| inactivation of citrate lyase from rhodopseudomonas gelatinosa by a specific deacetylase and inhibition of this inactivation by l-(+1-glutamate. | a previously unrecognized enzyme, citrate lyase deacetylase, has been purified about 140-fold from cell extracts of rhodopseudomonas gelatinosa. it catalyzed the conversion of enzymatically active acetyl-s-citrate lyase into the inactive hs-form and acetate. the enzyme exhibited an optimal rate of inactivation at ph 8.1. because of the instability of acetyl-s-citrate lyase at acidic and alkaline ph values, all assays were carried out at ph 7.2, where the spontaneous hydrolysis of the acetyl-s-ci ... | 1975 | 356 |
| sn-glycerol-3-phosphate acyltransferase activity in particulate preparations from anaerobic, light-grown cells of rhodopseudomonas spheroides. involvement of acyl thiolester derivatives of acyl carrier protein in the synthesis of complex lipids. | crude particulate preparations obtained from anaerobic, light-grown cells of rhodopseudomonas spheroides have been shown to possess a significant level of sn-glycerol-3-phosphate acyltransferase (ec 2.3.1.15) activity. in contrast to the enzyme from escherichia coli, the r. spheroides glycerophosphate acyltransferase has a high specificity for acyl thiolester derivatives of acyl carrier protein (acp) as acyl donors for the reaction. only limited , nonlinear glycerophosphate incorporation into li ... | 1975 | 387 |
| photoinduced reduction of nad(p) in the cells of green sulfur bacteria. | the spectrum of a photoinduced increase in luminescence of the cells of the gree sulphur bacterium chlorobium limicola f. thiosulfatophilum, within the range of 400 to 520 nm, was found to correspond to the spectrum of luminescence of nadh in the protein-bound form. photoinduced reduction of nad(p) in green bacteria, contrary to purple bacteria, is not susceptible to the action of p-chlorocarbonylcyanide phenlhydrazone which uncouples photophosphorylation. therefore, in chlorobium limicola f. th ... | 1975 | 2843 |
| properties of the flash-induced proton binding encountered in membranes of rhodopseudomonas sphaeroides: a functional pk on the ubisemiquinone? | | 1976 | 4014 |
| ubiquinone-cytochrome b electron and proton transfer: a functional pk on cytochrome b50 in rhodopseudomonas sphaeroides membranes. | | 1976 | 4015 |
| control of 5-aminolaevulinate synthetase activity in rhodopseudomonas spheroides. | rhodopseudomonas spheroides can grow in a defined medium with either light or oxygen as an energy source. cells grown anaerobically or at very low oxygen tensions are rich in the photosynthetic pigment bacteriochlorophyll, whereas this pigment is virtually absent in cells grown under high oxygen tensions. aminolaevulinate synthetase, the first enzyme on the pathway to bacteriochlorophyll, appears to play an important role in the control of bacteriochlorophyll synthesis. thus, the enzyme has a hi ... | 1976 | 4844 |
| ph dependence of the oxidation-reduction potential of cytochrome c2. | the ph dependence of the spectra and of the oxidation-reduction potential of three cytochromes c2, from rhodopseudomonas capsulata, rhodopseudomonas sphaeroides and rhodomicrobium vannielii, were studied. a single alkaline pk was observed for the spectral changes in all three ferricytochromes. in rps. capsulata cytochrome c2 this spectroscopic pk corresponds to the pk observed in the dependence of oxidation-reduction potential on ph. for the other two cytochromes the oxidation-reduction potentia ... | 1976 | 6058 |
| isolation and partial characterization of the cytochrome oxidase from rhodopseudomonas palustris. | the cytochrome oxidase (ec 1.9.3.1) of rhodopseudomonas palustris was extracted with triton x-100 plus kcl, from the membrane fraction of cells grown aerobically in the dark. the solubilized enzyme was purified by (nh4)2so4 precipitation and chromatography on deae-cellulose. the purification resulted in a 108-fold enrichment of cytochrome oxidase on the basis of specific activity when compared to the membrane fraction. the purified enzyme was phosphate-sensitive (less than mm), oxidized reduced ... | 1976 | 9286 |
| inorganic nitrogen assimilation by the photosynthetic bacterium rhodopseudomonas capsulata. | the photosynthetic bacterium rhodopseudomonas capsulata lacks glutamate dehydrogenase and normally uses the glutamine synthetase/glutamate synthase sequence of reactions for assimilation of n2 and ammonia. the glutamine synthetase in cell-free extracts of the organism is completely sedimented by centrifugation at 140,000 x g for 2 h, is inhibited by l-alanine but not by adenosine 5'-monophosphate, and exhibits two apparent km values for ammonia (ca. 13 mum and 1 mm). | 1976 | 10281 |
| 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. ... | 1976 | 12621 |
