited by kcn.1977410873
isolation of an iron-molybdenum cofactor from nitrogenase.a method for the isolation of an iron-molybdenum cofactor (femoco) from component i of nitrogenase is described. this method is used to isolate femoco from aerobic, anaerobic, facultative, and photosynthetic nitrogen-fixing organisms. the fe/mo ratio in the femoco from azotobacter vinelandii and clostridium pasteurianum is 8:1. the femoco contains six atoms of acid-labile sulfide per eight fe atoms. crystalline component i from a. vinelandii contains 2 mo, 33 fe, and 27 acid-labile sulfide atoms ...1977410019
sensitive measurement of flash induced photophosphorylation in bacterial chromatophores by firefly luciferase. 1977408188
ubiquinone and photochemical activity in rhodospirillum rubrum. 1977403533
mechanisms of co2 fixation in bacterial photosynthesis studied by the carbon isotope fractionation technique.the carbon isotope discrimination properties of a representative of each of the three types of photosynthetic bacteria chlorobium thiosulfatophilum, rhodospirillum rubrum and chromatium and of the c3-alga chlamydomonas reinhardii were determined by measuring the ratio of 13co2 to 12co2 incorporated during photoautotrophic growth. 2. chromatium and r. rubrum had isotope selection properties similar to those of c3-plants, whereas chlorobium was significantly different. 3. the results suggest that ...1977402896
linear dichroism of light-induced absorbance changes of reaction centers of rhodospirillum rubrum. 1977405251
simple equipment for the growth of photosynthetic bacteria. 1977406256
purification, molecular properties, and amino acid composition of the subunits of rhodospirillum rubrum succinate dehydrogenase. 1977406851
isolation and characterization of a bacteriochlorophyll-associated chromatophore protein from rhodospirillum rubrum g-9. 1977408189
homoserine dehydrogenase: spontaneous reactivation by dissociation of p-mercuribenzoate from an inactive enzyme--p-mercuribenzoate complex.incubation of rhodospirillum rubrum homoserine dehydrogenase (l-homoserine:nad+ oxidoreductase, ec 1.1.1.3) with p-mercuribenzoate (pmb) in the presence of 0.2 m kcl and 2 mm l-threonine resulted in complete loss of enzyme activity. upon removal of excess pmb, kcl, and l-threonine, a time-dependent recovery of enzyme activity was observed in 25 mm phosphate/i mm edta buffer, ph 7.5. circular dichroism studies indicated that the transition from inactive to reactivated form of the enzyme was accom ...1977270718
comparison of the electrochemical proton gradient and phosphate potential maintained by rhodospirillum rubrum chromatophores in the steady state. 1977402116
physiological studies of spirillum lipoferum. 1977411476
amino acid sequence of desulfovibrio vulgaris flavodoxin.the complete amino acid sequence for the 148-amino acid flavodoxin from desulfovibrio vulgaris was determined to be: h3n+-met-pro-lys-ala-leu-ile-val-tyr-gly-ser-thr-thr-gly-asn-thr-glu-tyr-thr-ala-glu-thr-ile-ala-arg-glu-leu-ala-asn-ala-gly-tyr-glu-val-asp-ser-arg-asp-ala-ala-ser-val-glu-ala-gly-gly-leu-phe-glu-gly-phe-asp-leu-val-leu-leu-gly-cys-ser-thr-trp-gly-asp-asp-ser-ile-glu-leu-gln-asp-asp-phe-ile-pro-leu-phe-asp-ser-leu-glu-glu-thr-gly-ala-gln-gly-arg-lys-val-ala-cys-phe-gly-cys-gly-as ...1977402366
a novel pathway for l-citramalate synthesis in rhodospirillum rubrum.when [14c]propionate was incubated with a cell-free extract of rhodospirillum rubrum in the presence of glyoxylate, atp, coa, mg2+, and mn2+, radioactivity was incorporated into mesaconate (msa) as well as into beta-methylmalate (mma) and citramalate (cma). msa was suggested to be an intermediate of the conversion of mma to cma based on the following observations. (i) when non-labeled msa was added to the cma-forming reaction system, radioactivity was trapped in msa. (ii) when msa was incubated ...1977405381
effects of long-term treatment with acetylene on nitrogen-fixing microorganisms.long periods of experimental incubation with acetylene led to a multifold enhancement of acetylene-reducing activity in anabaena cylindrica, anabaenopsis circularis, rhodospirillum rubrum, and azotobacter vinelandii. rates of acetylene reduction showed a gradual increase and reached a peak after 2 to 6 h of continuous incubation under acetylene. thereafter, enzyme activity rapidly declined. a similar enhancement of ethylene production was observed when pretreatment with acetylene was interrupted ...1977413480
biological activities of lipopolysaccharides and lipid a from rhodospirillaceae.the lipopolysaccharides and free lipid a from several strains of rhodospirillaceae were assayed comparatively with those of enterobacteriaceae in a number of biological tests. free lipid a's from rhodopseudomonas gelatinosa and rhodospirillum tenue exhibited strong serological cross-reactions with each other and with free lipid a from salmonella. lipid a's from rhodopseudomonas viridis and rhodopseudomonas palustris, although cross-reacting with each other, did not do so with either the lipid a ...1977558961
energy-linked nicotinamide nucleotide transhydrogenases. 1977409434
isolation of a photosynthetic strain of rhodospirillum rubrum with an altered reaction center. 1977409348
[light-induced oxygen uptake by chromatophores and subchromatophore pigment-protein complexes of rhodospirillum rubrum].chromatophores of r. rubrum incubated with electron donors, e. g. reduced diaminodurene, tmpd, phenazine methosulphate, cytochrome c or ferrocyanide, are able to catalyze o2 uptake upon illumination. this process is inhibited by o-phenanthroline as well as upon extraction of quinones from chromatophores, but not by antimycin a, rotenone or cn-. the o2 uptake sensitive to the action of o-phenanthroline is also observed in the illuminated subchromatophore p870 reaction center complexes and reactio ...1977412525
