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complete stabilization of water-soluble hydrogenase from rhodospirillum rubrum under air atmosphere with a high concentration of chloride ions.hydrogenase was easily solubilized from light-grown cells of r. rubrum with 10 mm na ethylenediaminetetraacetate. the enzyme thus obtained was so stable that loss of its activity was undetectable during storage at room temperature for 6 months under air atmosphere, provided that nacl, kcl or cscl was present at greater than or equal to 0.7 m.1978104983
a kinetic study of ribulose bisphosphate carboxylase from the photosynthetic bacterium rhodospirillum rubrum.the activation kinetics of purified rhodospirillum rubrum ribulose bisphosphate carboxylase were analysed. the equilibrium constant for activation by co(2) was 600 micron and that for activation by mg2+ was 90 micron, and the second-order activation constant for the reaction of co(2) with inactive enzyme (k+1) was 0.25 x 10(-3)min-1 . micron-1. the latter value was considerably lower than the k+1 for higher-plant enzyme (7 x 10(-3)-10 x 10(-3)min-1 . micron-1). 6-phosphogluconate had little effe ...1978100101
properties of the nitrogenase system from a photosynthetic bacterium, rhodospirillum rubrum.soluble nitrogenase from rhodospirillum rubrum has been isolated and separated into its two components, the mofe protein and the fe protein. the mofe protein has been purified to near homogeneity and has a molecular weight or 215 000. it contains two mo, 25--30 fe and 19--22 acid-labile sulphide and consists of four subunits, mw 56 000. the fe protein has a molecular weight 65 000. it contains approximately four fe and four acid-labile sulphide and consists of two subunits, mw 31 500. the highes ...1978102339
inhibition of energy conservation reactions in chromatophores of rhodospirillum rubrum by antibiotics. 1978147053
the interactions of coupling atpases with nucleotides. 1978147104
nitrogen electron nuclear double resonance and proton triple resonance experiments on the bacteriochlorophyll cation in solution.electron nuclear double resonance signals of the pyrrole nitrogens of bacteriochlorophyll alpha cation in a solution of ch2cl2/ch3oh (6:1) have been observed. the nitrogens are inequivalent: the hyperfine coupling constants were determined to be 2.36 and 3.18 mhz (0.84 and 1.14 g, respectively). triple electron nuclear double resonance experiments have yielded the signs and values of nine proton hyperfine coupling constants. the assignment based on these data agrees well with previous work (borg ...197897667
dichroism of bacteriochlorophyll in chromatophores of photosynthetic bacteria.the dichroism was measured in films of air-dried and, consequently, flattened chromatophores of chromatium vinosum, rhodopseudomonas sphaeroides and rhodospirillum rubrum. the values (deltaa/a) of dichroism in c. vinosum were found to be -1.05 at 590 nm and 0.75 in the near infrared region. the values of dichroism in r. sphaeroides were -0.70 at 590 nm and 0.80 at 870 nm. the values of dichroism in r. rubrum were -1.45 at 590 nm and 0.97 at 870 nm.197897281
isolation of a membrane protein from r rubrum chromatophores and its abnormal behavior in sds-polyacrylamide gel electrophoresis due to a high binding capacity for sds.a membrane protein insoluble in water was isolated by gel chromatography in the presence of 0.1% sodium dodecyl sulfate (sds) from chromatophores of a photosynthetic bacterium, rhodospirillum rubrum. this is one of the major membrane proteins of the chromatophore. the protein was found to bind about four grams of sds per gram, a value which is more than twice the amount generally observed with protein polypeptides derived from water-soluble globular proteins. the electrophoretic behavior of the ...197897280
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 ...197896875
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 ...197896854
affinity chromatography of h+-translocating adenosine triphosphatase isolated by chloroform extraction of rhodospirillum rubrum chromatophores. modification of binding affinity by divalent cations and activating anions.1. atpase isolated from rhodospirillum rubrum by chloroform extraction and purified by gel filtration or affinity chromatography shows three bands (alpha, beta and gamma) upon electrophoresis in sodium dodecyl sulphate. 2. ca2+-atpase activity of the preparation is inhibited by aurovertin and efrapeptin but not by oligomycin. activity may be inhibited by treatment with 4-chloro-7-nitrobenzofurazan and subsequently restored by dithiothreitol. 3. the enzyme fails to reconstitute photophosphorylati ...197827212
modification of rhodospirillum rubrum ribulose bisphosphate carboxylase with pyridoxal phosphate. 1. identification of a lysyl residue at the active site.ribulose 1,5-bisphosphate carboxylase isolated from rhodospirillum rubrum was strongly inhibited by low concentrations of pyridoxal 5'-phosphate. activity was protected by the substrate ribulose bisphosphate and to a lesser extent by other phosphorylated compounds. pyridoxal phosphate inhibition was enhanced in the presence of magnesium and bicarbonate, but not in the presence of either compound alone. concomitant with inhibition of enzyme activity, pyridoxal phosphate forms a schiff base with t ...197826381
