PMID(sorted descending)
rna ligase in bacteria: formation of a 2',5' linkage by an e. coli extract.ligase activity was detected in extracts of escherichia coli, clostridium tartarivorum, rhodospirillum salexigens, chromatium gracile, and chlorobium limicola. ligase was measured by joining of trna halves produced from yeast ivs-containing trna precursors by a yeast endonuclease. the structure of trnatyr halves joined by an e. coli extract was examined. the ligated junction is resistant to nuclease p1 and rnaase t2 but sensitive to venom phosphodiesterase and alkaline hydrolysis, consistent wit ...19836347395
reconstruction of photosynthetic, cyclic electron transport system from photoreaction unit, ubiquinone-10 protein, cytochrome c2 and polar lipids purified from rhodospirillum was previously reported that in chromatophores of rhodospirillum rubrum, reaction center, which consists of three kinds of protein (mm, about 78k), is a small fragment of a large protein complex (pru; photoreaction unit), which contains six other kinds of protein including light-harvesting bacteriochlorophyll protein, has mm of about 700k and is free of phospholipid [j. biochem. 86, 1211-1224 (1979); 94, 1815-1826 (1983(]. in the present study, the photosynthetic, cyclic electron transport sy ...19846325401
identification of nitrogenase and carboxylase genes in the photosynthetic bacteria and cloning of a carboxylase gene from rhodopseudomonas sphaeroides.the presumptive genes for the ribulose 1,5-bisphosphate carboxylase large subunit and for nitrogenase-specific components from rhodopseudomonas sphaeroides and several other photosynthetic bacteria were identified and located by interspecific probing. restriction digests of r. sphaeroides genomic dna were hybridized under stringent conditions to cloned dna from rhodospirillum rubrum (plasmid prr2119 carrying the carboxylase gene) and klebsiella pneumoniae (psa30 carrying the nitrogenase genes). ...19836319239
the dibromothymoquinone effect on membrane potential generation in rhodospirillum rubrum chromatophores.2,5-dibromo-3-methyl-6-isopropyl benzoquinone (dbmib) inhibits the light-dependent membrane potential generation in rhodospirillum rubrum chromatophores. the inhibition is relieved by electron donors and is obviously due to oxidation of the photosynthetic electron transfer chain components. in addition, high dbmib concentrations elicit another effect probably caused by disruption of quinone functions in chromatophores. however, in quinone-depleted chromatophores and proteoliposomes containing th ...19836316108
characterization of a rhodospirillum rubrum plasmid: loss of photosynthetic growth in plasmidless strains.a single plasmid of 55 kilobases was found in crude cell lysates of each of nine strains of rhodospirillum rubrum. restriction endonuclease analysis showed identical fragment patterns with a given nuclease for all plasmids except one, for which an additional ecori site was observed. elimination of the plasmid required that the cells be passaged several times in 25 mm calcium-containing medium, followed by at least two passages under photosynthetic growth conditions in low-calcium medium before t ...19836313617
two types of essential carboxyl groups in rhodospirillum rubrum proton atpase.two different types of essential carboxyl groups were detected in the extrinsic component of the proton atpase of rhodospirillum rubrum. chemical modification of r. rubrum chromatophores or its solubilized atpase by woodward's reagent k resulted in inactivation of photophosphorylating and atpase activities. the apparent order of reaction was nearly 1 with respect to reagent concentration and similar k1 were obtained for the soluble and membrane-bound atpases suggesting that inactivation was asso ...19836307154
nitrogen fixation and ammonia switch-off in the photosynthetic bacterium rhodopseudomonas viridis.rhodopseudomonas viridis atcc 19567 grows by means of nitrogen fixation in yeast extract-n2 or nitrogen-free medium when sparged with 5% co2 and 95% n2 in the light at 30 degrees c. acetylene reduction assays for nitrogenase activity revealed an initially high level of activity during early-logarithmic growth phase, a lower plateau during mid- to late-logarithmic phase, and a dramatic reduction of activity at the beginning of the stationary phase. when viewed by electron microscopy, nitrogen-fix ...19836305906