structure and function of carotenoids in the photoreaction center from rhodospirillum rebrum. 1977409431
binding and reaction studies with adenine nucleotides on purified coupling factor from rhodospirillum rubrum.equilibrium binding studies with atpase isolated from rhodospirillum rubum chromotophores have been carried out using gel filtration. binding experiments with variable concentrations of [14c]adp show a biphasic saturation curve. with a parameter fitting computer program the dissociation constants for two distinct binding sites are determined as 7 x 10(-6) and 9 x 10(-5) m, respectively. the enzyme-bound radioactivity is recovered as adp (80-90%), and the rest is converted to amp and atp. in the ...197718265745
carbon isotope fractionation by ribulose-1,5-bisophosphate carboxylase from various organisms.carbon isotope fractionation by structurally and catalytically distinct ribulose-1,5-bisphosphate carboxylases from one eucaryotic and four procaryotic organisms has been measured under nitrogen. the average fractionation for 40 experiments was -34.1 per thousand with respect to the delta(13)c of the dissolved co(2) used, although average fractionations for each enzyme varied slightly: spinach carboxylase, -36.5 per thousand; hydrogenomonas eutropha, -38.7 per thousand; agmenellum quadruplicatum ...197816660363
direct measurement of pure absorbance spectra of living phototrophic microorganisms.the pure absorbance of turbid cell suspensions of various phototrophic microorganisms were determined by collecting the scattered light. a conventional spectrophotometer was used, equipped with an intergrating sphere as receiver unit, which allowed precise measurements of the absorbance in the range from zero to 0.1. in the wavelength range 300--1100 nm, where photosynthesis occurs, light scattered only once by a bacterial cell retains predominantly the forward direction. this allows measurement ...1978626755
modification of rhodospirillum rubrum ribulose bisphosphate carboxylase with pyridoxal phosphate. 2. stoichiometry and kinetics of inactivation.rhodospirillum rubrum ribulose bisphosphate carboxylase contains two high affinity binding sites for pyridoxal phosphate and two catalytic sites per dimer. however, pyridoxal phosphate binding at only one site is sufficient for inactivation of both catalytic sites. in the presence of 20 mm bicarbonate, 10 mm magnesium, and pyridoxal phosphate, the rates of inactivation and schiff base formation are pseudo-first-order and show saturation kinetics. these observations provide additional evidence th ...1978418800
the photoproduction of h2 and nh4 fixed from n2 by a derepressed mutant of rhodospirillum rubrum.a mutant of rhodospirillum rubrum has been isolated, after mutagenesis with nitrosoguanidine, which is characterized by its inability to grow in the light on malate-minimal media with exogenous ammonia or alanine, poor growth on glutamine and vigorous growth on glutamate. this mutant produces low levels of a key nh+4 assimilation enzyme, glutamate synthase (nadph-dependent). it also exhibits significant derepression of nitrogenase biosynthesis in the presence of ammonia or alanine, being 15% der ...1978418808
quantum yield and image contrast of bacteriochlorophyll monolayers in photoelectron microscopy.the photoelectron quantum yield spectrum of bacteriochlorophyll agg (bchl a ) from rhodospirillum rubrum was determined in order to evaluate the possibility of mapping photoreceptor distribution and organization in bacterial chromatophores. the quantum yield is on the order of 1 x 10(-3) electrons/incident photon at 180 nm and decreases to 2.5 x 10(-5) electrons/incident photon at 230 nm. photoelectron micrographs confirm the high contrast predicted between monolayers of bchl a against a lipid b ...1978630040
structural studies on the d-arabinose-containing lipid a from rhodospirillum tenue 2761.structural studies carried out on the isolated free lipid a of rhodospirillum tenue 2761 revealed a new type of structure for this lipid. the lipid a backbone of 1',6-linked glucosamine disaccharide (central disaccharide) is substituted by three different sugar residues: the non-reducing end of the disaccharide by 4-amino-4-deoxy-l-arabinose 1-phosphate and its reducing end glycosidically by d-arabinofuranose 1-phosphate; further, the reducing glucosamine of the disaccharide is branched to a thi ...1978639795
purification of (4fe-4s)1--2--ferredoxins (high-potential iron--sulfur proteins) from bacteria. 1978713842
inactivation of ribulosebisphosphate carboxylase by modification of arginyl residues with phenylglyoxal.phenylglyoxal rapidly and completely inactivates spinach and rhodospirillum rubrum ribulosebisphosphate carboxylases. inactivation exhibits pseudo-first-order kinetics and a reaction order of approximately one for both enzymes, suggesting that modification of a single residue per protomeric unit suffices for inactivation. loss of enzymic activity is directly proportional to incorporation of [14c]phenylglyoxal until only 30% of the initial activity remains. for both enzymes, extrapolation of inco ...1978728421
dna homology studies on nocardia and rhodococcus strains.the genetic homogeneity of nocardia amarae, nocardia autotrophica and rhodococcus strains and the relationship among these groups of microorganisms have been studied using the dna reassociation method. strains belonging to n. amarae and n. autotrophica form genetically homogeneous groups. distinct differences have been found out among rhodococcus strains.1978749779
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