TitleAbstractYear(sorted ascending)
preparation of the soluble atpase from mitochondria, chloroplasts, and bacteria by the chloroform technique. 1979156841
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
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
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
modification of ribulose bisphosphate carboxylase from rhodospirillum rubrum with tetranitromethane. 1979110331
hydrophobic membrane protein from chromatophores of rhodospirillum rubrum. structural and spectroscopic studies of monolayers and multilayers.a hydrophobic, lipid- and pigment-free polypeptide from the chromatophore membrane of rhodospirillum rubrum was spread from chloroform/methanol, pyridine and formic acid solutions at an air-water interface. surface pressure versus area isotherms of the monolayers formed at the interface were partially dependent upon the spreading solvent used. from the surface area at 20 dynes/cm compression, an average molecular area of 12.9 nm2/molecule was calculated for a polypeptide monolayer spread from ch ...1979110346
[noncyclic electron transport and membrane potential generation in the chromatophores of rhodospirillum rubrum]. 1979110361
comparative solvent perturbation of horse heart cytochrome c and rhodospirillum rubrum cytochrome c2.the extent of exposure of heme to solvent in horse heart cytochrome c and rhodospirillum rubrum c2 was investigated to determine whether a correlation exists between the properties of these oxidation-reduction proteins and their heme environments. solvent perturbation absorption difference spectra were measured using ethylene glycol, glycerol, and sucrose at concentrations between 0 and 30%. cytochrome c appears to exhibit a somewhat greater extent of heme exposure than cytochrome c2 for both th ...1979220233
the amino acid sequence of cytochrome c' from the purple sulphur bacterium chromatium amino acid sequence is proposed for the cytochrome c' from the photosynthetic purple sulphur bacterium chromatium vinosum strain d. it is single polypeptide chain of 131 residues, with haem-attachment cysteine residues at positions 121 and 124. the results discredit an earlier report [dus, bartsch & kamen (1962) j. biol. chem 237, 3083--3093] of a di-haem peptide sequence from this protein. the sequence belongs to the same class as the published alcaligenes and rhodospirillum rubrum cytochrom ...1979220951
[determination of the distance between charges following their photoseparation in chromatophores from r. rubrum]. 1979221054
anomalies in amino acid sequences of small cytochromes c and cytochromes c' from two species of purple photosynthetic bacteria. 1979221823
regulation of cyclic photophosphorylation in rhodospirillum rubrum by the redox state of nicotinamide-adenine dinucleotide.we have investigated the effect of the redox state of added nad on the rates of anaerobic cyclic photophosphorylation which are supported by membrane vesicles isolated from rhodospirillum rubrum. as the redox potential of nad was lowered, the activity decreased according to a typical potentiometric titration. the nernst plot showed an apparent midpoint potential (e'o) of -350 mv and had a slope which corresponded to a two-electron transition. besides, an almost identical potentiometric relations ...1979223636
the chronoamperometric determination of homogeneous small molecule-redox protein reaction rates. 1979224724
properties of the solubilized membrane-bound hydrogenase from the photosynthetic bacterium rhodospirillum rubrum. 1979224815
[free radical centers in the chromatophores and preparations of rhodospirillum rubrum reaction centers].the light-induced free radical esr signals in chromatophores and reaction center preparation of r. rubrum were studied. it has been shown that the properties of the signals in both systems were strictly identical. at the microwave powers higher than 10 mw the esr signal at g approximatley 2.00 is saturated and its asymmetry arises. changes of the esr signal shape may be explained by the superposition of p870+ signal with that from the ubisemiquinone. addition of ferricyanide to chromatophores in ...1979224953
[possible pathways for acetyl-coa formation by purple bacteria].purple sulfur (ectothiorhodospira shaposhnikovii, chromatium minutissimum, lamprobacter modestohalophilus, thiocapsa roseopersicina) and nonsulfur (rhodospirillum rubrum, rhodopseudomonas palustris, rhodopseudomonas spheroides) bacteria are capable of forming acetyl-coa synthetase, phosphotransacetylase and acetokinase independent of the medium composition and growth conditions. in all of the purple sulfur bacteria with an exception of e. shaposhnikovii, the activity of acetokinase is much highe ...1979228168
iron-sulfur clusters in the molybdenum-iron protein component of nitrogenase. electron paramagnetic resonance of the carbon monoxide inhibited state.carbon monoxide inhibits reduction of dinitrogen (n2) by purified nitrogenase from azotobacter vinelandii and clostridium pasteurianum in a noncompetitive manner (kii and kis = 1.4 x 10(-4) and 4.5 x 10(-4) and 7 x 10(-4) atm and 14 x 10(-4) atm for the two enzymes, respectively). the onset of inhibition is within the turnover time of the enzyme, and co does not affect the electron flux to the h2-evolving site. the kinetics of co inhibition of n2 reduction are simple, but co inhibition of acetyl ...1979228701
orientation of the bacteriochlorophyll triplet and the primary ubiquinone acceptor of rhodospirillum rubrum in membrane multilayers determined by esr spectroscopy (i).chromatophores from rhodospirillum rubrum were oriented as multilayers on quartz slides under reducing conditions. irradiation of these multilayers in the resonance cavity of an esr spectrometer at 6 k yielded the spectrum of the bacteriochlorophyll dimer triplet. the relative intesities of the main six lines of the triplet were dependent on the angle subtended by the direction of the external magnetic field with plane of the multilayers. the angular dependence of the intensities of these transi ...1979228709