the preparation and characterization of different types of light-harvesting pigment-protein complexes from some purple bacteria.a general strategy, with some specific examples, is given for the isolation and purification of detergent-soluble, antenna pigment-protein complexes from the photosynthetic membranes. absorption, fluorescence and circular dichroism spectra, and the pigment and protein composition of b800-b850-protein and b890-protein complexes of some purple bacteria (rhodospirillum rubrum, rhodopseudomonas sphaeroides and rps. capsulata and chromatium vinosum) are discussed. we conclude that there are probably ...1978110568
ribulose bisphosphate carboxylases from chromatium vinosum and rhodospirillum rubrum and their role in photosynthetic carbon assimilation. 1978106836
ribulose 1,5-bisphosphate carboxylase from autotrophic micro-organisms [proceedings]. 1978105954
pyruvate fermentation in light-grown cells of rhodospirillum rubrum during adaptation to anaerobic dark conditions.pyruvate fermentation in rhodospirillum rubrum (strains f1, s1, and ha) was investigated using cells precultured on different substrates anaerobically in the light and than transferred to anaerobic dark conditions. pyruvate formate lyase was always the key enzyme in pyruvate fermentation but its activity was lower than in cells which have been precultured aerobically in darkness. the preculture substrate also had a clear influence on the pyruvate formate lyase activity. strains f1 and s1 metabol ...1978103509
purification and properties of nitrogenase from rhodospirillum rubrum, and evidence for phosphate, ribose and an adenine-like unit covalently bound to the iron protein.1. the molybdenum-iron (mo-fe) protein, iron (fe) protein and the activating factor of nitrogenase from rhodospirillum rubrum were purified. 2. the mo-fe protein has properties similar to those of the mo-fe proteins of other nitrogen-fixing organisms. 3. the fe protein is similar to other fe proteins with respect to its molecular weight, metal composition and e.p.r. signal. 4. the fe protein is different from other fe proteins in that it apparently has two types of subunits rather than one, its ...1978104713
viability and endogenous substrates used during starvation survival of rhodospirillum rubrum.cells of rhodospirillum rubrum were grown photoorganotrophically and chemoorganotrophically and then starved for organic carbon and combined nitrogen under four conditions: anaerobically in the light and dark and aerobically in the light and dark. illumination prolonged viability and suppressed the net degradation of cell material of phototrophically grown cells, but had no effect on chemotrophically grown cells that did not contain bacteriochlorophyll. the half-life survival times of carbohydra ...197896087
studies on regulatory functions of malic enzymes. v. comparative studies of malic enzymes in bacteria.screening of four malic enzymes--nad-linked enzyme [ec 1.1.1.38], nad, nadp-linked enzyme [ec 1.1.1.39], nadp-linked enzyme [ec 1.1.1.40], and d-malic enzyme--was carried out with cell-free extracts of the following 16 strains of bacteria by the aid of sepharose 6b column chromatography: 9 strains of enteric bacteria, 3 strains of pseudomonas, alcaligenes faecalis, agrobacterium tumefaciens, rhodospirillum rubrum, and clostridium tetanomorphum. all the strains tested contained at least one malic ...197896110
picosecond detection of bchl-800 as an intermediate electron carrier between selectively-excited p870 and bacteriopheophytin in rhodospirillum rubrum relaction centers. 197897097
[picosecond energy transfer between the spectral forms of pigments from the reaction center of rhodospirillum rubrum].absorption changes of reaction centers from rhodospirillum rubrum at 748, 796 and 870 nm induced by 532 and 870 nm picosecond light pulses were investigated with a picosecond spectrometer. kinetics of absorption changes at 748 and 796 had an additional bleaching when induced by the 532 nm pulse, in comparison with those at 870 nm. the additional bleaching was interpreted as a result of the excitation energy transfer via spectral forms of pigments of reaction centers. the experimental results fit ...1978100143
retention of the oxygens at c-2 and c-3 of d-ribulose 1,5-bisphosphate in the reaction catalyzed by ribulose-1,5-bisphosphate carboxylase.ribulose-1,5-bisphosphate carboxylase catalyzes the conversion of d ribulose 1,5-bisphosphate and co2 to 3-phospho-d-glycerate, with retention of the oxygen atoms at both c-2 and c-3 of the substrate. this observation is consistent with mechanistic pathways involving an enediol intermediate and eliminates suggested mechanisms that involve covalent intermediates between the enzyme and ribulose 1,5-bisphosphate in which the substrate oxygen at c-2 or c-3 is compulsorily lost.1978101236
preparation of nitrogenase. 1978101737
involvement of an essential arginyl residue in the coupling activity of rhodospirillum rubrum chromatophores. 1978102254
resolution and reconstitution of rhodospirillum rubrum pyridine dinucleotide transhydrogenase: localization of substrate binding sites. 1978102261
energy-liked reactions in photosynthetic bacteria. x. solubilization of the membrane-bound energy-linked inorganic pyrophosphatase of rhodospirillum rubrum. 1978102323