| studies on glycosidases acting on glycoconjugates (author's transl). | | 1976 | 13130 |
| different molecular forms of d-ribulose-1,5-bisphosphate carboxylase from rhodopseudomonas sphaeroides. | ribulose-1,5-bisphosphate (rbu-p2) carboxylase isolated from rhodopseudomonas sphaeroides 2.4.1.ga was separated into two different forms by deae-cellulose column chromatography. both forms, designated peak i and peak ii have been purified to homogeneity by the criterion of polyacrylamide disc-gel electrophoresis. the peak i carboxylase has a molecular weight of 550,000, while the peak ii carboxylase is a smaller protein having a molecular weight of approximately 360,000. sodium dodecyl sulfate ... | 1977 | 14141 |
| the ph dependence of the oxidation-reduction midpoint potential of cytochromes c2 in vivo. | a recent report by pettigrew et al. biochim, biophys. acta 430, (1976), 197-208 has examined the ph dependence of the oxidation-reduction midpoint potential of cytochromes c2 in vitro. in media of low ionic strength, these workers identified several pks on the oxidized forms of the cytochromes, and in some cases there were also pks on the reduced species. in this work we examine the ph dependence of the midpoint potentials of the cytochromes in situ, attached to the chromatophore membrane. under ... | 1977 | 14684 |
| bacterial photosynthetic phosphorylation under conditions of limited electron flow. | | 1977 | 20372 |
| adenylylation/deadenylylation control of the glutamine synthetase of rhodopseudomonas capsulata. | | 1977 | 23287 |
| a pleiotropic mutant of rhodopseudomonas capsulata defective in nitrogen metabolism. | wild type strains of rhodopseudomonas capsulata typically can use n2, nh+4, or various nitrogenous organic compounds as n sources for photosynthetic growth. one class of mutants selected for inability to grow on n2 (nif-) also shows simultaneous loss of capacity to obtain n from numerous organic substrates. when supplied at relatively high concentrations, ammonia can be used as the sole n source for growth of such strains. enzymatic analysis of one mutant (w11) indicates that the pleiotropic eff ... | 1977 | 23732 |
| the electrochemical proton gradient generated by light in membrane vesicles and chromatophores from rhodopseudomonas sphaeroides. | | 1978 | 25184 |
| 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 ... | 1978 | 26430 |
| equilibrium and disequilibrium in the ubiquinone-cytochrome b-c2 oxidoreductase or rhodopseudomonas sphaeroides. | | 1978 | 27385 |
| nitrogen assimilation in rhodopseudomonas acidophila. | rhodopseudomonas acidophila strain 7050 assimilated ammonia via a constitutive glutamine synthetase/glutamate synthase enzyme system. glutamine synthetase had a km for nh+4 of 0.38 mm whilst the nicotinamide adenine dinucleotide linked glutamate synthase had a km for glutamine of 0.55 mm. r. acidophila utilized only a limited range of amino acids as sole nitrogen sources: l-alanine, glutamine and asparagine. the bacterium did not grow on glutamate as sole nitrogen source and lacked glutamate deh ... | 1978 | 31145 |
| response of 9-aminoacridine fluorescence to transmembrane ph-gradients in chromatophores from rhodopseudomonas sphaeroides. | | 1978 | 33044 |
| derepression of nitrogenase activity in glutamine auxotrophs of rhodopseudomonas capsulata. | in contrast to wild-type cells, glutamine auxotrophs of the photosynthetic bacterium rhodopseudomonas capsulata synthesize nitrogenase, produce h2 (catalyzed by nitrogenase), and continue to reduce dinitrogen to ammonia in the presence of exogenous nh4+. the glutamine synthetase activity of such mutants is less than 2% of that observed in the wild type. it appears that glutamine synthetase plays a significant role in regulation of nitrogenase synthesis in r. capsulata. | 1979 | 35518 |
| factors controlling the binding of two protons per electron transferred through the ubiquinone and cytochrome b/c2 segment of rhodopseudomonas sphaeroides chromatophores. | 1. on every turnover, 2.0 protons can be bound by the membrane for each single electron moving through the q-b/c2 oxidoreductase. 2. one proton (h+ii) binding reaction is, and one (h+i) is not, sensitive to antimycin. 3. the redox states of electron transfer components other than the proton binding agents can affect both the rate of proton uptake and the apparent pk values on the agents binding the protons. 4. the presence of valinomycin under certain well-defined conditions can strongly influen ... | 1979 | 36140 |
| from extracellular to intracellular: the establishment of mitochondria and chloroplasts. | paracoccus and rhodopseudomonas are unusual among bacteria in having a majority of the biochemical features of mitochondria; blue-green algae have many of the features of chloroplasts. the theory of serial endosymbiosis proposes that a primitive eukaryote successively took up bacteria and blue-green algae to yield mitochondria and chloroplasts respectively. possible characteristics of transitional forms are indicated both by the primitive amoeba, pelomyxa, which lacks mitochondria but contains a ... | 1979 | 36620 |