individual 1h-nmr assignments for the heme groups and the axially bound amino acids and determination of the coordination geometry at the heme iron in a mixture of two isocytochromes c-551 from rhodopseudomonas gelatinosa.this paper describes chemical and physicochemical studies of two small isocytochromes c-551 (approx. 9000 dalton) from rhodopseudomonas gelatinosa. in spite of numerous amino acid substitutions in the n-terminal half of the sequence the two isoproteins could not be separated by the procedures used, presumably because they have identical size, charge and isoelectric points. individual assignments of the 1h-nmr lines of heme c and the axial ligands to the heme iron were therefore obtained by nucle ...19836297597
[generation of the differences of the electric potentials by rhodospirillum rubrum reaction center complexes devoid of the heavy subunit].the electrogenic activity of rhodospirillum rubrum p870 reaction center complexes devoid of the heavy (h) subunit and retaining the light (l) and medium (m) subunits, was studied. the proteoliposomes containing such reaction center complexes were formed by a self-assembly procedure, using soya bean phospholipids. in the presence of ca2+ the reaction center proteoliposomes were incorporated into a phospholipid-impregnated teflon filter separating two solutions of identical composition. after addi ...19826293591
ribulose-1,5-bisphosphate carboxylase: enzyme-catalyzed appearance of solvent tritium at carbon 3 of ribulose 1,5-bisphosphate reisolated after partial reaction.when ribulose 1,5-bisphosphate is allowed to react with carbon dioxide in tritiated water in the carboxylation reaction catalyzed by ribulose-1,5-bisphosphate carboxylase from rhodospirillum rubrum, the ribulose 1,5-bisphosphate reisolated after partial reaction is found to be labeled. the specific radioactivity of the remaining substrate pool rises during the course of the reaction. experiments in deuterium oxide show that the isotopic label resides on carbon 3. earlier failures to detect this ...19826293539
correlations between structural and spectroscopic properties of the high-spin heme protein cytochrome c'.the cytochromes c' are a class of heme proteins whose native spectroscopic properties have been suggested to represent a quantum mechanical admixture of intermediate-(s = 3/2) and high-(s = 5/2) spin states. here features of the cytochrome c' heme environment, as revealed by x-ray crystallographic studies of the dimeric cytochrome c' from rhodospirillum molischianum, are related to the observed spectroscopic properties. the environment of the heme group in cytochrome c' supports the existence of ...19826293536
crystallographic structure of rhodospirillum molischianum ferricytochrome c' at 2.5 a resolution. 19816279876
metal coordination centres of class ii cytochromes c.the class ii cytochromes rhodospirillum molischianum cytochrome c', rhodopseudomonas palustris cytochrome c556 and agrobacterium tumefaciens (b2a) cytochrome c556 have been investigated with a variety of spectroscopic techniques. the cytochrome c' was found to be high-spin and the two cytochromes c556 were found to be mainly low-spin and sx-coordinate with the fifth and sixth ligands being histidine and methionine. the implications of the different types of iron coordination are discussed.19826279397
incorporation of atp synthetase into long-term stable liposomes of a polymerizable synthetic sulfolipid. 19816271594
epr studies of a nonphotosynthetic mutant of rhodospirillum rubrum. 19816271071
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
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: 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
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
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
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
two sequence-specific deoxyribonucleases from rhodospirillum rubrum. 19806250895
structure of cytochrome c': a dimeric, high-spin haem protein. 19806250058
cytochrome c and the evolution of energy metabolism. 19806244618
purification and identification of the factor capable of converting ca2+-atpase into mg2+-atpase present in rhodospirillum rubrum chromatophores. 19806244266