the proton pump is a molecular engine of motile bacteria. 197824186
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 ...197826430
pms photo-inhibition in rhodospirillum rubrum membranes in the presence of permeant entities affecting either the deltapsi or the deltaph components of the protonmotive force. 197829789
reversible conversion from ca(2)+-atpase activity to mg(2)+- and mn(2)+-atpase activities of coupling factor purified from acetone powder of rhodospirillum rubrum chromatophores.it is known that the coupling factor purified from the acetone powder of chromatophores from rhodospirillum rubrum shows atpase activity in the presence of ca(2)+, but not in the presence of mg(2)+ or mn(2)+. the present study deals with conditions, under which the ca(2)+-atpase activity is reversibly converted into mg(2)+- and mn(2)+-atpase activites with the purified coupling factor. 1. of the ph indicators tested, 6 kinds coverted the ca(2)+-atpase activity into mg(2)+- and mn(2)+-atpase acti ...197830771
dna-dependent rna and polyadenylic acid polymerase from phototrophically grown rhodospirillum rubrum.dna-dependent rna and polyadenylic acid polymerases have been purified from phototrophic rhodospirillum rubrum. their properties have been found to be very similar to those of the previously reported heterotrophic r. rubrum enzymes. however, several important differences do exist between the enzymes from the phototrophic and the heterotrophic cells, such as the lack of response to added polyadenylic acid for poly a synthesis and the presence of the sigma subunit in the phototrophic enzymes. fur ...197831974
distribution of adenosine 5'-triphosphate (atp)-dependent hexose kinases in microorganisms.a systematic study of adenosine triphosphate (atp)-dependent hexose kinases among microorganisms has been undertaken. sixteen hexose kinases of five major types were partially purified from 12 microorganisms and characterized with respect to specificity for sugar and nucleotide substrates and michaelis constants for the sugar substrates. glucokinase activities that phosphorylate glucose and glucosamine are inhibited by n-acetyl-glucosamine and xylose, were found to be present in the non-sulphur ...1978214181
direct measurement of pure absorbance spectra of living phototrophic microorganisms.the pure absorbance of turbid cell suspensions of various phototrophic microorganisms were determined by collecting the scattered light. a conventional spectrophotometer was used, equipped with an intergrating sphere as receiver unit, which allowed precise measurements of the absorbance in the range from zero to 0.1. in the wavelength range 300--1100 nm, where photosynthesis occurs, light scattered only once by a bacterial cell retains predominantly the forward direction. this allows measurement ...1978626755
quantum yield and image contrast of bacteriochlorophyll monolayers in photoelectron microscopy.the photoelectron quantum yield spectrum of bacteriochlorophyll agg (bchl a ) from rhodospirillum rubrum was determined in order to evaluate the possibility of mapping photoreceptor distribution and organization in bacterial chromatophores. the quantum yield is on the order of 1 x 10(-3) electrons/incident photon at 180 nm and decreases to 2.5 x 10(-5) electrons/incident photon at 230 nm. photoelectron micrographs confirm the high contrast predicted between monolayers of bchl a against a lipid b ...1978630040
structural studies on the d-arabinose-containing lipid a from rhodospirillum tenue 2761.structural studies carried out on the isolated free lipid a of rhodospirillum tenue 2761 revealed a new type of structure for this lipid. the lipid a backbone of 1',6-linked glucosamine disaccharide (central disaccharide) is substituted by three different sugar residues: the non-reducing end of the disaccharide by 4-amino-4-deoxy-l-arabinose 1-phosphate and its reducing end glycosidically by d-arabinofuranose 1-phosphate; further, the reducing glucosamine of the disaccharide is branched to a thi ...1978639795
purification of (4fe-4s)1--2--ferredoxins (high-potential iron--sulfur proteins) from bacteria. 1978713842
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. ...1978214418
immunogenicity of methyl esters of nocardomycolic acids.immunogenicity of methyl esters of fatty acids of nocardiae (nocardia (nocardia asteroides atcc 19247, n, brasiliensis n318 and n. caviae n231) was studied. the rabbit antisera obtained against the lipid fractions reacted in the complement fixation test (cf) and in the pash sive cutaneous anaphylaxis test (pca). the results of absorption experiments witt separated fractions of fatty acids esters indicate that the antisera showed activity againsmethyl esters of nocardomycolic acids.1978749777
dna homology studies on nocardia and rhodococcus strains.the genetic homogeneity of nocardia amarae, nocardia autotrophica and rhodococcus strains and the relationship among these groups of microorganisms have been studied using the dna reassociation method. strains belonging to n. amarae and n. autotrophica form genetically homogeneous groups. distinct differences have been found out among rhodococcus strains.1978749779