| spectroscopic and kinetic properties of the transient intermediate acceptor in reaction centers of rhodopseudomonas sphaeroides. | the photoreductive trapping of the transient, intermediate acceptor, i-, in purified reaction centers of rhodopseudomonas sphaeroides r-26 was investigated for different external conditions. the optical spectrum of i- was found to be similar to that reported for other systems by shuvalov and klimov ((1976) biochim. biophys. acta 400, 587--599) and tiede et al. (p.m. tiede, r.c. prince, g.h. reed and p.l. dutton (1976) febs lett. 65, 301--304). the optical changes of i- showed characteristics of ... | 1979 | 36906 |
| light-induced, carrier-mediated transport of tetracycline by rhodopseudomonas sphaeroides. | tetracycline accumulation by the phototrophic bacterium rhodopseudomonas sphaeroides has been studied, using the fluorescence properties of the antibiotic and measuring uptake of [7- 3h]tetracycline. accumulation was carrier mediated, with a km of approximately 300 micronm. efflux also appeared to be carried mediated, with a km of 25 mm. chlorotetracycline competitively inhibited tetracycline transport. the transport was energy dependent. efflux occurred during the influx process, and an energy- ... | 1979 | 37230 |
| effect of surface potential on the intramembrane electrical field measured with carotenoid spectral shift in chromatophores from rhodopseudomonas sphaeroides. | changes in the surface potential, the electrical potential difference between the membrane surface and the bulk aqueous phase were measured with the carotenoid spectral shift which indicates the change of electrical field in the membrane. chromatophores were prepared from a non-sulfur purple bacterium, rhodopseudomonas sphaeroides, in a low-salt buffer. surface potential was changed by addition of salt or by ph jump as predicted by the gouy-chapman diffuse double layer theory. when a salf was ad ... | 1979 | 37904 |
| electron and proton transport in the ubiquinone cytochrome b-c2 oxidoreductase of rhodopseudomonas sphaeroides. patterns of binding and inhibition by antimycin. | the effect of antimycin on the ubiquinone cytochrome b-c2 (q b-c2) oxidoreductase of the photosynthetic bacterium rhodopseudomonas sphaeroides has been studied under controlled oxidation-reduction potential (eh) conditions by equilibrium measurements and by rapid kinetic analysis of single turnover flash.induced electron and proton translocations. 1. antimycin shifts the alpha-band of ferro b50 (lambda max 560 nm) by 1 to 2 nm toward the red but has no apparent effect on the equilibrium oxidatio ... | 1979 | 38253 |
| equilibrium and kinetic measurements of the redox potentials of cytochromes c2 in vitro and in vivo. | the equilibrium oxidation-reduction mipoint potential (em) of isolated rhodopseudomonas sphaeroides cytochrome c2 exhibits a ph-dependent behavior which can be ascribed to a pk on the oxidized form at ph 8.0 (pettigrew et al. (1975) biochim. biophys. acta 430, 197-208). however, as with mammalian cytochrome c (brandt, k.g. parks, p.c., czerlinski, g.h. and hess, g.p. (1966) j. biol. chem. 241, 4180-4185) this pk can more properly be attributed to the combination of a pk beyond ph 11, and a slow ... | 1979 | 39597 |
| the purification of glutamine synthetase from azotobacter and other procaryotes by blue sepharose chromatography. | we report the facile purification of glutamine synthetase (l-glutamate: ammonia ligase (adenosine 5'-diphosphate-forming), ec 6.3.1.2) in both the adenylylated and unadenylylated form, from azotobacter vinelandii atcc 12837. a general affinity column, which used as an affinity ligand reactive blue 2 dye (cibacron blue) covalently linked to agarose, was employed as an efficient first step of purification. further purification to electrophoretic homogeneity employed deae-cellulose chromatography a ... | 1979 | 39606 |
| electron acceptors of bacterial photosynthetic reaction centers. ii. h+ binding coupled to secondary electron transfer in the quinone acceptor complex. | the photoreduction of ubiquinone in the electron acceptor complex (qiqii) of photosynthetic reaction centers from rhodopseudomonas sphaeroides, r26, was studied in a series of short, saturating flashes. the specific involvement of h+ in the reduction was revealed by the ph dependence of the electron transfer events and by net h+ binding during the formation of ubiquinol, which requires two turnovers of the photochemical act. on the first flash qii receives an electron via qi to form a stable ubi ... | 1979 | 41574 |
| 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 ... | 1979 | 42641 |
