PMID(sorted descending)
[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, dihydrolip ...1977195415
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
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
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
magnetophotoselection applied to the triplet state observed by epr in photosynthetic bacteria. 1976187200
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
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
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
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
investigation of the structure of the reaction center in photosynthetic bacteria by optical detection of triplet state magnetic resonance. 1976183778
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
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 (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
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
preparation of cytochrome c2 from rhodospirillum rubrum. 1976182031
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
[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
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
a spin-label study of biological membranes with special emphasis on calcium-induced lateral phase separation. 1976176878
the photogeneration of superoxide by isolated photoreaction center from rhodospirillum rubrum. 1975173311
amino acid sequence of cytochrome c' from the purple photosynthetic bacterium rhodospirillum rubrum s1.the amino acid sequence of cytochrome c' from the purple photosynthetic bacterium rhodospirillum rubrum s1 has been determined and is consistent with homology to cytochrome c' from the nonphotosynthetic bacterium alcaligenes sp. ncib 11015. there is 29% identity in the chosen alignment of these two proteins. r. rubrum cytochrome c' is composed of a single peptide chain of 126 amino acid residues with a single heme covalently bound near the cooh terminus. there is no sequence similarity to mitoc ...1975172499
characterization of two soluble ferredoxins as distinct from bound iron-sulfur proteins in the photosynthetic bacterium rhodospirillum an earlier investigation (shanmugam, k. t., buchanan, b. b., and arnon, d. i. (1972) biochim. biophys. acta 256, 477-486) the extraction of ferredoxin from rhodospirillum rubrum cells with the aid of a detergent (triton x-100) and acetone revealed the existence of two types of ferredoxin (i and ii) and led to the conclusion that both are membrane-bound. in the present investigation, ferredoxin and acid-labile sulfur analyses of photosynthetic membranes (chromatophores) and soluble protein ext ...1975172494
role of ubiquinone-10 in electron transport system of chromatophores from rhodospirillum rubrum.the role of ubiquinone-10 in the activities for the reduction of free cytochrome c2 and bound cytochrome cc' by succinate was studied with chromatophores from a blue-green mutant (g-9) of rhodospirillum rubrum. 1. by a single extraction with isooctane, approximately 90% of ubiquinone-10 was easily removed from the chromatophores. in the extracted chromatophores, the activity for succinate-cytochrome c2 reduction decreased to 5-10% of the original activity. this depressed activity was mostly rest ...1975172493
letter: optically detected zero-field magnetic resonance studies of the photoexcited triplet state of the photosynthetic bacterium rhodosopirillum rubrum. 1975171297
conformational energy refinement of horse-heart ferricytochrome c.the reported x-ray structure of horse-heart ferricytochrome c has been refined by conformational energy calculations, using a three-stage computational procedure. in stage i, the atomic positions are adjusted to conform to idealized bond lengths and bond angles characteristic of small amino acid derivatives, while yet remaining as close as possible to the x-ray coordinates. in stage ii, atomic overlaps are eliminated by adjusting the backbone and side-chain dihedral angles to minimize the nonbon ...1975169878
enzymes of glycollate formation and oxidation in two members of the rhodospirillacae (purple non-sulphur bacteria).1. phototrophic cultures of rhodomicrobium vanielii do not excrete glycollate when gassed anaerobically with nitrogen plus carbon dioxide, although the addition of alpha-hydroxy-2-pyridine methanesulphonate (hpms) results in the excretion of a trace amount of glycollate. the inclucion of low amounts of oxygen in this gas mixture results in marked glycollate excretion, higher rates occurring in the presence of hpms. 2. cell extracts of rhodomicrobium vannielii, and also of rhodospirillum rubrum, ...1975168831
[photoformation of free radicals in the system bacteriochlorophyll--p-benzoquinone]. 1975166805
models for antenna and reaction center chlorophylls. 1975166592
influence of light on the epr-detectable, electron transport components in whole cell rhodospirillum rubrum. 1975165557
separation of respiratory reactions in rhodospirillum rubrum: inhibition studies with 2-hydroxydiphenyl.1. respiration of chemotrophically and phototrophically grown rhodospirillum rubrum is inhibited by 2-hydroxydiphenyl. 2. membrane-bound nadh oxidase and nadh: cytochrome c reductase are inhibited also. the inhibitor constant for both reactions (ki) is 0.075 plus or minus 0.012 mm. nadh dehydrogenase is not inhibited significantly. 3. the inhibition of succinate:cytochrome c reductase is associated for chemotrophic membranes with ki equals 0.22 plus or minus 0.03 mm and for phototrophic membrane ...1975164937