[relation of cyclic and noncyclic electron transport in rhodospirillum rubrum chromatophores. i. experimental study of the kinetic characteristics of dark reduction of p870 with different donor concentrations in the medium].the kinetics of the dark recovery of photo-oxidized bacteriochlorophyll p870 was studied as a function of the intensity and duration of actinic light illumination at different concentrations of a donor in the medium. from the comparison of the experimental data with the results of mathematical modelling of the processes under investigation [1] it is concluded that electron transport is triggered for another pathway, whenever the concentration of the donor in the medium attains a certain critical ...1978414786
continuous monitoring of the electrical potential across energy-transducing membranes using ion-selective electrodes. application to submitochondrial particles and chromatophores. 1978414935
measurement by a flow dialysis technique of the steady-state proton-motive force in chromatophores from rhodospirillum rubrum. comparison with phosphorylation potential.1. in the light a transmembrane electrical potential of 100 mv has been estimated to occur in chromatophores from rhodospirillum rubrum. the potential was determined by measuring the steady-state distribution of the permeant scn- across the chromatophore membrane using a flow dialysis technique. the potential was not observed in the dark, nor in the presence of antimycin. it was dissipated on the addition of carbonyl cyanide p-trifluoromethoxyphenylhydrazone. the potential was reduced by between ...1978416847
bacteriochlorophyll-protein complexes from the light-harvesting antenna of photosynthetic bacteria. 1978418797
mössbauer study of cytochrome c2 from rhodospirillum rubrum. sign of the product gxgygz of some low spin ferric heme proteins.we have studied cytochrome c2 from rhodospirllum rubrum with mössbauer spectroscopy and electron paramagnetic resonance. the mössbauer data on the ferric protein, taken in external magnetic fields up to 50 kg, were analyzed within the framework of the ligand field model commonly used to evaluate low-spin ferric heme compounds. the data analysis shows that the determinant of the electronic g-tensor, i.e. the product gxgygz, is positive for cytochrome c2. we have reanalyzed published mössbauer dat ...1978208633
the photoproduction of h2 and nh4 fixed from n2 by a derepressed mutant of rhodospirillum rubrum.a mutant of rhodospirillum rubrum has been isolated, after mutagenesis with nitrosoguanidine, which is characterized by its inability to grow in the light on malate-minimal media with exogenous ammonia or alanine, poor growth on glutamine and vigorous growth on glutamate. this mutant produces low levels of a key nh+4 assimilation enzyme, glutamate synthase (nadph-dependent). it also exhibits significant derepression of nitrogenase biosynthesis in the presence of ammonia or alanine, being 15% der ...1978418808
proteins exposed at the surface of chromatophores of rhodospirillum rubrum: the orientation of isolated chromatophores.the exposure of proteins at the surface of isolated chromatophores (i.e., the cytoplasmic face of intracytoplasmic membranes) of rhodospirillum rubrum was studied by proteolysis as well as by enzymatic iodination with 125i. analyses were performed after polyacrylamide gel electrophoresis of chromatophore proteins solubilized with sodium dodecyl sulfate. reversible light induced proton uptake by partially digested chromatophores was used as a criterion for the integrity of the permeability barrie ...1978418810
flash-induced photophosphorylation in rhodospirillum rubrum chromatophores. i. the relationship between cytochrome c-420 content and photophosphorylation.the content of cytochrome c-420 in rhodospirillum rubrum chromatophores prepared by grinding with alumina is 5--10% of that in whole cells, and 20--40% in chromatophores by 'french' pressing. flash-induced phosphorylation of various chromatophores which varied in cytochrome content from 7 to 40% is proportional to the cytochrome content. extrapolating the cytochrome c-420 content to that observed in whole cells, a ratio atp/p+x- near 1 is calculated. at low flash intensity the phosphorylation pe ...1978213110
regulation of adenosine diphosphate glucose pyrophosphorylase. 1978345767
electron spin polarization in photosynthesis and the mechanism of electron transfer in photosystem i. experimental observations.transient electron paramagnetic resonance (epr) methods are used to examine the spin populations of the light-induced radicals produced in spinach chloroplasts, photosystem i particles, and chlorella pyrenoidosa. we observe both emission and enhanced absorption within the hyperfine structure of the epr spectrum of p700+, the photooxidized reaction-center chlorophyll radical (signal i). by using flow gradients or magnetic fields to orient the chloroplasts in the zeeman field, we are able to influ ...1978204369
electron spin resonance in zero magnetic field of the reaction center triplet of photosynthetic bacteria.the decay rates kx, ky, kz of the individual spin levels of the light-induced triplet state have been accurately measured by the zero-field resonance technique under conditions of very low light intensity and a microwave sweep rate of 2.5 mhz/microseconds, which is in excess of that commonly used in optical detection magnetic resonance experiments. the rates ku found correspond well with those previously determined under somewhat different conditions (hoff, a.j. (1976) biochim. biophys. acta 440 ...1978208604