preparative purification of the subunits of chloroplast and rhodospirillum rubrum coupling factors by flat-bed electrofocusing in granulated gels.a rapid method for the preparative purification of the subunits of oligomeric proteins like chloroplast and rhodospirillum rubrum coupling factors is presented. it involves the dissociation of the protein in urea and the separation of its subunits by isoelectric focusing in flat-beds of sepharose cl-4b or sephadex g-75 superfine, in the presence of urea and in an overnight run. using this procedure in the ph range 5-7, we have purified to homogeneity the alpha, beta and delta subunits of chlorop ...19846240506
response of soluble and membrane-bound f1 atpase of rhodospirillum rubrum to the photoaffinity label 8-azido atp.soluble atpase (f1 atpase) and membrane-bound atpase (chromatophores) of rhodospirillum rubrum have been photoaffinity labeled with 8-azidoadenosine 5'-triphosphate (8-n3atp). the specific binding of 8-n3atp to nucleotide binding sites of the chromatophore-bound enzyme is established by competition experiments and it is suggested that hydrolysis and phosphorylation involve the same nucleotide binding sites. the experimental results also indicate that the function of the coupling factor f1 is inf ...19836237651
[reconstruction of highly purified proton-translocating pyrophosphatase from rhodospirillum rubrum].using the freezing-thawing procedure, a highly purified preparation of ppase from r. rubrum chromatophore membranes was incorporated into soybean phospholipid liposomes. the activity of reconstituted ppase was increased in the presence of the uncoupler, fccp, and the antibiotics, valinomycin (+kcl) and nigericin (+kcl). oligomycin did not exert any inhibiting action, while imidodiphosphate and naf significantly decreased the activity of the ppase incorporated into the liposomes. preincubation of ...19836226320
the interaction of carboxyl group reagents with the rhodospirillum rubrum f1-atpase and its isolated beta-subunit.the carboxyl group reagents dicyclohexylcarbodiimide (dccd) and n-ethoxycarboxyl-2-ethoxy-1,2-dihydroquinoline (eedq) inactivate the soluble rhodospirillum rubrum f1-atpase (rrf1). the inactivation is both time- and concentration-dependent and also ph-dependent, being more marked at acid ph. under the same conditions, n-ethyl-5-phenylisoxazolium 3'-sulfonate causes almost no inactivation of the rrf1-atpase. complete inhibition of the enzyme activity requires the binding of 1 mol of dccd/mol of r ...19836219997
the interaction of 4-chloro-7-nitrobenzofurazan with rhodospirillum rubrum chromatophores, their soluble f1-atpase, and the isolated purified beta-subunit.atp synthesis and hydrolysis by rhodospirillum rubrum chromatophores as well as the soluble rrf1-atpase activity are inhibited by 4-chloro-7-nitrobenzofurazan (nbd-c1) in a dithiothreitol-reversible manner. using the method earlier developed in these chromatophores to remove specifically the beta-subunit from their membrane-bound rrf1 leaving all other subunits attached to the resulting inactive beta-less chromatophores (philosoph, s., binder, a., and gromet-elhanan, z. (1977) j. biol. chem. 252 ...19836219996
antibodies to the f1-atpase of rhodospirillum rubrum and its purified native beta-subunit: inhibition of atp-linked activities in r. rubrum and in lettuce.1. antibodies prepared against the rhodospirillum rubrum f1-atpase (rrf1) and its purified, native-beta-subunit, exhibited cross-reactivity with the following soluble preparations of r. rubrum atpase: rrf0 . f1, rrf1 and the beta-subunit. anti-rrf1, but not anti-beta antibodies, also formed precipitin lines with soluble beta-less rrf1, indicating that antigenic determinants of both the beta-subunit and the other four rrf1-subunits are expressed in the whole rrf1 molecule. both antibodies aggluti ...19816210525
polyadenylated mrna from the photosynthetic procaryote rhodospirillum cellular rna extracted from rhodospirillum rubrum cultured in butyrate-containing medium under strict photosynthetic conditions to the stationary phase of growth has been fractionated on an oligodeoxythymidylic acid-cellulose column into polyadenylated [poly(a)+] rna and poly(a)- rna fractions. the poly(a)+ fraction was 9 to 10% of the total bulk rna isolated. analysis of the poly(a)+ rna on a denaturing urea-polyacrylamide gel revealed four sharp bands of rna distributed in heterodisperse ...19846199342