transfer of light-induced electron-spin polarization from the intermediary acceptor to the prereduced primary acceptor in the reaction center of photosynthetic reaction centers and chromatophores of photosynthetic bacteria strong light-induced emissive esr signals have been found, not only after a flash but also under continuous illumination. the signal, with g = 2.0048 and delta hpp = 7.6 g, is only present under reducing conditions in material in which the primary acceptor, ubiquinone, u and its associated high-spin ferrous ion are magnetically uncoupled. its amplitude under continuous illumination is strongly dependent on light intensity and on m ...1979228714
characterization of the membrane-bound inorganic pyrophosphatase in rhodospirillum rubrum.the membrane-bound inorganic pyrophosphatase (ec from rhodospirillum rubrum has been investigated with the tools of enzyme kinetics, and with two amino acid reagents, n-ethyl-maleimide (malnet) and 4-chloro-7-nitrobenzofurazan (nbf-cl). 1. the concentration of the true substrate, mgppi, was varied with constant concentrations of free mg2+ or ppi. it was observed that mg2+ acted as an activator. 2. heat inactivation of the enzyme at 62 degrees c was slowed down in the presence of mg2+. 3 ...1979230038
[reconstitution of electrogenic function of pyrophosphatase isolated from rhodospirillum rubrum membranes].the membrane vesicles (proteoliposomes) have been reconstituted from phospholipids and inorganic pyrophosphatase (ec isolated from rhodospirillum rubrum chromatophores. an addition of inorganic pyrophosphate (ppi) causes a mg2+-dependent formation of a transmembrane electric potential difference and an uptake of penetrating tetraphenylborate anions by the proteoliposomes. thus, isolated pyrophosphatase, being incorporated into the phospholipid membrane, functions as a mgppi-dependent pr ...1979232668
activation of ribulose 1,5-bisphosphate carboxylase from rhodopseudomonas sphaeroides: probable role of the small subunit.the activation properties of the form i and form ii ribulose 1,5-bisphosphate carboxylases from rhodopseudomonas sphaeroides were examined. both enzymes have a requirement of mg2+ for optimal activity. mn2+, ni2+, and co2+ can also support activity of the form i enzyme, whereas only mn2+ can substitute for mg2+ with the form ii enzyme. the effect of different preincubations on the carboxylase reaction was also examined. both enzymes exhibited a lag when preincubated with other than mg2+ and co2 ...1979316430
[effect of formate on the respiration of different microorganisms].the cells of methylotrophic bacteria (achromobacter parvulus 1, pseudomonas methylica 2 and 20, ps. fluorescens 45, ps. oleovorans 52) and candida methylica 101 grown in a medium with methanol take up oxygen in the presence of formiate. a. parvulus is most resistant to formiate (km = 2.3 +/- 0.5) x 10(-3) m; ki = 4 x 10(-1) m). when grown on cn substrates, these microorganisms cannot oxidize formiate (with an exception of a. parvulus). formiate also serves as a respiration substrate for e. coli ...1979481274
primary structure of a high potential, four-iron-sulfur ferredoxin from the photosynthetic bacterium rhodospirillum tenue.the amino acid sequence of a high oxidation-reduction potential iron-sulfur protein (hipip) isolated from the purple photosynthetic bacterium rhodospirillum tenue has been determined. this is the smallest of the hipip's, containing 63 residues, with only 3 residues apparently conserved in addition to the 4 cluster-binding cysteines. a minimum of four internal genetic gaps is postulated to align tenue high potential iron-sulfur protein with the previously known proteins. it is the most divergent ...1979762147
hydrogen production by the photosynthetic bacterium rhodospirillum rubrum.continuous photosynthetic production of hydrogen by rhodospirillum rubrum in batch cultures was observed up to 80 days with the hydrogen donor, pure lactate or lactic acid-containing wastes, supplied periodically. hydrogen was produced at an average rate of 6 ml/h per g (dry weight) of cells with whey as a hydrogen donor. in continuous cultures with glutamate as a growth-limiting nitrogen source and lactate as a hydrogen donor, hydrogen was evolved at a rate of 20 ml/h per g (dry weight). the co ...197916345375
c nuclear magnetic resonance study of the co(2) activation of ribulosebisphosphate carboxylase from rhodospirillum rubrum.ribulosebisphosphate carboxylase [3-phospho-d-glycerate carboxy-lyase (dimerizing), ec] from rhodospirillum rubrum is activated by co(2) and mg(2+). (13)c nmr spectra were determined for the unactivated enzyme and for enzyme that had been activated by (13)co(2) and mg(2+). in addition to the expected resonance for h(13)co(3) (-)/co(3) (2-) at 161.8 ppm downfield from tetramethylsilane, the spectrum of the activated enzyme shows a broad resonance at 164.9 ppm. analogy with previous nmr s ...197916592618
changes in the regulatory form of rhodospirillum rubrum nitrogenase as influenced by nutritional and environmental factors.the photosynthetic bacterium rhodospirillum rubrum regulates the activity of its nitrogenase (n2ase) by interconverting the enzyme into three distinct enzymatic species: n2ase a (a fully active form) and two regulatory forms, n2ase ractive and n2ase rinactive. n2ase r is distinguished from n2ase a in vitro by the requirement of its fe protein for activation by a mn2+-dependent activating factor. n2ase is converted from the a to the r form in response to certain environmental factors such as carb ...19806103895