spectroscopic properties of low-spin ferrous heme complexes and hemeproteins at 77degrees k. 1975164862
coupling factor atpase complex of rhodospirillum rubrum. purification and characterization of an oligomycin and n,n'-dicyclohexylcarbodiimide-sensitive (ca+ + mg2+) atpase complex sensitive to the energy transfer inhibitors oligomycin, dicyclohexylcarbodiimide and venturicidin has been solubilized from rhodospirillum rubrum chromatophores with triton x-100 and further purified by centrifugation on a glycerol gradient. the partially purified rrfo . f1 contains 13 distinct polypeptide subunits, as revealed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, including the subunits of the oligomycin-sensitive, water-soluble rrf1 atpase. the atpase ...1979158383
purification of the energy-transducing adenosine triphosphatase complex from rhodospirillum rubrum.the oligomycin- and n,n'-dicyclohexylcarbodiimide-sensitive adenosine triphosphatase complex extracted with triton x-100 from the chromatophores of rhodospirillum rubrum was extensively purified. the purification procedure included (diethylamino)ethylcellulose chromatography and glycerol gradient centrifugation. the specific activity of mg2+-dependent atp hydrolysis in the purified preparation increased about 11-fold, while that of ca2+-dependent atp hydrolysis increased 50-fold as compared with ...1979157774
properties of the f0f1 atpase complex from rhodospirillum rubrum chromatophores, solubilized by triton x-100.1. a cold-stable oligomycin-sensitive f0f1 atpase complex from chromatophores of rhodospirillum rubrum fr 1 was solubilized by triton x-100 and purified by gel filtration. 2. the f0f1 complex is resolved by sodium dodecyl sulfate electrophoresis into 14 polypeptides with approximate molecular weights in the range of 58000--6800; five of these polypeptides are derived from the f1 moiety of the complex which carries the catalytic centers of the enzyme. 3. the purified f0f1 complex is homogeneous a ...1979157277
preparation of the soluble atpase from mitochondria, chloroplasts, and bacteria by the chloroform technique. 1979156841
purification, subunit structure, and kinetics of the chloroform-released f1atpase complex from rhodospirillum rubrum and its comparison with f1atpase forms isolated by other methods.a stable and homogeneous adenosine-5'-triphosphatase (atpase, ec has been solubilized from rhodospirillum rubrum (r. rubrum) chromatophores by chloroform extraction. purification of the ca2+-dependent atpase activity was 200-fold. ca2+ can be replaced by mg2+, cd2+, and mn2+. the km for ca-atp (0.17 mm) is increased about 5-fold during solubilization of the enzyme, whereas the km values for mg-atp (0.029 mm) and cd-atp (0.014 mm) are not affected. the chloroform-released atpase has a mo ...1979155949
bound nucleotides and phosphorylation in rhodospirillum rubrum. 1979155454
immunological and reconstitution studies on the adenosine triphosphatase complex from rhodospirillum rubrum.studies on restoration of membrane-bound adenosinetriphosphatase (atp phosphohydrolase, ec from rhodospirillum rubrum show that the delta-subunit is capable of binding to the f1 factor or to the f0 moiety of the f0-f1 atpase complex. this subunit is thus likely involved in linking the f0 and f1 factor. during solubilization of the oligomycin-sensitive f0-f1 atpase complex with triton x-100 the detergent becomes specifically associated with the lipophilic f0 part of the enzyme complex. c ...1979153155
the interactions of coupling atpases with nucleotides. 1978147104
inhibition of energy conservation reactions in chromatophores of rhodospirillum rubrum by antibiotics. 1978147053
coupling factor atpase complex of rhodospirillum rubrum. purification and properties of a reconstitutively active single subunit. 1977144735
inhibition of the proton-translocating adenosine triphosphatase from chromatophores of photosynthetic bacteria by free bivalent cations and adenosine triphosphate [proceedings]. 1977144630
[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
coupling factor adenosine triphosphatase-complex of rhodospirillum rubrum. isolation of an oligomycin-sensitive ca2+, mg2+--atpase. 1977142656
coupling factors atpases from photosynthetic bacteria. 1976134033
effect of aurovertin on energy transfer reactions in rhodospirillum rubrum chromatophores. 1975131702
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
immunological and fluorescence studies with the coupling factor atpase from rhodospirillum rubrum.1. purification of the coupling factor atpase from rhodospirillum rubrum has been achieved by a combination of a previously described procedure with chromatography on deae-sephadex a50. 2. identification of the coupling factor atpase during purification, and estimation of the relative amount of the enzyme in each fraction was greatly simplified by utilization of its unusual fluorescence. 3. preparations of r. rubrum coupling factor atpase injected into rabbits yielded antisera which were suitabl ...1975126080
interaction of a coupling factor from rhodospirillum rubrum with coupling factor deficient chromatophores.a coupling factor necessary for the photophosphorylation and mg2+-atpase activities in rhodospirillum rubrum chromatophores has been separated from these particles. although the redox potential of coupling factor deficient chromatophores is slightly more oxidized than of the control, the addition of the coupling factor for reconstitution does not alter the redox potential. phenazine methosulfate cannot restore or significantly enhance the photophosphorylation activities of uncoupled or reconstit ...1975125569