n-terminal sequences of subunits l and m of the photosynthetic reaction centre from rhodospirillum rubrum g-9+. separation of the subunits by gel filtration on hydroxypropylated sephadex g 100 in organic solvents.a new method has been developed by which subunits l and m of the photosynthetic reaction centre from rhodospirillum rubrum g-9+ can be obtained in pure form, starting form freeze-dried chromatophore membranes. the method employs extraction into a mixture of chloroform/methanol and gel permeation chromatography on a column of hydroxypropylated sephadex g 100. cross-contamination of the purified subunits was less than 5% (mol/mol), as estimated by manual edman degradation. automated edman degradat ...19836199280
neutron small angle scattering of matched proteoliposomes with incorporated f0f1 atpase complex from rhodospirillum rubrum fr1. an approach to the structure of membrane proteins in their natural environment.purified f0f1 atpase from rhodospirillum rubrum fr1 has been incorporated into lipid vesicles from the partially deuterated phospholipid dimyristoylglycerophosphocholine (dmpc-d54). these proteoliposomes were able to carry out energy transducing reactions. the incorporation of the membrane protein was controlled by freeze fracture electron microscopy. a method for structural research of the membrane protein in its natural environment has been developed by means of neutron small angle scattering. ...19836195064
immunochemical relationship of the major outer membrane protein of rhodopseudomonas sphaeroides 2.4.1 to proteins of other photosynthetic bacteria.immunoblots of sodium dodecyl sulfate-polyacrylamide gels derived from outer membrane preparations of various strains of rhodopseudomonas sphaeroides revealed polypeptides which cross-reacted with antibody directed against the major outer membrane protein of r. sphaeroides 2.4.1. immunochemical quantitation of the major outer membrane protein of strain 2.4.1 showed approximately 5.5 x 10(4) molecules per cell whether cells were grown chemoheterotrophically or photoheterotrophically. rhodospirill ...19836188744
chemical modification of the beta-subunit isolated from a membrane-bound fo-f1-atp synthase: modification by 4-chloro-7-nitrobenzofurazan does not inhibit restoration of atp synthesis or hydrolysis. 19826184056
isolation and purification of an active gamma-subunit of the f0.f1-atp synthase from chromatophore membranes of rhodospirillum rubrum. the role of gamma in atp synthesis and hydrolysis as compared to proton translocation.we have earlier shown that extraction of rhodospirillum rubrum chromatophores with licl removed completely the beta-subunit of their coupling factor atpase complex leaving the other four subunits attached to the membrane (philosoph, s., binder, a., and gromet-elhanan, z. (1977) j. biol. chem. 252, 8747-8752). further treatment of these beta-less chromatophores with libr, under the described optimal conditions, resulted in specific removal of one additional subunit, the gamma-subunit, and both su ...19826181058
biosynthesis of bacterial glycogen: purification and structural and immunological properties of rhodopseudomonas sphaeroides adpglucose synthetase.adpglucose synthetase from the photosynthetic bacterium rhodopseudomonas sphaeroides was purified to greater than 95% purity. the molecular weight of the r. sphaeroides enzyme, as determined by sucrose density gradient ultracentrifugation, was approximately 204,000. the subunit molecular weight of the enzyme based on sodium dodecyl sulfate-gel electrophoresis was 46,000. although the amino acid composition of the enzyme was similar to that found for the enzymes from escherichia coli, salmonella ...19826178721
the nucleotide sequence of phenylalanine trna and 5s rna from rhodospirillum rubrum.the complete nucleotide sequence of trnaphe and 5s rna from the photosynthetic bacterium rhodospirillum rubrum has been elucidated. a combination of in vitro and in vivo labelling techniques was used. the trnaphe sequence is 76 nucleotides long, 7 of which are modified. the primary structure is typically prokaryotic and is most similar to the trnaphe of escherichia coli and anacystis nidulans (14 differences of 76 positions). the 5s ribosomal rna sequence is 120 nucleotides long and again typica ...19816174192