reconstitution of biological molecular generators of electric current. inorganic pyrophosphatase.proteoliposomes have been reconstituted from soy-bean phospholipids (asolectin) and inorganic pyrophosphatase isolated from rhodospirillum rubrum chromatophores. in the presence of mg2+ ions, pyrophosphatase proteoliposomes were incorporated into a phospholipid-impregnated teflon filter separating two solutions of an identical electrolyte content. addition of inorganic pyrophosphate to the same compartment as proteoliposomes was found to induce generation of an electric potential difference betw ...19806109629
purification and identification of the factor capable of converting ca2+-atpase into mg2+-atpase present in rhodospirillum rubrum chromatophores. 19806244266
cytochrome c and the evolution of energy metabolism. 19806244618
structure of cytochrome c': a dimeric, high-spin haem protein. 19806250058
two sequence-specific deoxyribonucleases from rhodospirillum rubrum. 19806250895
electron transfer reactions of high-potential iron-sulfur proteins and c-type cytochromes.studies of electron transfer by biological oxidation-reduction proteins frequently focus on the interaction of a particular protein with nonphysiological oxidants and/or reductants. this approach, although valuable, is limited by the size and chemistry of the nonphysiological reactants. to further the understanding of biological electron transfer, we have investigated the interaction of two examples of high-potential iron-sulfur proteins (hipip's) with mitochondrial cytochrome c (horse heart) an ...19806252957
[pyrophosphate-dependent d-fructose-6-phosphate-phosphotransferase in rhodospirillaceae (author's transl)].a pyrophosphate-dependent fructose-6-phosphate phosphotransferase from the photosynthetic bacterium rhodospirillum rubrum was partially purified and characterized in respect to kinetic and regulatory properties. the enzyme had a molecular weight of about 95 000 dalton and required mg2+-ions for catalysis and maintenance of activity. the phosphotransferase was specific for fructose-6-phosphate (f-6-p) and inorganic pyrophosphate (pp) as substrates of the fructose-1,6-bisphosphate-forming reaction ...19806446207
energy-linked reactions catalyzed by the purified atpase complex (f0f1) from rhodospirillum rubrum chromatophores.1. the isolation of f0f1-atpase complex from rhodospirillum rubrum chromatophores by the use of taurodeoxycholate is described. 2. the enzyme preparation contains about 12 polypeptides; five are subunits of the f1 moiety. 3. the atpase activity of the purified enzyme is dependent on the addition of phospholipids. 4. km-vales for mg2+-atp and ca2+-atp are similar to the values obtained for the membrane-bound enzyme. 5. the f0f1-atpase complex is more than 70% inhibited by oligomycin and n,n'-dicy ...19806447594
conversion of the ca2+-atpase from rhodospirillum rubrum into a mg2+-dependent enzyme by 1,n6-etheno atp. 19806448051
atp synthesis catalyzed by the atpase complex from rhodospirillum rubrum reconstituted into phospholipid vesicles together with bacteriorhodopsin. 19806451197
activationless electron transfer processes in biological systems. 19806766403
polyadenylated messenger rnas code for photo reaction center and light-harvesting antenna polypeptides of rhodospirillum rubrum. 19806766405
purification and properties of polynucleotide phosphorylase from photosynthetic bacterium rhodospirillum rubrum.1. polynucleotide phosphorylase [polyribonucleotide: orthophosphate nucleotidyltransferase, ec] was purified to near homogeneity from the photosynthetic bacterium, rhodospirillum rubrum. the purified enzyme had a molecular weight of approximately 160,000, and consisted of two equivalent subunits of approximately 76,000 daltons. it catalyzed the three reactions described below. 2. in the exchange reaction of the beta-phosphate of nucleoside diphosphates with pi by the purified enzyme in t ...19806766923
short-lived delayed luminescence of photosynthesizing organisms. ii. the ratio between delayed and prompt fluorescence as studied by the modulation method.the ratio between the intensities of delayed and prompt fluorescence was studied for different photosynthetic objects under different conditions by modulation method. the method is based on excitation of luminescing objects by light, modulated harmonically, and on a combined study of phase shifts and demodulation coefficients of the luminescence as related to excitation light. the presence of intense delayed emissions was revealed in purple bacteria, ectothiorhodospira shaposhinokovii, rhodospir ...19806768385
photo-induced electron transport and water state in rhodospirillum rubrum is shown that in bacterial chromatophores the pronounced changes in the free water content with a proton spin-spin relaxation time (t2) of 10(-3)--10(-2) s does not influence the efficiency of electron transfer from the photosynthetic reaction centre to the membrane pool of secondary acceptors. an abrupt inhibition of this process occurs only after the loss of the water with faster proton spin-spin relaxation time (t2 of 10(-4) s). the process is reversible. the water fraction in question is ...19806768386
detection of cytochrome b+50 in membranes of rhodospirillum rubrum isolated from aerobically and phototrophically grown cells.1. dark equilibrium potentiometric titrations were conducted on membranes purified from rhodospirillum rubrum in an effort to identify b-type cytochrome components reported in other rhodospirillaceae. in preparations from aerobically grown cells virtually devoid of bacteriochlorophyll a, three components were observed at 560-540 nm. their oxidation-reduction midpoint potentials assigned by computer-assisted analysis were +195, +50 and -110 mv at ph 7.0; each of these fitted closely to theoretica ...19806769433