relationships in hydrogen metabolism between hydrogenase and nitrogenase in phototrophic bacteria.purple bacteria rhodospirillum rubrum and thiocapsa roseopersicina form two enzymes, hydrogenase and nitrogenase, which participate in hydrogen metabolism. h2 photoproduction in these bacteria is associated mainly or completely with the action of nitrogenase. the soluble and membrane-bound hydrogenases of t. roseopersicina have similar physicochemical properties (mol. weight, subunit composition, n-terminal amino acids, fe2+ and s2- content, pl. eo'). in comparison with other hydrogenases the en ...1978208659
on the significance of electron transport systems for growth of rhodospirillum rubrum. 1978211972
on the state of carotenoids bound to reaction centers of photosynthetic bacteria: a resonance raman study.the carotenoids bound to reaction centers of wild, ga and gic strains of rhodopseudomonas spheroides, of rhodospirrillum rubrum, strain s1 and of rhodopseudomonas viridis, yield very similar, but unusual resonance raman spectra. through a comparison with resonance raman spectra of 15,15'-cis-beta-carotene, these carotenoids are shown to assume cis conformations, while the corresponding chromatophores contain all-trans forms only. these cis conformations likely are identical for all the carotenoi ...197899169
facile assay of enzymes unique to the calvin cycle in intact cells, with special reference to ribulose 1,5-bisphosphate carboxylase. 1978204219
inactivation of ribulosebisphosphate carboxylase by modification of arginyl residues with phenylglyoxal.phenylglyoxal rapidly and completely inactivates spinach and rhodospirillum rubrum ribulosebisphosphate carboxylases. inactivation exhibits pseudo-first-order kinetics and a reaction order of approximately one for both enzymes, suggesting that modification of a single residue per protomeric unit suffices for inactivation. loss of enzymic activity is directly proportional to incorporation of [14c]phenylglyoxal until only 30% of the initial activity remains. for both enzymes, extrapolation of inco ...1978728421
structure and function of photoreaction-centre chlorophyll.evidence from electron paramagnetic resonance (e.p.r.) studies suggests that the unpaired spin in oxidized p700+. or p865+. is shared by two special chlorophyll a (chl a) or bacteriochlorophyll a (bchl a) molecules respectively. three classes of models have been proposed for special pair reaction centre chlorophyll: asymmetric, in which one chl a (or bchl a) acts as electron donor to a second acting as acceptor; models with translational symmetry only; and models with c2 symmetry. models with c2 ...1978222557
modification of rhodospirillum rubrum ribulose bisphosphate carboxylase with pyridoxal phosphate. 2. stoichiometry and kinetics of inactivation.rhodospirillum rubrum ribulose bisphosphate carboxylase contains two high affinity binding sites for pyridoxal phosphate and two catalytic sites per dimer. however, pyridoxal phosphate binding at only one site is sufficient for inactivation of both catalytic sites. in the presence of 20 mm bicarbonate, 10 mm magnesium, and pyridoxal phosphate, the rates of inactivation and schiff base formation are pseudo-first-order and show saturation kinetics. these observations provide additional evidence th ...1978418800
a comparison of electron transport and photophosphorylation systems of rhodopseudomonas capsulata and rhodospirillum rubrum. effects of antimycin a and dibromothymoquinone.the photophosphorylation systems of rhodopseudomonas capsulata and rhodospirillum rubrum chromatophores have been compared in respect to the effects of artificial electron carriers [n-methylphenazonium methosulfate (pms) and diaminodurene], reducing agents (ascorbate in particular), and various quinones in the absence and presence of the electron transport inhibitors antimycin a and dibromothymoquinone (dbmib). in addition, the effects of both inhibitors on photosynthetic electron transport thro ...1978414685
homoserine dehydrogenase of rhodospirillum rubrum. physical and chemical characterization.a detailed physicochemical characterization of purified homoserine dehydrogenase of rhodospirillum rubrum is presented. the enzyme has a molecular weight of 110000 and consists of two subunits of identical molecular weight of 55000. depending on the ionic strength and protein concentration it is possible for the native enzyme to dimerize to produce an enzymatically active species of molecular weight 220000. titrations of the native and detergent-treated enzyme with a variety of sulfhydryl reagen ...1978414912
biochemical identification of a tryptophan auxotroph in rhodospirillum rubrum.a tryptophan auxotroph of aerobically grown rodospirillum rubrum was isolated after mutagenesis and replica plating. the mutant grows on tryptophan or indole, accumulates indole glycerol phosphate, lacks the capacity to convert indole glycerol phosphate to indole glycerol phosphate to indole, and finally is defective in photosynthetic growth. the strain is, therefore, analogous to a trp a mutant which is defective in the alpha-subunit structural gene of tryptophan synthetase.1978417790