sequential removal and reconstitution of subunits beta and gamma from a membrane-bound fo.fl-atp synthase. 19816171271
purification and immunological studies of glutathione reductase from rat liver. evidence for an antigenic determinant at the nucleotide-binding domain of the enzyme.glutathione reductase has been purified to homogeneity by a method which is an improvement of an earlier procedure (carlberg, i. and mannervik, b. (1975) j. biol. chem. 250, 5475-5480). the new steps in the purification scheme include affinity chromatography on 2',5' adp-sepharose 4b. antibodies to glutathione reductase from rat liver were raised in rabbits and used for analysis of the enzyme by quantitative 'rocket' immunoelectrophoresis. glutathione reductase from human erythrocytes, porcine e ...19816170346
membrane-bound inorganic pyrophosphatase. 19846151664
derepression of nitrogenase by addition of malate to cultures of rhodospirillum rubrum grown with glutamate as the carbon and nitrogen source.rhodospirillum rubrum grown in continuous culture with glutamate as the sole fixed c and n source produced no nitrogenase, and the cultures were characterized by high extracellular ammonium concentrations. addition of organic acids derepressed nitrogenase. glutamate dehydrogenase, glutamine synthetase, glutamate synthase, malate dehydrogenase, nitrogenase, and ammonium were assayed before and after malate addition.19846145702
h2 metabolism in photosynthetic bacteria and relationship to n2 fixation.the photosynthetic bacteria can evolve h2 in the light through a nitrogenase-mediated reaction. the nitrogenase enzyme in the photosynthetic bacteria is similar to other nitrogenases. it is made of two soluble components: a) the fe protein (dinitrogenase reductase or component ii) which receives electrons from ferredoxin, and b) the mo-fe protein (dinitrogenase or component i) on which the substrates (including protons) are reduced. in photosynthetic bacteria, the physiological regulation of nit ...19836139053
[effect of 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone, a ubiquinone analog, and sh-reagents on the electrogenic function of pyrophosphatase from rhodospirillum rubrum chromatophores].inorganic pyrophosphate-induced membrane potential generation in rhodospirillum rubrum chromatophores is inhibited by 2,5-dibromo-2-methyl-6-isopropyl-p-benzoquinone (dbmib). the inhibition is increased by menadione and dithionite and is not relieved by ascorbate; this effect is probably due to a displacement of the intrachromatophore quinones by dbmib. the sh-reagents, n-ethylmaleimide and p-chloromercurybenzoate at high concentrations inhibit membrane potential generation driven by inorganic p ...19836135455
evidence for a glutamine synthetase-chromatophore association in the phototroph rhodospirillum rubrum: purification, properties, and regulation of the enzyme.the characteristics of soluble and membrane-bound glutamine synthetase (gs) from rhodospirillum rubrum were compared with those of the enzyme located in situ (measured in detergent-treated cells). the results suggest that in vivo gs may be associated with, or bound to, the chromatophore membranes. gs was found to reversibly associate and dissociate from purified chromatophores as a function of the ionic strength of the buffer or the mg2+ concentration. solubilized gs was purified to homogeneity ...19836132914
inorganic pyrophosphate-driven atp-synthesis in liposomes containing membrane-bound inorganic pyrophosphatase and f0-f1 complex from rhodospirillum rubrum.ppi driven atp synthesis has been reconstituted in a liposomal system containing the membrane-bound energy-linked ppiase and coupling factor complex, both highly purified from rhodospirillum rubrum. this energy converting model system was made by mixing both enzyme preparations with an aqueous suspension of sonicated soybean phospholipids and subjecting to a freeze-thaw procedure. in the presence of adp, mg2+, pi and ppi the system catalyzed phosphorylation by up to 25 nmol atp formed x mg prote ...19836132837
a sensitive and rapid method for determination of pyrophosphatase activity.a new, rapid and sensitive method of measuring the rate and amount of ppi hydrolysis is described. the method is based on registration of small ph changes, caused by decrease of hydrogen-ion concentration during the pyrophosphatase reaction. with this detected value of hydrogen-ion concentration change and the buffering capacity of each reaction mixture determined by titration, the rate and amount of ppi hydrolysis can be calculated. the results obtained by ph method are in good agreement with v ...19826131564