formation of intracytoplasmic membranes in chemotrophic mecillinam sphaeroplasts of rhodospirillum rubrum.chemotrophically growing cells of rhodospirillum rubrum were transformed into sphaeroplasts of irregular shape under the influence of the penicillin antibiotic mecillinam. on a cell protein basis, respiratory activities of whole sphaeroplasts were slightly decreased as compared with the untreated control. but, on a membrane protein basis various activities of the respiratory chain were largely identical in membrane preparations from untreated cells and sphaeroplasts, respectively. chemotrophical ...19806769673
the dependency of proton extrusion in the light on the developmental stage of the photosynthetic apparatus in rhodospirillum rubrum.the rate of proton extrusion by whole cells of rhodospirillum rubrum is constant on a bacteriochlorophyll basis only above cellular bacteriochlorophyll concentrations of about 10 nmol bacteriochlorophyll per mg cell protein. at specific bacteriochlorophyll cellular levels below this value, the rate of proton extrusion per bacteriochlorophyll increases. correspondingly, membrane preparations isolated from these cells exhibit increases in the rate of proton uptake on a pigment basis. concomitant w ...19806770898
energy transfer and bacteriochlorophyll fluorescence in purple bacteria at low temperature.emission spectra of bacteriochlorophyll a fluorescence and absorption spectra of various purple bacteria were measured at temperatures between 295 and 4 k. for rhodospirillum rubrum the relative yield of photochemistry was measured in the same temperature region. in agreement with earlier results, sharpening and shifts of absorption bands were observed upon cooling to 77 k. below 77 k further sharpening occurred. in all species an absorption band was observed at 751-757 nm. the position of this ...19806772218
[photoinduced changes in dielectric losses in the microwave region in rhodospirillum rubrum photosynthesizing bacteria]. 19806772239
[photoinduced changes in dielectric losses in the microwave region in chromatophores of rhodospirillum rubrum photosynthesizing bacteria]. 19806772240
[linear dichroism of pigments associated with spherical chromatophores. models of orientation in polyacrylamide gels].linear dichroism and orientation of pigments in chromatophores of photosynthetic bacteria chromatium minutissimum and rhodospirillum rubrum using a novel method of orientation in polyacrylamide gel was studied. a model is proposed for orientation of spherical membranes of chromatophores or other similar vesicules. the value of linear dichroism is derived for known deformation of the gel and a certain angle between the transition dipole and a unit vector perpendicular to the membrane plane. the a ...19806772937
carotenoid triplet yields in normal and deuterated rhodospirillum rubrum.quantum yields of carotenoid triplet formation in rhodospirillum rubrum wild type and fully deuterated cells and chromatophores were determined in weak laser flashes for excitation wavelength lambda i = 530 nm (mainly absorbed by the carotenoid spirilloxanthin) and for lambda i = 608 nm (mainly absorbed by bacteriochlorophyll) in the presence and absence of magnetic fields. all experiments were performed at room temperature and in the absence of oxygen. the quantum yield of reaction center bacte ...19806773564
evidence for a correlation between the photoinduced electron transfer and dynamic properties of the chromatophore membranes from rhodospirillum rubrum. 19806773810
effect of l-methionine-dl-sulphoximine on the photoproduction of hydrogen by rhodospirillum rubrum.the repression of photoproduction of hydrogen by ammonia could be relieved by l-methionine-dl-sulfoximine. in the absence of ammonia, hydrogen evolution was inhibited by concentrations of l-methionine-dl-sulfoximine higher than 0.1 mm.19806774882
isolation and sequence of the pyridoxal 5'-phosphate active-site peptide from rhodospirillum rubrum ribulose-1,5-bisphosphate carboxylase/oxygenase.ribulose-1,5-bisphosphate carboxylase/oxygenase from rhodospirillum rubrum was modified with pyridoxal 5'-phosphate and then reduced with sodium borohydride. both carboxylase and oxygenase activities were lost when one molecule of pyridoxal 5'-phosphate was bound per enzyme dimer. peptide maps of modified enzyme showed one n6-(phosphopyridoxal)lysine-containing peptide. this peptide was isolated by gel filtration and cation-exchange chromatography and its sequence determined as ala-leu-gly-arg-p ...19806775695
the photoreaction center of rhodospirillum rubrum mutant strain f24.1.rhodospirillum rubrum strain f24.1 is a spontaneous revertant of nonphototrophic mutant f24 derived from wild-type strain s1. strain f24 shows no detectable photochemical activity and contains, at most, traces of the photoreaction center polypeptides. strain f24.1 has a phototrophic growth rate close to that of the wild-type strain (picorel, r., del valle-tascón, s. and ramírez, j.m. (1977) arch. biophys. biochem. 181, 665-670) but shows little photochemical activity. light-induced absorbance ch ...19806775699
differences in the architecture of cytoplasmic and intracytoplasmic membranes of three chemotrophically and phototrophically grown species of the rhodospirillaceae.freeze-fracture faces of membranes of either chemotrophically or phototrophically grown rhodospirillum rubrum, rhodopseudomonas sphaeroides, and rhodospirillum tenue were analyzed. all three species differed from each other with respect to size as well as numerical density (number per square micrometer) of intramembrane particles. in r. rubrum the number of particles on exoplasmic fracture faces of the cytoplasmic membrane stayed nearly constant (about 900 particles per microns2), but on the pla ...19806776096