| characterization of antiserum directed against form ii ribulose 1,5-bisphosphate carboxylase from rhodopseudomonas sphaeroides. | antiserum directed against form ii ribulose 1,5-bisphosphate carboxylase from rhodopseudomonas sphaeroides showed no cross-reactivity towards the form i enzyme as evidenced by a lack of immunopreciptation. in addition, this antiserum failed to inhibit form i enzymatic activity. | 1977 | 70425 |
| 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 ... | 1977 | 95659 |
| 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 ... | 1978 | 96854 |
| 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 ... | 1978 | 96856 |
| 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 ... | 1978 | 96875 |
| 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. | 1978 | 97281 |
| 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 ... | 1978 | 99169 |
| 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 ... | 1978 | 99172 |
| activation of ala synthetase by reduced thioredoxin in rhodopseudomonas spheroides y. | | 1979 | 109312 |
| 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 ... | 1978 | 110568 |
| [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 ... | 1979 | 112359 |
| 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 ... | 1979 | 114213 |
| lipopolysaccharides of photosynthetic prokaryotes. | | 1979 | 115382 |
| 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 ... | 1979 | 115463 |
| 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 ... | 1979 | 116681 |
| [enzymes of carbohydrate metabolism in phototrophic bacteria]. | purple sulphur bacteria (chromatium minutissimum, ectothiorhodospira shaposhnikovii, thiocapsa roseopersicina), non-sulphur bacteria (rhodopseudomonas palustris rh. viridis), and green sulphur bacteria (chlorobium limicola f. thiosulfatophillum) contain all enzymes of the fructose diphosphate pathway of carbohydrate transformation, and also glucose-6-phosphate dehydrogenase. the activity of fructose diphosphate aldolase, triose phosphate dehydrogenase, and glucose-6-phosphate dehydrogenase incre ... | 1975 | 125844 |
| coupling factors atpases from photosynthetic bacteria. | | 1976 | 134033 |
| different degradation pathways for glucose and fructose in rhodopseudomonas capsulata. | in rhodopseudomonas capsulata the enzymes of the entner-doudoroff pathway and the embden-meyerhof pathway have been examined. fructose-grown cells contained inducible activities of phosphoenolpyruvate-fructosephospho-transferase and 1-phosphofructokinase and only low levels of fructokinase and 6-phosphofructokinase. although fructose-grown cells contained, in addition, all the enzymes of the entner-doudoroff pathway together with fructose-1,6-diphosphatase and phosphoglucose isomerase, the entne ... | 1977 | 139134 |
| regulation of glucose, fructose and sucrose catabolism in rhodopseudomonas capsulata. | regulation of glucose, fructose and sucrose catabolism was studied in rhodopseudomonas capsulata grown under phototrophic conditions. the sequence of preference for the utilization of the sugar substrates was fructose, glucose, sucrose. the presence of a preferred substrate did not completely suppress the utilization of the less preferred. glucose-6-phosphate dehydrogenase, the key enzyme of glucose and sucrose catabolism, exhibited sigmoidal substrate saturation curves and was inhibited by phos ... | 1978 | 147929 |
| nucleotide translocation across the cytoplasmic membrane in the photosynthetic bacterium rhodopseudomonas capsulata. | | 1978 | 149026 |
| physical parameters and possible regulation of zeta-aminolevulinic acid synthetase. | physical measurements were made on the zeta-aminolevulinic acid synthetase from rhodopseudomonas spheroides. these include a stokes radius of 3.8 nm, determined by gel filtration, and sedimentation coefficient of 5.46 s by sucrose density gradient centrifugation. from these measurements and the value of partial specific volume of 0.732 ml/g determined from the amino acid composition, the following physical constants were calculated: molecular weight, 88000; diffusion coefficient, 5.65 x 10(-7) c ... | 1978 | 153666 |
| lysine as the substrate binding site of porphobilinogen synthase of rhodopseudomonas spheroides. | the 14c labelled inactive protein obtained by sodium borohydride reduction of the enzyme, porphobilinogen synthase of rhodopseudomonas spheroides, in the presence of [4-14c]5-aminolevulinic acid, gave on acid hydrolysis and subsequent electrophoresis or two-dimensional chromatography a major radioactive spot which was confirmed to be n-epsilon-[4-(-5aminovaleric acid)]lysine (ala-lysine) by comparing its co-chromatographic and electrophoretic behaviour with the chemically synthesized ala-lysine. ... | 1978 | 153667 |