reconstitution of highly purified proton-translocating pyrophosphatase from rhodospirillum rubrum. 19826128256
[role of inorganic pyrophosphate in the cell bioenergetics (author's transl)]. 19816121321
energy-linked reactions in photosynthetic bacteria: pi in equilibrium with hoh oxygen exchange catalyzed by the membrane-bound inorganic pyrophosphatase of rhodospirillum rubrum. 19816114711
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
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
evaluation of the complexity of charge recombination kinetics in photosynthetic bacteria. 19846095340
[delayed bacteriochlorophyll luminescence and the primary stages of electron transport in photosynthetic reaction centers of purple bacteria].the results of studies of charge separation in photosynthetic reaction centers of purple bacteria are summarized. the findings concerning the sequence of initial steps of the electron transfer and properties of the electron carriers obtained by direct methods of differential optical absorption and esr spectroscopy are compared with the data on the bacteriochlorophyll delayed fluorescence resulting from reversal of charge separation. the data analysis gives an integrated description of the reacti ...19846095028
electron-transfer reactions of photoreduced flavin analogues with c-type cytochromes: quantitation of steric and electrostatic factors.we have found correlations between rate constants and the difference in redox potential of the reactants for electron-transfer reactions between oxidized cytochromes and either photoproduced riboflavin or flavin mononucleotide (fmn) semiquinones (the latter rate constants extrapolated to infinite ionic strength). the riboflavin-cytochrome rate constants are about 70% of those for reduction by lumiflavin, probably because of steric interference by the ribityl side chain. reduction of cytochromes ...19846093864
a new crystal form and preliminary crystallographic data for ferricytochrome c' from rhodospirillum rubrum.a new crystal form of ferricytochrome c' from the photosynthetic bacteria, rhodospirillum rubrum, has been obtained by dialysing protein solution against polyethylene glycol 4000. the crystals belong to the space group p61 (or its enantiomorph p65) with unit cell dimensions: a = b = 51.63 a and c = 155.39 a. the asymmetric unit contains one dimer molecule of 28,000 molecular weight and the solvent content of the unit cell is approximately 38%.19846090675
cytochromes c' in their reaction with ethyl isocyanide.the binding of ethyl isocyanide (eic) to a representative number of cytochromes c' is demonstrated. spectroscopic and equilibrium constants have been measured and compared for the binding of eic to cytochromes c' from the photosynthetic bacteria chromatium vinosum, rhodopseudomonas palustris, rhodospirillum rubrum, and rhodopseudomonas sphaeroides. while the absorption spectra of the eic complexes resemble those of eic complexes of other high-spin hemoproteins, the soret half band widths and ext ...19846087877
influence of cyclic amp on photosynthetic development in rhodospirillum rubrum.during o2-free growth in the light and in medium with pyruvate, rhodospirillum rubrum exhibits diauxic growth. the cells first fermented pyruvate and afterwards photometabolized. exogenous cyclic amp acted to prolong the lag period between fermentative and photosynthetic development, as well as to slow the light-dependent growth rate. this observation, and in situ changes in the cyclic amp levels in cells undergoing biphasic growth, suggested that the cyclic nucleotide was involved in photosynth ...19846086589
oxido-reduction of b800-850 and b880 holochromes isolated from three species of photosynthetic bacteria as studied by electron-paramagnetic resonance and optical spectroscopy.certain redox properties of bacteriochlorophyll alpha were used to probe the structure of several light-harvesting pigment-protein complexes or holochromes. to attribute redox properties unequivocally to a given holochrome, we worked with purified holochromes. we developed purification procedures for the b880 holochromes from rhodospirillum rubrum, rhodopseudomonas sphaeroides and ectothiorhodospira sp. and for the b800-850 holochromes from the latter two species. in all these holochromes, bacte ...19846086349