polarographic measurement of h2 in aqueous solutions. 19806776845
[thiosulfate oxidation by nonsulfur purple bacteria].the capability to oxidize thiosulfate was studied in 11 cultures of purple bacteria belonging to rhodomicrobium vannielii, rhodopseudmonas viridis, rh. sphaeroides, rh. capsulata, and rhodospirillum rubrum. all the bacteria oxidized thiosulfate under aerobic conditions in the dark. the strains 2r, 8259, a1, a2 and d1 of rh. sphaeroides oxidized thiosulfate under anaerobic conditions in the light, and the process was coupled with carbon dioxide fixation. all the strains contained thiosulfate redu ...19806777642
[conformational mobility and theory of the mössbauer effect in biological systems. (model of a brownian oscillator strongly damped for conformational modes)].specific features of the mössbauer effect on proteins are discussed. it is found that the temperature dependence of recoilless gammaquantum absorption, f'(t), cannot be explained in terms of solid effects or diffusion spectrum broadening in liquids. a sharp decrease in f'(t) at temperature above 200 degrees k that has been found is due to the specificity of the conformational mobility of proteins and due to a smaller correlation time for spacially-confined diffusion of a mössbauer label tracer b ...19806777658
[structural organization of membranes reconstituted from phospholipids and subchromatophore pigment-protein complexes].pigment--protein complexes of the p870 reaction centers and complexes of the bacteriochlorophyll light-harvesting antenna were isolated from the chromatophores of the non-sulfur purple bacterium rhodospirillum rubrum by solubilization with detergents. the proteoliposomes containing the reaction centers or reaction centers and the light-harvesting antenna as well as liposomes formed from phospholipids were obtained by a self-assembly procedure using seya bean phospholipids. the freeze-fracture st ...19806786374
[cyclic electron transfer and membrane potential generation in chromatophores on non-sulfur bacteria rhodospirillum rubrum].the uptake of permeant anions by cells and chromatophores of the non-sulfur purple bacteria r. rubrum has been studied. antimycin a causes biphasic inhibition of the light-induced uptake of tetraphenylborate anions (tb-) by the cells and the isolated chromatophores incubated under anaerobic conditions. the first phase is observed at small concentrations of antimycin and is due to its effect as an inhibitor of the cyclic electron transfer. the second phase is observed at concentrations higher tha ...19806783130
dinitrogen-fixing bacteria: computer-assisted identification of soil isolates.dinitrogen-fixing (acetylene-reducing) bacteria may be readily isolated from soils but extensive biochemical or immunobiological testing, or both, are required to identify them absolutely. a computer-assisted scheme for identification of nine genera of dinitrogen-fixing bacteria was developed and tested. the computer program is based on interpretation of the 70 biochemical tests of the api 20e and 50e, supplemented with tests for acetylene reduction, nitrate and nitrite reduction, catalase, oxid ...19807214218
2-carboxy-d-hexitol 1,6-bisophosphate: an inhibitor of d-ribulose 1,5-bisphosphate carbosylase/oxygenase. 19807362236
labeling of chromatophore membranes and reaction centers from the photosynthetic bacterium rhodospirillum rubrum with the hydrophobic marker 5-[125i]iodonaphthyl-1-azide..chromatophores of the photosynthetic bacterium rhodospirillum rubrum and isolated reaction centers were labeled with the lipophilic membrane marker 5-[125i]iodonaphthyl-1-azide. the two smaller reaction center proteins l and m bind more label than the larger subunit h, a fact supporting the proposed localisation of the 3 subunits obtained with hydrophilic labels. besides these integral proteins the lipids, among them mainly the pigments and the quinones, are highly labeled suggesting a hydrophob ...19807397129
primary structures of high potential, four-iron-sulfur ferredoxins from the pruple sulfur photosynthetic bacteria, thiocapsa roseopersicina and chromatium gracile. 19817451471
structure of the heptose region of lipopolysaccharies from rhodospirillum tenue.there is a common structure (core region) in the lipopolysaccharides of rhodospirillum tenue. it is composed of a branched trisaccharide of l-glycero-d-mannoheptose (and of 2-keto-3-deoxyoctonate), as revealed by methylation analyses of degraded polysaccharides of four different r. tenue strains. the structure is similar or might even be identical to the inner core of enterobacterial o antigens. in addition, each of the four r. tenue lipopolysaccharides contains a strain-specific region that con ...19817462142
[isolation and properties of the pigment-protein complex (protochlorophyllide - holochrome) from etiolated leaves of corn sprouts].a pigment -- protein complex was isolated from etiolated leaves of corn sprouts using treatment by the detergent triton x-100, ultracentrifugation and gel-filtration. the complex has a molecular weight of 50000 and upon illumination can convert protochlorophyllide (pchld) into chlorophyllide (chld). the low temperature fluorescence spectra of dark preparations reveal maxima of pchld 632 (photo-inactive form) and pchld 653 (photo-active form). upon illumination pchld 653 is converted into chld 68 ...19817248372