on the subunit composition of the coupling factor (atpase) from rhodospirillum rubrum. 1975124669
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
removal of an adenine-like molecule during activation of dinitrogenase reductase from rhodospirillum rubrum.during the activation of the inactive dinitrogenase reductase from rhodospirillum rubrum, an adenine-like molecules is lost and phosphate is found on both active and inactive forms of the protein. atp and divalent metals are required for activation of the reduced protein, but atp is not required for activation of phenazine methosulfate-oxidized dinitrogenase reductase. snake venom diesterase and spleen diesterase have no effect on the inactive protein; alkaline phosphatase removes phosphate from ...1979118462
disintegration of rhodospirillum rubrum chromatophore membrane into photoreaction units, reaction centers, and ubiquinone-10 protein with mixture of cholate and deoxycholate.1. the membrane of rhodospirillum rubrum chromatophores was disintegrated with mild detergents (cholate and deoxycholate) in order to study the spatial arrangement of the functional proteins in the photochemical apparatus and the electron transport system in the membrane. 2. the components solubilized from the membrane by a mixture of cholate and deoxycholate (c-doc) were separated into four fractions by molecular-sieve chromatography in the presence of c-doc; they were designated as f1, f2, f3, ...1979118165
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
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
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
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
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
lipopolysaccharides of photosynthetic prokaryotes. 1979115382
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
a quantitative assay for bacterial rna polymerases. 1979114520
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
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
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
[functional organization of the electron transport chain of rhodospirillum rubrum chromatophores in the absence of an exogenous electron donor]. 1979113038
[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
[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
[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
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
[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
membrane potential and reconstitution. 1979110998
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
[noncyclic electron transport and membrane potential generation in the chromatophores of rhodospirillum rubrum]. 1979110361
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
modification of ribulose bisphosphate carboxylase from rhodospirillum rubrum with tetranitromethane. 1979110331
[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
[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
activation of ala synthetase by reduced thioredoxin in rhodopseudomonas spheroides y. 1979109312
characterisation of reaction centers and their phospholipids from rhodospirillum rubrum.1. reaction centers from rhodospirillum rubrum have been extracted with the zwitterionic detergent lauryl dimethyl amine oxide. subsequent purification has been achieved by gel filtration and ion-exchange chromatography. the pure reaction centers are composed of three protein subunits (l, m, h), bacteriocholorophyll and bacteriopheophytin in the ratio 2 : 1 and phospholipids. 2. the phospholipid composition has been found to be similar to that of whole chromatophore membrane, except that diphosp ...1979109118
photooxidase activity of rhodospirillum rubrum chromatophores and reaction center complexes. the role of non-cyclic electron transfer in generation of the membrane potential. 1979109117
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
ribulose bisphosphate carboxylases from chromatium vinosum and rhodospirillum rubrum and their role in photosynthetic carbon assimilation. 1978106836
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
ribulose 1,5-bisphosphate carboxylase from autotrophic micro-organisms [proceedings]. 1978105954
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
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
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
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
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
energy-liked reactions in photosynthetic bacteria. x. solubilization of the membrane-bound energy-linked inorganic pyrophosphatase of rhodospirillum rubrum. 1978102323
resolution and reconstitution of rhodospirillum rubrum pyridine dinucleotide transhydrogenase: localization of substrate binding sites. 1978102261
involvement of an essential arginyl residue in the coupling activity of rhodospirillum rubrum chromatophores. 1978102254
preparation of nitrogenase. 1978101737
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
[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
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
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
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
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
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
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
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