[intermediate states formed during discharge separation in the reaction centers of rhodospirillum rubrum in the presence of a low-redox potential].the intermediate short-lived states arising in reaction centre preparations (rc) of purple bacterium rhodospirillum rubrum are investigated under the conditions of low redox potential. excitation by 353 and 530 nm laser pulses produced two states characterized by optical absorption changes in the range of 350--650 nm and lifetimes: 10--30 ns for the first state and 2.5 +/- 0.5 microseconds for the second one. the first state is similar to the state pf, described previously by parson et al. for r ...1978418326
homoserine dehydrogenase: spontaneous reactivation by dissociation of p-mercuribenzoate from an inactive enzyme--p-mercuribenzoate complex.incubation of rhodospirillum rubrum homoserine dehydrogenase (l-homoserine:nad+ oxidoreductase, ec 1.1.1.3) with p-mercuribenzoate (pmb) in the presence of 0.2 m kcl and 2 mm l-threonine resulted in complete loss of enzyme activity. upon removal of excess pmb, kcl, and l-threonine, a time-dependent recovery of enzyme activity was observed in 25 mm phosphate/i mm edta buffer, ph 7.5. circular dichroism studies indicated that the transition from inactive to reactivated form of the enzyme was accom ...1977270718
isolation and characterization of an organic solvent soluble polypeptide component from photoreceptor complexes of rhodospirillum rubrum.an organic solvent soluble polypeptide has been isolated from photoreceptor complexes and chromatophores of rhodospirillum rubrum. after extraction of the protein from lyophilized samples with 1:1 chloroform-methanol, it was purified by column chromatography. its isoelectric point determined by isoelectric focusing was 7.10. when analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the purified polypeptide ran as a single band of an apparent molecular weight of 12 000. however, ...1977402930
ubiquinone and photochemical activity in rhodospirillum rubrum. 1977403533
mechanisms of co2 fixation in bacterial photosynthesis studied by the carbon isotope fractionation technique.the carbon isotope discrimination properties of a representative of each of the three types of photosynthetic bacteria chlorobium thiosulfatophilum, rhodospirillum rubrum and chromatium and of the c3-alga chlamydomonas reinhardii were determined by measuring the ratio of 13co2 to 12co2 incorporated during photoautotrophic growth. 2. chromatium and r. rubrum had isotope selection properties similar to those of c3-plants, whereas chlorobium was significantly different. 3. the results suggest that ...1977402896
evidence for monomeric bacteriochlorophyll in p800 of the photoreaction center from rhodospirillum rubrum.to find out whether weak or strong coupling exists between the bacteriochlorophyll molecules of the photoreaction center, the relative efficiency of energy transfer to p870 was measured at 795 nm and at 808 nm, at room temperature and at 77 degrees k. at room temperature, both relative efficiencies are close to 100%. however, at 77 degrees k, 795 nm light has a quantum efficiency of 76% and 808 nm light has an efficiency of 87%. these results confirm the fact that p800 is formed of at least one ...1977403944
the effect of electron donors and acceptors on light-induced absorbance changes and photophosphorylation in rhodospirillum rubrum chromatophores.light-induced difference spectra between 400 and 640 nm of rhodospirillum rubrum chromatophores were performed in the presence and absence of exogenous electron donor/acceptor systems and compared with the chemical oxidation spectrum. the results indicate that the component previously defined as p430 is not a unique entity but rather represents different species, or a mixture of species, under various conditions. under all conditions in which the reaction center bacteriochlorophyll is reversibly ...1977411652
[light-induced oxygen uptake by chromatophores and subchromatophore pigment-protein complexes of rhodospirillum rubrum].chromatophores of r. rubrum incubated with electron donors, e. g. reduced diaminodurene, tmpd, phenazine methosulphate, cytochrome c or ferrocyanide, are able to catalyze o2 uptake upon illumination. this process is inhibited by o-phenanthroline as well as upon extraction of quinones from chromatophores, but not by antimycin a, rotenone or cn-. the o2 uptake sensitive to the action of o-phenanthroline is also observed in the illuminated subchromatophore p870 reaction center complexes and reactio ...1977412525
comparison of the electrochemical proton gradient and phosphate potential maintained by rhodospirillum rubrum chromatophores in the steady state. 1977402116
isolation of an iron-molybdenum cofactor from nitrogenase.a method for the isolation of an iron-molybdenum cofactor (femoco) from component i of nitrogenase is described. this method is used to isolate femoco from aerobic, anaerobic, facultative, and photosynthetic nitrogen-fixing organisms. the fe/mo ratio in the femoco from azotobacter vinelandii and clostridium pasteurianum is 8:1. the femoco contains six atoms of acid-labile sulfide per eight fe atoms. crystalline component i from a. vinelandii contains 2 mo, 33 fe, and 27 acid-labile sulfide atoms ...1977410019