| mode of binding of pyridoxal phosphate to 5-aminolevulinate synthase. | 5-aminolevulinate synthase of rhodopseudomonas spheroides interacts with its cofactor, pyridoxal phosphate, and shows an absorption maximum at 430 nm with a probable shoulder at 320--330 nm. the enzyme-plp complex absorbing at 430 nm is the predominant species at ph 7.2 and can be reduced by nabh4 at neutral ph with a spectral shift of the absorption maximum to 325 nm. these data suggests the formation of a schiff base rather than a substituted aldimine between the enzyme and pyridoxal phosphate ... | 1978 | 154217 |
| preparation of the soluble atpase from mitochondria, chloroplasts, and bacteria by the chloroform technique. | | 1979 | 156841 |
| orientation of chromatophores and spheroplast-derived membrane vesicles of rhodopseudomonas sphaeroides: analysis by localization of enzyme activities. | | 1979 | 157720 |
| correlation between atp synthesis and the decay of the arotenoid band shift after single flash activation of chromatophores from rhodopseudomonas capsulata. | atp synthesis and the acceleration of the decay of the carotenoid absorption band shift after single flash excitation of rhodopseudomonas capsulata chromatophores were compared. the two processes behave similarly with respect to: (1) adp and pi concentration; (2) inhibition by efrapeptin and venturicidin, and (3) inhibition by valinomycin/k+ and by ionophores. taken together with earlier evidence for the electrochromic nature of the carotenoid band shift the data support the contention that posi ... | 1979 | 158382 |
| immunochemical analysis of membrane vesicles and chromatophoresis of rhodopseudomonas sphaeroides by crossed immunoelectrophoresis. | | 1979 | 159833 |
| distribution of thioredoxins in cyanobacteria. | the presence of thioredoxin was demonstrated in 20 strains of cyanobacteria as well as in one phototrophic bacterium rhodopseudomonas sulfidophila and in thiobacillus denitrificans. thioredoxin activity was not found in cyanophora paradoxa and in porphyridium cruentum using the thioredoxin-dependent paps-sulfotransferase activity from synechococcus 6301 as assay system. | 1979 | 161845 |
| the stimulation of photophosphorylation and atpase by artificial redox mediators in chromatophores of rhodopseudomonas capsulata at different redox potentials. | (1) inhibition of cyclic phosphorylation in chromatophores of rhodopseudomonas capsulata by antimycin a can be fully reversed by artificial redox mediators, provided the ambient redox potential is maintained around 200 mv. the redox mediator need not be a hydrogen carrier in its reduced form, n-methyl-phenazonium methosulfate and n,n,n',n'-tetramethyl-p-phenylenediamine being equally effective. however, the mediator needs to be lipophilic. endogenous cyclic phosphorylation is fastest around 130 ... | 1979 | 162342 |
| asymmetry of an energy transducing membrane the location of cytochrome c2 in rhodopseudomonas spheroides and rhodopseudomonas capsulata. | monospecific antibodies have been prepared against cytochrome c2 from rhodopseudomonas spheroides and rhodopseudomonas capsulata, and against cytochrome c' from rps. capsulata. these antibodies precipitated their respective antigens, but did not cross react with a wide range of procaryotic or eucaryotic cytochromes, or with other bacterial proteins. the cytochromes produced during aerobic growth were immunologically indistinguishable from those produced during photosynthetic growth. cytochrom ... | 1975 | 164941 |
| a kinetic completion of the cyclic photosynthetic electron pathway of rhodopseudomonas sphaeroides: cytochrome b-cytochrome c2 oxidation-reduction. | in rhodopseudomonas sphaeroides, following a single-turnover flash of light, cytochrome c2 is oxidized by reaction center bacteriochlorophyll, and a cytochrome b is reduced by the primary electron acceptor, probably via ubiquinone. in this report we show that, in the uncoupled state, the rate of re-oxidation of the cytochrome b is identical to the rate of reduction of the cytochrome c2, a kinetic completion of the cyclic photosynthetic electron transport system. | 1975 | 166671 |
| some experiments on the primary electron acceptor in reaction centres from rhodopseudomonas sphaeroides. | the bacterial reaction center absorbance change at 450 nm (a-450) assigned to an anionic semiquinone, has been suggested as a candidate for the reduced form of the primary electron acceptor in bacterial photosynthesis. in reaction centers of rhodopseudomonas sphaeroides we have found kinetic discrepancies between the decay of a-450 and the recovery of photochemical competence. in addition, no proton uptake is measurable on the first turnover, although subsequent ones elicit one proton bound per ... | 1975 | 168920 |