radioprotective and haemopoietic effects of some lipopolysaccharides from rhodospirillaceae species in mice.lipopolysaccharides (lps) from various rhodopseudomonas and rhodospirillum species were tested for their radioprotective efficiency against x-irradiation and for their influence on the growth of spleen colony forming units (cfu-s) in mice. the lps from rhodopseudomonas gelatinosa dr2 gave a high survival rate. it also favoured cfu-s formation and erythroid differentiation.19817327249
composition and development of the bacterial photosynthetic apparatus. 19817032006
x-ray diffraction studies on chromatophore membrane from photosynthetic bacteria. i. diffraction pattern of the photoreaction unit isolated from rhodospirillum rubrum chromatophore and some characteristics of the structure.the x-ray diffraction pattern from chromatophore membranes of a photosynthetic bacterium, rhodospirillum rubrum, indicates that a highly organized protein assembly exists in the membrane. the x-ray scatterer was solubilized from chromatophores by a mixture of cholate and deoxycholate. the basic component was identified as the photoreaction unit, which consists of light-harvesting bacteriochlorophyll proteins and a reaction center. the radial autocorrelation function, calculated directly from the ...19816783640
a low-angle laser light scattering study of the association behavior of a major membrane protein of rhodospirillum rubrum chromatophore at various concentrations of sodium dodecyl sulfate where polypeptides derived from water-soluble globular proteins are solubilized monomerically.the major membrane protein of rhodospirillum rubrum chromatophore could be solubilized in the presence of free sodium dodecyl sulfate (sds) in concentration above 0.8 mm. at this concentration, the protein was highly associated to give a weight-averaged molecular weight as high as one million as determined by the low-angle laser light scattering technique. with the increase of free sds concentration, the aggregates were progressively dissociated to give a molecular weight of 8300 at the critical ...19816784770
[charge transfer in the primary processes of photosynthesis].transmission of electric charges generated by light in the unbranching chain of electron transport is under consideration. recombination of electrons and holes and possibility of reverse processes are considered. expression for the efficiency of steady-state charge separation is obtained. example of the reaction centre of bacterial photosynthesis is considered. all this permits to connect the signals of microwave photolosses with the destination of the electron on distant electron carriers.19816784776
[study of microwave photolosses in chromatophores of photosynthesizing rhodospirillum rubrum bacteria].the study of photoinduced dielectric losses at frequency 10(10) c/s as function of samples humidity, heating and chemical treatment, intensity and wavelength of light is reported. the signals of microwave losses and differential spectrum signals are compared. the authors attribute the photolosses observed to the electrons localised in the realm between the primary and secondary acceptors during their reduction, probably being in the conductance quasiband of proteins in the photosynthetic reactio ...19816784778
control of 5-aminolevulinic acid synthetase activity in phototrophic facultative bacteria. purification and some properties of the enzyme from rhodospirillum rubrum. 19816786365
[carbamyl phosphate and citrulline formation by phototrophic bacteria].the purple bacteria ectothiorhodospira shaposhnikovii and rhodospirillum rubrum are capable of synthesizing citrulline in the presence of ammonium hydrocarbonate, ornithine, atp and mg2+ ions. citrulline biosynthesis by these phototrophic bacteria is presumed to be catalysed by carbamate kinase and ornithine transcarbamoylase. therefore, certain phototrophic bacteria can assimilate carbon dioxide and ammonia for biosynthesis of amino acids, in particular, citrulline and, apparently, arginine.19816798373
propionate formation in rhodospirillum rubrum under anaerobic dark conditions.experiments with 14c labelled propionyl-coa, methylmalonyl-coa and succinyl-coa showed that these compounds are intermediates of propionate synthesis in fermentative metabolism of rhodospirillum rubrum. the rate of propionate and succinate production is dependent on the co2 concentration of the medium. there is, however, no evidence for a transcarboxylation, and high concentrations of propionate in the medium did not inhibit propionate synthesis as in the case in propionibacteria. pep-carboxykin ...19816798770
borate inhibits activation of inactive dinitrogenase reductase from rhodospirillum rubrum.borate and aminophenylboronic acid were tested as inhibitors of activation of inactive dinitrogenase reductase from rhodospirillum rubrum. inhibition was specific for activation because activity of the active form of the enzyme was not inhibited. inhibition showed the ph-dependence expected if borate inhibits by binding to cis-hydroxy groups of the modifying group found on the inactive enzyme.19816798967
[kinetics of ubisemiquinone redox changes in primary reactions of bacterial photosynthesis].absorbance changes at 450 nm of the semiquinone form of the secondary electron acceptor were studied in chromatophores of rhodospirillum rubrum. when chromatophores are illuminated by a series of single turnover flashes ubisemiquinone is formed and destroyed on alternate flashes at ambient redox potential from 100 to 250 mv. a simple kinetic model of the binary oscillations is suggested. on the base of the model it is shown that the rate constant of electron transfer from primary to secondary qu ...19816789145