localisation of the subunits of the photosynthetic reaction centers in the chromatophore membrane of rhodospirillum rubrum.reaction centers were isolated with the detergent lauryl dimethyl amine oxide from chromatophore membranes of rhodospirillum rubrum. the subunit composition of these reaction centers is similar to the one obtained from rhodopseudomonas spheroides: three subunits with the molecular weights of 21 000, 24 000 and 29 000. reaction centers prepared from chromatophores labeled with 131i were heavely labeled in their large subunit (h). the smaller subunits (l and m) contained only little label. sonicat ...1977403945
reaction of ribulosebisphosphate carboxylase from rhodospirlilum rubrum with the potential affinity label 3-bromo-1,4-dihydroxy-2-butanone 1,4-biphosphate. 1977403917
near-infrared magnetic circular dichroism of cytochrome c'.the near-infrared magnetic circular dichroism (mcd) of rhodospirillum rubrum, chromatium vinosum, and rhodopseudomonas palustris cytochromes c' are reported. the spectra of the reduced protein are very similar to those of deoxymyoglobin. the spectra of the oxidized proteins in the pd range 1-13 can be analyzed on the basis of four species a, b, c, and d. the existence of nine species, reported in a recent electron paramagnetic resonance study, is not substantiated. the mcd spectra support the as ...1977192272
amino acid sequence of desulfovibrio vulgaris flavodoxin.the complete amino acid sequence for the 148-amino acid flavodoxin from desulfovibrio vulgaris was determined to be: h3n+-met-pro-lys-ala-leu-ile-val-tyr-gly-ser-thr-thr-gly-asn-thr-glu-tyr-thr-ala-glu-thr-ile-ala-arg-glu-leu-ala-asn-ala-gly-tyr-glu-val-asp-ser-arg-asp-ala-ala-ser-val-glu-ala-gly-gly-leu-phe-glu-gly-phe-asp-leu-val-leu-leu-gly-cys-ser-thr-trp-gly-asp-asp-ser-ile-glu-leu-gln-asp-asp-phe-ile-pro-leu-phe-asp-ser-leu-glu-glu-thr-gly-ala-gln-gly-arg-lys-val-ala-cys-phe-gly-cys-gly-as ...1977402366
stereochemistry of the porphyrin-protein bond of cytochrome c. stereochemical comparison of rhodospirillum rubrum, yeast, and horse heart porphyrins c.porphyrins c have been obtained from rhodospirillum rubrum cytochrome c2, yeast cytochrome c, and horse heart cytochrome c and compared using proton magnetic resonance and circular dichroism. identity of the spectra establishes that chemically and stereochemically the three porphyrins c are identical. since the stereochemistry of the porphyrin alpha-thioether linkage is not affected in the conversion to porphyrin c, the stereochemistry at the porphyrin alpha-thioether bonds among the correspondi ...1977192273
effects of long-term treatment with acetylene on nitrogen-fixing microorganisms.long periods of experimental incubation with acetylene led to a multifold enhancement of acetylene-reducing activity in anabaena cylindrica, anabaenopsis circularis, rhodospirillum rubrum, and azotobacter vinelandii. rates of acetylene reduction showed a gradual increase and reached a peak after 2 to 6 h of continuous incubation under acetylene. thereafter, enzyme activity rapidly declined. a similar enhancement of ethylene production was observed when pretreatment with acetylene was interrupted ...1977413480
necessity of a membrane component for nitrogenase activity in rhodospirillum rubrum.acetylene reduction catalyzed by nitrogenase from rhodospirillum rubrum has low activity and exhibits a lag phase. the activity can be increased by the addition of a chromatophore membrane component and the lag eliminated by preincubation with this component, which can be solubilized from chromatophores by treatment with nacl. it is both trypsin- and oxygen-sensitive. titration of the membrane component with nitrogenase and vice versa shows a saturation point. the membrane component interacts sp ...1977410446
structural aspects of the reaction center of photosynthetic bacteria calculated from triplet state zero-field splittings. 1977410658
excitation trapping by different states of photosynthetic reaction centres. 1977410664
demonstration of two 3,3'-diaminobenzidine oxidation reactions associated with photosynthetic membranes in anaerobic light-grown rhodospirillum rubrum.photosynthetic membranes of anaerobic light-grown rhodospirillum rubrum oxidized 3,3'-diaminobenzidine. when glutaraldehyde-treated cells were exposed to 3,3'-diaminobenzidine in the light aerobically, the oxidation appeared to occur by two systems. one reaction was stimulated by white light and the second required molecular oxygen. the o2-dependent activity was inhibited by kcn.1977410873
physiological studies of spirillum lipoferum. 1977411476
linear dichroism of light-induced absorbance changes of reaction centers of rhodospirillum rubrum. 1977405251
a novel pathway for l-citramalate synthesis in rhodospirillum rubrum.when [14c]propionate was incubated with a cell-free extract of rhodospirillum rubrum in the presence of glyoxylate, atp, coa, mg2+, and mn2+, radioactivity was incorporated into mesaconate (msa) as well as into beta-methylmalate (mma) and citramalate (cma). msa was suggested to be an intermediate of the conversion of mma to cma based on the following observations. (i) when non-labeled msa was added to the cma-forming reaction system, radioactivity was trapped in msa. (ii) when msa was incubated ...1977405381
simple equipment for the growth of photosynthetic bacteria. 1977406256