| [composition and content of cytochromes in rhodopseudomonas palustris in relation to growth conditions]. | differential spectra, co spectra and spectra of hemochromes were studied in the cells of rhodopseudomonas palustris grown in aerobic conditions in the light and in the darkness; the terminal oxidase was cytochrome a. this cytochrome was not detected in the cells cultivated in anaerobic conditions in the light. the content of cytochromes b was higher in the cells grown in aerobic conditions in the darkness; the content of cytochromes c was higher in the cells cultivated in anaerobic conditions in ... | 1975 | 169455 |
| characterization of two soluble ferredoxins as distinct from bound iron-sulfur proteins in the photosynthetic bacterium rhodospirillum rubrum. | in 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 ... | 1975 | 172494 |
| primary structure determination of two cytochromes c2: close similarity to functionally unrelated mitochondrial cytochrome c. | the amino-acid sequences of the cytochromes c2 from the photosynthetic non-sulfur purple bacteria rhodomicrobium vannielii and rhodopseudomonas viridis have been determined. only a single residue deletion (at position 11 in horse cytochrome c) is necessary to align the sequences with those of mitochondrial cytochromes c. the overall sequence similarity between these cytochromes c2 and mitochondrial cytochromes c is closer than that between mitochondrial cytochromes c and the other cytochromes c ... | 1976 | 174109 |
| photochemical activities of reaction centers from rhodopseudomonas sphaeroides at low temperature and in the presence of chaotropic agents. | light-induced absorbance changes were measured at low temperatures in reaction center preparations from rhodopseudomonas sphaeroides. absorbance difference spectra measured at 100 degrees k show that ubiquinone is photoreduced at this temperature, both by continuous light and by a short actinic flash. the reduction occurred with relatively high efficiency. these results give support to the idea that ubiquinone is involved in the primary photochemical reaction in rhodopseudomonas sphaeroides. red ... | 1976 | 174746 |
| 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 ... | 1976 | 183815 |
| 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 ... | 1976 | 183816 |
| isolation of a membrane-bound protein having coupling factor capacity as well as adp-pi exchange and adpase activities from rhodopseudomonas viridis. | | 1976 | 187453 |
| the effect of dibromothymoquinone on respiratory and photosynthetic electron transport in rhodopseudomonas capsulata chromatophores. | dibromothymoquinone has been shown to inhibit light-induced cytochrome b reduction, and oxidation of succinate and nadh by chromatophores of rhodopseudomonas capsulata. the half-inhibitory concentration of light-induced reactions and nadh oxidation is 2.5 mum, but of succinate oxidation is 16 mum. hexane extraction inhibited oxidation of nadh and succinate equally. the results are interpreted to suggest that ubiquinone is concerned in all three processes described, but that the pools associated ... | 1976 | 189722 |
| time-resolved esr and chemically induced dynamic electron polarisation of the primary reaction in a reaction center particle of rhodopseudomonas sphaeroides wild type at low temperature. | | 1977 | 190035 |
| reduction of iron and synthesis of protoheme by spirillum itersonii and other organisms. | membranes from spirillum itersonii reduce ferric iron to ferrous iron with reduced nicotinamide adenine dinucleotide or succinate as a source of reductant. iron reduction was measured spectrophotometrically at 562 nm using ferrozine, which chelates ferrous iron specifically. reduced nicotinamide adenine dinucleotide or succinate was also effective as a source of iron. the effects of respiratory inhibitors suggested that reduction of iron occurs at one or more sites on the respiratory chain befor ... | 1977 | 190208 |
| reconstitution of photosynthetic electron transport and photophosphorylation in cytochrome-c2-deficient membrane preparation of rhodopseudomonas capsulata. | | 1977 | 190950 |
| 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 ... | 1977 | 192272 |
| the influence of transmembrane potentials of the redox equilibrium between cytochrome c2 and the reaction center in rhodopseudomonas sphaeroides chromatophores. | | 1977 | 196931 |
| [evaluation and determination of the antibacterial properties of pesticide combinations]. | | 1977 | 196981 |
| synthesis of photopigments and electron transport components in synchronous phototrophic cultures of rhodopseudomonas sphaeroides. | the kinetics of synthesis and incorporation of the photosynthetic pigments and several of the major oxidative and photosynthetic electron transport components of rhodopseudomonas sphaeroides have been studied during synchronous and asynchronous phototrophic growth. the photosynthetic pigments and cytochromes c and b, measured spectroscopically, exhibited continuous patterns of synthesis and incorporation into the membrane particulate fraction in both synchronous and asynchronous cultures. succin ... | 1978 | 201634 |