[kinetics of the generation of a photo-induced electric potential in chromatophores of photosynthetizing bacteria].flash-induced formation of an electric potential difference (delta psi) was monitored by a direct method in chromatophores associated with the collodion phospholipid membrane. in rhodospirillum rubrum and rhodopseudomonas sphaeriodes chromatophores, the kinetics of delta psi generation exhibit fast (tau less than or equal to 0.3 microseconds) and slow (tau congruent to 200 microseconds) phases, the latter observed in the presence of exogenous quinones. comparison of the kinetic and potentiometri ...19816789146
sequences of tryptic peptides containing five cysteinyl residues of ribulosebisphosphate carboxylase/oxygenase from rhodospirillum rubrum. 19816789776
[photooxidation and light-induced transport of phenazine methosulfate in chromatophores of purple bacteria].the light-induced interaction of phenazine methosulfate (pms) with chromatophores of the purple bacteria rhodospirillum rubrum and rhodopseudomonas sphaeroides was studied, using an ion-specific electrode. illumination caused an initial rapid increase in the concentration of methylphenazinium cation (mp+) and a subsequent slow (1-3 min) decrease of the mp+ concentration to a low steady level. the rapid phase of the light-induced mp+ concentration change is specifically enhanced by ascorbate. the ...19816789897
effect of oxygen on acetylene reduction by photosynthetic bacteria.the effect of dissolved oxygen concentration on nitrogenase activity was studied in three species of photosynthetic bacteria. the o2 concentration in the cell suspension was measured with an o2 electrode inserted into the reaction vessel. acetylene reduction by whole cells of rhodopseudomonas capsulata, rhodospirillum rubrum, and chromatium vinosum strain d was inhibited 50% by 0.73, 0.32, and 0.26 microm o2, respectively. the inhibition of the activity by o2 in r. capsulata usually was reversed ...19816790517
[role of cofactors in membrane potential generation by rhodospirillum rubrum chromatophores incorporated in a teflon filter].the chromatophores of the bacterium rhodospirillum rubrum were incorporated into a teflon filter impregnated with a decane solution of phospholipids and the light-induced electric potential difference (delta psi) between the aqueous phases separated by the filter was measured. the generation of delta psi in such a system at continuous light requires the presence of cofactors, i. e. artificial electron donors and acceptors. these cofactors provide for a steady-state flow of e by regenerating the ...19816791704
steady-state measurements of delta ph and delta psi in rhodospirillum rubrum chromatophores by two different methods. comparison with phosphorylation potential.the ph gradient, delta ph, and the membrane potential, delta psi, formed during light-induced electron transport in rhodospirillum rubrum chromatophores were measured by two independent methods: (a) using specific electrodes to monitor light-dependent uptake of nh4cl and scn- at chromatophore concentrations of about 0.1 mg bacteriochlorophyll/ml and (b) using 9-aminoacridine and 8-anilinonaphthalenesulfonic acid as fluorescent probes for delta ph and delta psi, respectively, at chromatophore con ...19816793067
fast stages of photoelectric processes in biological membranes. iii. bacterial photosynthetic redox system.chromatophores of photosynthetic bacteria rhodospirillum rubrum, rhodopseudomonas sphaeroides and chromatium minutissimum were associated with a collodion film impregnated with a decane solution of asolectin. a very short light flash inducing a single turnover of the chromatophore photosynthetic redox system was found to induce the formation of an electrical potential difference amounting to 60 mv, directed across the film as measured with an orthodox electrometer technique. the main phase of th ...19816793358
ferredoxin excreted from photosynthetic bacterium, rhodospirillum rubrum: purification and properties.when the photoheterotroph, rhodospirillum rubrum, was grown in the light, ferredoxin was excreted from the cells in a significant amount, as well as hydrogenase. the extracellular ferredoxin was purified to a homogeneous state. the molecular weight was approximately 9,000, and the oxidation-reduction mid-potential was -0.29 v (n=1) at ph 7.0 and 25 degrees c. the amino acid composition was different from those of the intracellular ferredoxins, which were already known. the contents of non-heme i ...19816793564
[kinetic model of the operation of a 2-electron switch in the photosynthetic reaction center of bacteria].a mathematical model, describing the binary oscillation of the concentration of semiquinone form of the secondary acceptor (ubiquinone) in photosynthetic reaction center of purple bacteria is proposed. this model takes into account both the changes of the ubiquinone state when the chromatophores are subjected to short flashes of light, and the successive dark relaxation of the semiquinone form. the model allows to calculate such characteristics as the dependence of the flash number, the stationa ...19816795442
[study of chromophore dynamics by means of rayleigh scattering of mossbauer radiation].the temperature dependence of rayleigh scattering of mössbauer radiation was studied for two samples of the chromatophores with different relative humidity (p/ps = 0.35 and 0.94). new type of motion--the transitions between conformational substates was found above 200 degrees k. the model was developed to describe conformational motion in the membranes and membrane proteins. a new formula was derived for the debye--waller factor in accordance with this model. the model proposes the existence of ...19816795443