new epoxyubiquinones. 19676073044
observations on the biosynthesis of phytoterpenoid quinone and chromanol nuclei.1. p-hydroxy[u-(14)c]benzoic acid, except for loss of the carboxyl group, is effectively incorporated into the nucleus of ubiquinone and an unidentified prenylphenol by maize roots, maize shoots, french-bean leaves, french-bean cotyledons and ochromonas danica. plastoquinone, alpha-tocopherol, gamma-tocopherol and alpha-tocopherolquinone are all unlabelled from this substrate. the high radioactivity of the prenylphenol and its behaviour in a pulse-labelling experiment with maize shoots suggested ...19676060446
an electrophoretic study of the heme proteins of some photosynthetic bacteria. 19676058130
ornithine-containing lipid in rhodospirillum rubrum. 19676055208
new multiprenylquinones in the biosynthesis of ubiquinone. 19676055159
the use of spectrophotometry in an ecological investigation of the facultatively anaerobic purple photosynthetic bacteria. 19676054684
carotenoid biosynthesis in rhodospirillum rubrum: effect of pteridine inhibitor.a known inhibitor of pteridine utilization (4-phenoxy,2,6-diamino pyridine) blocks the synthesis of colored carotenoids in the photosynthetic bacterium rhodospirillum rubrum. in many ways the effect is similar to the inhibition of the synthesis of colored carotenoids by diphenylamine. this inhibition is probably independent of other effects of pteridine on photosynthetic electron transport since it is not as readily reversible as the total inhibition of photosynthetic activity by pteridine analo ...19676054162
light-induced electron transfer reactions and adenosine triphosphate formation by rhodospirillum rubrum chromatophores. 19676052446
decline in bacteriochlorophyll fluorescence induced by carotenoid absorption. 19676049957
light-induced rapid absorption changes during photosynthesis. 8. cytochrome and bacteriochlorophyll reactions in rhodospirillum rubrum cells. 19676049953
identification of pteridines produced by three species of photosynthetic bacteria. 19676049523
bacilliform mutants of rhodospirillum rubrum. 19676049520
observations on the changes in ultraviolet absorbance caused by succinate and light in rhodospirillum rubrum. 19676048858
a factor from spinach leaves interacting with chlorophylls. 19676048856
pigment-protein complexes derived from rhondospirillum rubrum chromatophores by enzymatic digestion. 19676048851
photosynthesis in rhodospirillum rubrum. 3. metabolic control of reductive pentose phosphate and tricarboxylic acid cycle enzymes.enzymes of the reductive pentose phosphate cycle including ribulose-diphosphate carboxylase, ribulose-5-phosphate kinase, ribose-5-phosphate isomerase, aldolase, glyceraldehyde-3-phosphate dehydrogenase and alkaline fructose-1,6-diphos-phatase were shown to be present in autotrophically grown rhodospirillum rubrum. enzyme levels were measured in this organism grown photo- and dark heterotrophically as well. several, but not all, of these enzymes appeared to be under metabolic control, mediated b ...19676042359
photosynthesis in rhodospirillum rubrum. ii. photoheterotrophic carbon dioxide fixation.the contribution of the reductive pentose phosphate cycle to the photometabolism of carbon dioxide and to carbon metabolism in rhodospirillum rubrum grown photoheterotrophically with l-malate as the carbon source is nil, unlike autotrophically grown r. rubrum. glycolic acid appears to be the first stable product of co(2) fixation in r. rubrum cultured photoheterotrophically on l-malate. the results obtained in (14)co(2) fixation experiments suggest that the photometabolism of co(2) through glyco ...19676042358
photosynthesis in rhodospirillum rubrum. i. autotrophic carbon dioxide fixation.the incorporation and distribution of activity from (14)co(2) was investigated under autotrophic conditions in the facultative photoautotroph, rhodospirillum rubrum, with cells cultured on hydrogen, carbon dioxide, and ammonium sulfate. in 1 second (14)co(2) fixation experiments essentially all of the activity was found in 3-phosphoglyceric acid: plotted against time percent incorporation into phosphate esters has a strikingly negative slope. these results suggest that under autotrophic conditio ...19676042357