| reduction kinetics of bacterial cytochromes c2. | | 1977 | 202201 |
| single and multiple turnover reactions in the ubiquinone-cytochrome b-c2 oxidoreductase of rhodopseudomonas sphaeroids: the physical chemistry of the major electron donor to cytochrome c2, and its coupled reactions. | we have examined the thermodynamic properties of the physiological electron donor to ferricytochrome c2 in chromatophores from the photosynthetic bacterium rhodopseudomonas sphaeroides. this donor (z), which is capable of reducing the ferricytochrome with a halftime of 1-2 ms under optimal conditions, has an oxidation-reduction midpoint potential of close to 150 mv at ph 7.0, and apparently requires two electrons and two protons for its equilibrium reduction. the state of reduction of z, which m ... | 1977 | 202311 |
| determination of the decay rates of the triplet state of rhodopseudomonas sphaeroides by fast laser-flash esr spectroscopy. | | 1978 | 202494 |
| characterization of a soluble nadh-independent nitrate reductase from the photosynthetic bacterium rhodopseudomonas capsulata. | the assimilatory nitrate reductase was purified 60-fold from a newly isolated, nitrate assmilating strain of the photosynthetic bacterium rhodopseudomonas capsulata. the enzyme had a molecular weight of about 180 000 dalton and was typically prokaryotic in that it was not active with reduced pyridine nucleotides but rather with reduced flavins. | 1977 | 203130 |
| cytochrome c2--an electron carrier shared by the respiratory and photosynthetic electron transport chain of rhodopseudomonas capsulata. | | 1978 | 203482 |
| mutational analysis of serine-glycine biosynthesis in rhodopseudomonas capsulata. | rhodopseudomonas capsulata possesses the enzymes of both the "phosphorylated" and the "non-phosphorylated" pathways of serine biosynthesis. certain mutants with lesions in the phosphorylated pathway are serine-glycine auxotrophs, though they still produce enzymes of the non-phosphorylated sequence. these results indicate that the phosphorylated pathway is essential for the synthesis of serine and glycine in r. capsulata under the condtions tested. | 1977 | 192715 |
| isolation and purification of reaction center from rhodopseudomonas viridis nhtc 133 by means of ldao. | two different procedures are described to isolate and purify the reaction center complex from rhodopseudomonas viridis nhtc 133 by means of the non-ionic detergent dodecyldimethylamine oxide. both reaction center particles thus obtained were active, as shown by a photobleaching centered at 975 nm. the reaction center also contained, in addition to bacteriochlorophyll, bacteriopheophytin. other components were also found in this particle: cytochromes c553 and c558 and a menaquinone-like substance ... | 1976 | 185975 |
| [comparative study of b890 pigment-lipoprotein complexes from sulfur (chromatium minutissimum) and non-sulfur (rhodopseudomonas palustris) purple photosynthesizing bacteria]. | pigment-lipoprotein b890 complexes containing reaction center and "light-focusing" bacteriochlorophyll a were isolated from photosynthetic membranes of sulfur (chromatium minutissimum) and non-sulfur (rhodopseudomonas palustris) purple bacteria after the treatment with triton x-100. the molecular weights of complexes were evaluated using several methods (200 000-300 000). by means of electron microscopy the sizes of complexes were found to be about 80 a. on the air-water interface hexagonal pack ... | 1978 | 207362 |
| [effect of growth conditions on the activity of the enzymes of cyclic 3':5'-amp synthesis and decay in phototrophic bacteria]. | activity, ratio and summary content of cyclic amp enzymes, adenylate cyclase and phosphodiesterase varied depending on growth conditions of phototrophic bacteria (rhodospirillum rubrum and rhodopseudomonas palustris). it suggests, that membrane-bound and soluble enzymes carry different functions. the increase of adenylate cyclase under chaning growth conditions was usually accompanied by the increase of phosphodiesterase. sharp increase of both enzymes activity was observed when bacteria were gr ... | 1978 | 207363 |
| second order kinetics of the reduction of cytochrome c2 by the ubiquinone cytochrome b-c2 oxidoreductase of rhodopseudomonas sphaeroides. | | 1978 | 207691 |
| properties of a cytochrome c-enriched light particulate fraction isolated from the photosynthetic bacterium rhodopseudomonas spheroides. | differential centrifugation of suspensions of french-press-disrupted rhodopseudomonas spheroides yielded a light particulate fraction that was different in many properties from the bulk membrane fraction. it was enriched in cytochrome c and had a low cytochrome b content. when prepared from photosynthetically grown cells this fraction had a very low specific bacteriochlorophyll content. the cytochrome c of the light particles differed in absorption maxima at 77k from cytochrome c2 attached to me ... | 1978 | 212023 |