the effects of bivalent cations on ribulose bisphosphate carboxylase/oxygenase.the half-saturation constants for binding of the bivalent cations (mg2+, ni2+, co2+, fe2+ and mn2+) to ribulose bisphosphate carboxylase/oxygenase from glycine max and rhodospirillum rubrum were measured. the values obtained were dependent on the enzyme and the cation present, but were the same for both oxygenase and carboxylase activities. ribulose bisphosphate rather than its cation complex was the true substrate. the kinetic parameters vmax.(co2), vmax.(o2), km(co2), km(o2), and k1(o2) were d ...19816796054
[low-temperature device for fluorimetric studies]. 19816796132
lateral organization of proteins in the chromatophore membrane of rhodospirillum rubrum studied by chemical cross-linking.the organization of proteins in the chromatophore membrane, particularly of the reaction center and the light-harvesting polypeptide, was examined by the use of a hydrophobic and a hydrophilic cross-linking reagent, namely dsp (dithiobis-succinimidyl propionate) and glutaraldehyde. the linkage of proteins was studied by sds polyacrylamide pore gradient electrophoresis. dsp was shown to link proteins within the core of the membrane. the subunit h of the reaction center is linked with dsp at a low ...19816796574
inactivation of ribulosebisphosphate carboxylase/oxygenase from rhodospirillum rubrum and spinach with the new affinity label 2-bromo-1,5-dihydroxy-3-pentanone 1,5-bisphosphate. 19816797428
inhibition of nitrogenase activity by nh+4 in rhodospirillum rubrum.nitrogenase activities and the patterns of in vivo inhibition of nitrogenase by nh+4 were compared in rhodospirillum rubrum grown under several conditions of nitrogen availability. in cells grown on n2 or glutamate plus n2, nitrogenase activity was relatively low and was totally inhibited by added nh+4 in 15 to 20 min. in contrast, cells grown on glutamate alone displayed higher nitrogenase activity, and nh+4 had very little effect. cells grown on limiting amounts of nh+4 had lower nitrogenase a ...19816780531
the inhibition of photosynthetic electron transfer in rhodospirillum rubrum by n ,n' -dicyclohexylcarbodiimide.n ,n' -dicyclohexylcarbodiimide (dccd) at concentrations above 0.1 mm inhibits light-induced generation of a membrane potential in the course of cyclic and non-cyclic electron transfer, as well as light-induced oxygen uptake due to interaction of photoreduced secondary (loosely bound) ubiquinone with o2 in rhodospirillum rubrum chromatophores. similarly to o-phenanthroline, dccd blocks the electron transfer in the chromatophores between the primary (tightly bound) and secondary ubiquinones.19816781540
nuclear magnetic resonance studies of rhodospirillum rubrum cytochrome c'.cytochrome c' from rhodospirillum rubrum has been studied by proton magnetic resonance (nmr) at 270 mhz. the ph and temperature-dependence properties as well as proton water relaxation enhancement and bulk susceptibility measurements were examined. we conclude that the fifth ligand to the iron is histidine. the ph-dependent shift of the heme methyl resonances of the ferric protein shows pka's at 5.8 and 8.7. the low-ph equilibrium causes only minor changes in the properties of the protein. howev ...19816258631
comparison of the redox reactions of various types of cytochrome c with iron hexacyanides.the dynamic behavior of various types of cytochromes c in the redox reaction with iron hexacyanides was studied using a temperature-jump method in order to elucidate the molecular mechanism of the redox reaction of cytochromes with their oxidoreductants. transmittance after the temperature jump changed through a single exponential decay for all cytochromes investigated. under a constant concentration of anion, the redox reaction of various types of cytochrome c with iron hexacyanides was analyze ...19816258647
biosynthesis of bacterial glycogen: purification and structural properties of rhodospirillum tenue adenosine diphosphate glucose synthetase.adenosine diphosphate glucose synthetase from the photosynthetic bacterium rhodospirillum tenue has been purified greater than 95%. the molecular weight of the enzyme is approximately 215,000, with a subunit molecular weight of about 51,000. the enzyme appears to be composed of four similar if not identical subunits. although the amino acid composition of the enzyme is similar to that of escherichia coli and salmonella typhimurium, no apparent homology has been observed between their n-terminal ...19816263861
on the evolutionary relationship of the 4-alpha-helical heme proteins. the comparison of cytochrome b562 and cytochrome c'.the atomic models of the cytochrome b562 and cytochrome c' monomers have been compared. when the respective heme groups are superimposed, the four alpha-helices of each nearly coincide. four aromatic side chains, including the heme ligands, and a methionine occur in spatially equivalent positions in contact with the heme groups. this structural evidence suggests that the two cytochrome families may have diverged from a common molecular ancestor.19816267021
biosynthesis of bacterial glycogen: activator specificity of the adenosine diphosphate glucose pyrophosphorylases from the genus rhodospirillum.the adenosine diphosphate (adp) glucose pyrophosphorylases from rhodospirillum fulvum, rhodospirillum molischianum, and rhodospirillum tenue were partially purified, and their kinetic properties were studied. the enzyme from the three organisms was found to be activated by pyruvate and thus was similar to the rhodospirillum rubrum enzyme that had been previously studied (c. e. furlong, and j. preiss, j. biol. chem. 244:2539-2548, 1979). the enzymes from r. fulvum, r. molischianum, and r. tenue w ...19816268603
epr studies of a nonphotosynthetic mutant of rhodospirillum rubrum. 19816271071
incorporation of atp synthetase into long-term stable liposomes of a polymerizable synthetic sulfolipid. 19816271594
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