basal organelles of bacterial flagella.liberated by enzymatic lysis of the cells, the flagella of rhodospirillum rubrum, r. molischianum, and r. fulvum all have a similar structure. the hook at the base of the flagellum is connected by a short, narrow collar to a paired disc in the basal organelle. this paired disc is in turn connected to a second paired disc. the disposition of flagella to which fragments of the cell membrane still adhere suggests that the narrow collar at the base of the hook traverses both the wall and the membran ...19676039362
biosynthesis of phenylalanine from phenylacetate by chromatium and rhodospirillum rubrum.cultures of chromatium strain d and rhodospirillum rubrum incorporated (14)c from phenylacetate-1-(14)c during anaerobic growth. the radioactivity in the protein fraction of cells was mainly in phenylalanine. phenylalanine from chromatium cells grown in phenylacetate-1-(14)c was labeled at carbon 2. incorporation of phenylacetate by chromatium was decreased in the presence of exogenous phenylalanine, and de novo synthesis of phenylalanine from bicarbonate was less in medium containing either phe ...19676032506
light-induced interactions of rhodospirillum rubrum chromatophores with bromothymol blue. 19676025556
regulation of glutamine synthetase. ii. patterns of feedback inhibition in microorganisms.the feedback inhibition of glutamine synthetase was investigated by use of partially purified enzyme preparations from salmonella typhimurium, micrococcus sodonensis, pseudomonas fluorescens, bacillus cereus, bacillus licheniformis, clostridium pasteurianum, rhodospirillum rubrum, neurospora crassa, candida utilis, and chlorella pyrenoidosa. inhibition analyses indicated that the enzyme of each organism can be effectively regulated with mixtures of end products from the diverse pathways of gluta ...19676025412
isolation and characterization of glycolipids from some photosynthetic bacteria.glycosyl glycerides have been found in substantial amounts in chloropseudomonas ethylicum but could not be detected in two strains of rhodopseudomonas palustris. rhodospirillum molischianum possibly contains small amounts of monoglycosyl diglyceride. the glycolipids of c. ethylicum have been separated into two components. one of these, glycolipid i, is a monogalactosyl diglyceride. glycolipid ii, upon acid hydrolysis, yields galactose, rhamnose, and a third, unidentified sugar. the glycolipids o ...19676025299
correlation of light-induced absorbance changes with photo-phosphorylation in rhodospirillum rubrum extracts. 19676016332
spherical subunits in photosynthetic membranes of two cyanophyceae and the bacterium rhodospirillum rubrum. 19665998094
2-multiprenylphenols and 2-decaprenyl-6-methoxyphenol, biosynthetic precursors of ubiquinones. 19665980878
the light-induced, reversible ph change in chromatophores from rhodospirillum rubrum. 19665972824
purification and properties of a d(--)-beta-hydroxybutyric dimer hydrolase from rhodospirillum rubrum. 19665972339
absorption bands of bacteriochlorophyll types in purple bacteria and their response to illumination. 19665971850
effect of diqiuat (1,1'-ethylene-2,2'-dipyridylium dibromide) on the formation and photoreactions of chromatophores from rhodospirillum rubrum. 19665971848
light-induced intravesicular ph changes in rhodospirillum rubrum chromatophores. 19665971736
satellite dna in photosynthetic bacteria. 19665967242
kinetics of p-870 absorbance changes induced in rhodospirillum rubrum chromatophores by laser flashes. 19665966930
primary photosynthetic reactions in relation to transfer of excitation energy. 19665966927
the bacterial photosynthetic reaction center. 19665966926
absorption characteristics of bacteriochlorophyll types in purple bacteria and efficiency of energy transfer between them. 19665966925
the photosynthetic apparatus in chloroplasts of higher plants. 19665966916
chlorophyll-chlorophyll interactions. 19665966912
early chemical events in photosynthesis: kinetics of oxidation of cytochromes of types c or f in cells, chloroplasts, and chromatophores. 19665966902
kinetics of light-induced absorbance changes in rhodospirillum rubrum extracts. 19665961081
Displaying items 1101 - 1200 of 2252