| lipid-protein associations in chromatophores from the photosynthetic bacterium rhodopseudomonas sphaeroides. | lipid-protein interactions were examined in chromatophores isolated from the photosynthetic bacterium rhodopseudomonas sphaeroides using lipid spin-labels. the chromatophores contain fluid bilayer and a significant amount of lipid immobilized by membrane proteins. for a typical preparation of cells grown under 600 ft-c illumination, 59% of the spin-labeled fatty acids were bound. essentially the entire length of the 18-carbon fatty acid chain was immobilized, judging from results obtained with t ... | 1978 | 212104 |
| [picosecond fluorometry of rhodopseudomonas sphaeroides strain 1760-1 bacteria]. | | 1978 | 212114 |
| isolation and characterization of a membrane-bound, low-potential c-type cytochrome from purple photosynthetic bacteria, with special reference to rhodospirillum rubrum. | other investigators have isolated soluble, low-potential, c-type cytochromes (cytochrome c3) from a few photosynthetic procaryotes, i.e., a cyanobacterium and two species of purple nonsulfur bacteria. however, such cytochromes appeared to be absent from other purple bacteria, including rhodospirillum rubrum and chromatium vinosum. we now report evidence for the presence of low-potential c-type cytochromes in these two species, in which they were found to be bound to the photosynthetic membranes. ... | 1978 | 214418 |
| diffusion-potential-induced oxidation and reduction of cytochromes in chromatophores from rhodopseudomonas sphaeroides. | a membrane potential jump was induced by the addition of valinomycin in the presence of a kcl concentration gradient across the membrane of rhodopseudomonas sphaeroides chromatophores. as well as a carotenoid band shift, which is known to be an indicator of membrane potential, absorbance changes due to the oxidation-reduction reactions of cytochromes accompanied the jump. under aerobic conditions with no reductant added, a part of cytochrome c2 was reduced by an inside-positive potential jump of ... | 1978 | 214426 |
| evidence for antiferromagnetic exchange coupling in the tetranuclear high potential iron-sulfur protein of rhodopseudomonas gelatinosa. | | 1978 | 215143 |
| electrogenic events in the ubiquinone-cytochrome b/c2 oxidoreductase of rhodopseudomonas sphaeroides. | the reductant of ferricytochrome c2 in rhodopseudomonas sphaeroides is a component, z, which has an equilibrium oxidation-reduction reaction involving two electrons and two protons with a midpoint potential of 155 mv at ph 7. under energy coupled conditions, the reduction of ferricytochrome c2 by zh2 is obligatorily coupled to an apparently electrogenic reaction which is monitored by a red shift of the endogeneous carotenoids. both ferricytochrome c2 reduction and the associated carotenoid bands ... | 1979 | 216398 |
| the kinetics of flash-induced electron flow in bacteriochlorophyll-less membranes of rhodopseudomonas sphaeroides reconstituted with reaction centres. | | 1979 | 216400 |
| [oxidative phosphorylation capacity of rhodopseudomonas palustris during growth in light and darkness]. | assimilation of oxygen by the cells of rhodopseudomonas palustris grown in the light and in the darkness is stimulated by p-chlorocarbonylcyanidephanylhydrazone, suggesting respiration coupled to phosphorylatin. membranes of the cells grown in the light are capable of oxidative phosphorylation in the course of electron transport from nadh and succinate to o2 with p/o being 0.03 and 0.20, respectively. membranes of the cells grown in the darkness in aerobic conditions are capable of oxidative pho ... | 1976 | 180383 |
| [comparative study of lipid a of the pertussis microbe o-antigens differing in their toxicity. ii. infrared spectroscopy study of the structure of preparations of b. pertussis lipid a]. | | 1978 | 217208 |
| azethoxyl nitroxide spin labels. esr studies involving thiourea crystals, model membrane systems and chromatophores, and chemical reduction with ascorbate and dithiothreitol. | trans- and cis-azethoxyl nitroxides 1, 2, 3 and 4 can be trapped in the cavities of thiourea crystals. the presence of a single gauche conformation on either side of the pyrrolidine ring within the crystals was indicated by the esr spectra. rotation about the long molecular axis then corresponds approximately to y-axis motion of the nitroxide moiety. proxyl nitroxides in which the nitroxide group is located on the penultimate carbon of long chain lipids can also be trapped and were shown to adop ... | 1979 | 217428 |