purification, molecular properties, and amino acid composition of the subunits of rhodospirillum rubrum succinate dehydrogenase. 1977406851
reduction of adenylylsulfate and 3'-phosphoadenylylsulfate in phototrophic bacteria.extracts of 14 species of phototrophic bacteria, partly grown with different sulfur compounds, were tested for their ability to form volatile sulfur compounds from adenylylsulfate (aps) and 3'-phosphoadenylylsulfate (paps). the rhodospirillum species showed marked activities with both aps and paps while the rhodopseudomonas species seem to prefer paps. the chromatiaceae exhibited the strongest activities with aps, whereas chlorobium limicola had equally high activity with paps.1977408177
sensitive measurement of flash induced photophosphorylation in bacterial chromatophores by firefly luciferase. 1977408188
isolation and characterization of a bacteriochlorophyll-associated chromatophore protein from rhodospirillum rubrum g-9. 1977408189
[carbonic anhydrase activity of phototropic bacteria].the activity of carboanhydrase was assayed in seven species of phototrophous bacteria: three species of the rhodospirillaceae genus, three species of the chromatiaceae genus, and one species of the chlorobiaceae genus. the activity of carboanhydrase was found in five species among seven. it decreased on passing from photoautotrophous to photoheterotrophous conditions of growth, and then to dark heterotrophous conditions, which correlated with the activity of the calvin cycle in the bacteria. no ...1977408582
isolation of a photosynthetic strain of rhodospirillum rubrum with an altered reaction center. 1977409348
isolation of the membrane-bound hydrogenase from rhodospirillum rubrum. 1977409403
structure and function of carotenoids in the photoreaction center from rhodospirillum rebrum. 1977409431
energy-linked nicotinamide nucleotide transhydrogenases. 1977409434
biological activities of lipopolysaccharides and lipid a from rhodospirillaceae.the lipopolysaccharides and free lipid a from several strains of rhodospirillaceae were assayed comparatively with those of enterobacteriaceae in a number of biological tests. free lipid a's from rhodopseudomonas gelatinosa and rhodospirillum tenue exhibited strong serological cross-reactions with each other and with free lipid a from salmonella. lipid a's from rhodopseudomonas viridis and rhodopseudomonas palustris, although cross-reacting with each other, did not do so with either the lipid a ...1977558961
preliminary crystallographic data for cytochromes c' of rhodopseudomonas capsulata and rhodospirillum molischianum. 1977204789
interconversion of two kinetically distinct states of the membrane-bound and solubilised h+-translocating atpase from rhodospirillum rubrum. 197715868
adenosine-5'-phosphosulfate (aps) as sulfate donor for assimilatory sulfate reduction in rhodospirillum rubrum.crude extracts of rhodospirillum rubrum catalyzed the formation of acid-volatile radioactivity from (35s) sulfate, (35s) adenosine-5'-phosphosulfate, and (35s) 3'-phosphoadenosine-5'-phosphosulfate. an enzyme fraction similar to aps-sulfotransferases from plant sources was purified 228-fold from rhodospirillum rubrum. it is suggested here that this enzyme is specific for adenosine-5'-phosphosulfate, because the purified enzyme fraction metabolized adenosine-5'-phosphosulfate; 3'-phosphoadenosine ...197716577
multiple forms of dna-dependent rna and polyadenylic acid polymerases from heterotrophically grown rhodospirillum rubrum.three, two major and one minor, distinct rna polymerases have been isolated and partially purified from heterotrophically grown rhodospirillum rubrum, a facultative photosynethetic bacterium. associated with each of these three enzymes is a distinct polyadenylic acid polyemrase. all of these enzyme activities are dependent on dna templates and are resistant to rifampicin and streptovaricin. the structural subunit composition, the response to various chemical compounds and dna templates, and the ...197717456
fermentative metabolism of pyruvate by rhodospirillum rubrum after anaerobic growth in darkness.rhodospirillum rubrum grew anaerobically in darkness and fermented sodium pyruvate by a pyruvate formate-lyase reaction. during 30 min of anaerobic dark or light incubation with sodium pyrivate, crude extracts from fermentatively grown cells produced about 6 micronmol of acetylphosphate and formate per mg of protein in reactions performed at ph 8.3. cell extracts also catalyzed the exchange of sodium 14cformate into sodium pyruvate at an apparent ph optimum of 7.3 to 7.5, but only about 2.5 micr ...197718439
resonance raman study of the ph-dependent and detergent-induced structural alterations in the heme moiety of rhodospirillum rubrum cytochrome c'.the resonance raman spectra and the structures of the heme moiety of rhodospirillum rubrum cytochrome c' were investigated for its five states characterized by absorption spectra; types-a and -n of the reduced form and types-i, -ii, and -iii of the oxidized form. the frequency of the ligand-sensitive raman line suggested the coordination of lysine (nepsilon) at the sixth position of the heme iron of type-n. the sixth ligand of type-iii was deduced to be either lysine or histidine but would not b ...197720977
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