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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
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
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
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
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
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
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
continuous monitoring of the electrical potential across energy-transducing membranes using ion-selective electrodes. application to submitochondrial particles and chromatophores. 1978414935
regulation of adenosine diphosphate glucose pyrophosphorylase. 1978345767
[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
inhibition of energy conservation reactions in chromatophores of rhodospirillum rubrum by antibiotics. 1978147053
the interactions of coupling atpases with nucleotides. 1978147104
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
[effect of growth conditions on the activity of the enzymes of cyclic 3':5'-amp synthesis and decay in phototrophic bacteria].activity, ratio and summary content of cyclic amp enzymes, adenylate cyclase and phosphodiesterase varied depending on growth conditions of phototrophic bacteria (rhodospirillum rubrum and rhodopseudomonas palustris). it suggests, that membrane-bound and soluble enzymes carry different functions. the increase of adenylate cyclase under chaning growth conditions was usually accompanied by the increase of phosphodiesterase. sharp increase of both enzymes activity was observed when bacteria were gr ...1978207363
adenylate kinase from rhodospirillum rubrum.a partial purification and some properties of adenylate kinase from the photosynthetic bacterium rhodospirillum rubrum are described.1978207554
reduction of nicotinamide adenine dinucleotide by pyruvate:lipoate oxidoreductase in anaerobic, dark-grown rhodospirillum rubrum mutant c.cell extracts from fermentatively grown rhodospirillum rubrum reduced about 80 nmol of nicotinamide adenine dinucleotide (nad) per mg of protein per min under anaerobic conditions with sodium pyruvate. the reaction was specific for pyruvate and nad; nad phosphate was not reduced. results indicated that pyruvate-linked nad reduction occurred via pyruvate:lipoate oxidoreductase. the reaction required catalytic amounts of both coenzyme a and thiamine pyrophosphate. addition of sodium arsenite inhib ...1978207677
phenazine methosulfate mediated photoinactivation of some energy linked reactions in rhodospirillum rubrum. 1978208532
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
on the significance of electron transport systems for growth of rhodospirillum rubrum. 1978211972
facile assay of enzymes unique to the calvin cycle in intact cells, with special reference to ribulose 1,5-bisphosphate carboxylase. 1978204219
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
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
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
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
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
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
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
the proton pump is a molecular engine of motile bacteria. 197824186
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
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
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
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
flash-induced changes in the in vivo bacteriochlorophyll fluorescence yield at low temperatures and low redox potentials in carotenoid-containing strains of photosynthetic bacteria.the changes in the in vivo bacteriochlorophyll fluorescence induced by a xenon flash at low temperatures (77--200 k) with the "primary" acceptor x chemically prereduced have been examined in whole cells of several species of photosynthetic bacteria which contain carotenoids absorbing in the visible part of the absorption spectrum. two groups of species with different behaviour could be distinguished. in both cases a flash-induced rise of the fluorescence yield was observed with x prereduced at 7 ...197896856
resolution and reconstitution of rhodospirillum rubrum pyridine dinucleotide transhydrogenase: localization of substrate binding sites. 1978102261
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
[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
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
preparation of nitrogenase. 1978101737
involvement of an essential arginyl residue in the coupling activity of rhodospirillum rubrum chromatophores. 1978102254
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
energy-liked reactions in photosynthetic bacteria. x. solubilization of the membrane-bound energy-linked inorganic pyrophosphatase of rhodospirillum rubrum. 1978102323
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
the mechanism of reduction of the ubiquinone pool in photosynthetic bacteria at different redox potentials.(1) a flash number dependency of flash-induced absorbance changes was observed with whole cells of rhodospirillum rubrum and chromatophores of r. rubrum and rhodopseudomonas sphaeroides wild type and the g1c mutant. the oscillatory behavior was dependent on the redox potential; it was observed under oxidizing conditions only. absorbance difference spectra measured after each flash in the 275--500 nm wavelength region showed that a molecule of ubiquinone, r, is reduced to the semiquinone (r-) aft ...197899172
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
ribulose 1,5-bisphosphate carboxylase from autotrophic micro-organisms [proceedings]. 1978105954
ribulose bisphosphate carboxylases from chromatium vinosum and rhodospirillum rubrum and their role in photosynthetic carbon assimilation. 1978106836
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
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 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
picosecond detection of bchl-800 as an intermediate electron carrier between selectively-excited p870 and bacteriopheophytin in rhodospirillum rubrum relaction centers. 197897097
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
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
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
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
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
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
photosynthetic and respiratory electron flow in the dual functional membrane of facultative photosynthetic bacteria. 1978233518
resolution and reconstitution of rhodospirillum rubrum pyridine dinucleotide transhydrogenase: chemical modification with n-ethylmaleimide and 2,4-pentanedione. 197939595
[activation and inhibition of photoinduced proton absorption in rhodospirillum rubrum chromatophores by detergents and solvents].the effects of detergents (triton x-100) and solvents (diethyl ether, metanol) on the reversible light-induced proton uptake, photophosphorylation and band shift of the carotenoid in chromatophores from r. rubrum are described. all these compounds were found to stimulate the extent of light-induced proton uptake with subsequent inhibition when the concentrations were increased. stimulation of proton uptake is accompanied by inhibition of both phosphorylation and carotenoid absorbance shift.197937926
the kinetics of photooxidation of c-type cytochromes by rhodospirillum rubrum reaction centers. 197941489
blue and red shifts of bacteriochlorophyll absorption band around 880 nm in rhodospirillum rubrum.the redox potential dependence of the light-induced absorption changes of bacteriochlorophyll in chromatophores and subchromatophore pigment-protein complexes from rhodospirillum rubrum has been examined. the highest values of the absorption changes due to the bleaching of p-870 and the blue shift of p-800 in chromatophores and subchromatophore complexes are observed in the 360-410mv redox potential range. at potentials below 300 mv (ph 7.0), the 880 nm band of bacteriochlorophyll shifts to shor ...197941575
isolation, characterization, and crystallization of ribulosebisphosphate carboxylase from autotrophically grown rhodospirillum rubrum.serial culture of rhodospirillum rubrum with 2% co2 in h2 as the exclusive carbon source resulted in a rather large fraction of the soluble protein (greater than 40%) being comprised of ribulosebisphosphate carboxylase (about sixfold higher than the highest value previously reported). isolation of the enzyme from these cells revealed that it has physical and kinetic properties similar to those previously described for the enzyme derived from cells grown on butyrate. notably, the small subunit (w ...197933152
proton nuclear magnetic resonance studies of rhodospirillum rubrum cytochrome.rhodospirillum rubrum cytochrome c2 was studied by proton nuclear magnetic resonance at 220 mhz. assignments were made to the resonances of heme c by double-resonance techniques and by temperature-dependence studies. the aromatic resonances of trp-62 and tyr-70 of ferrocytochrome c2 were identified by spin-decoupling experiments. the resonances of the met-91 methyl group of the ferri- and ferrocytochromes were assigned by saturation-transfer experiments. the assignments are compared to those mad ...197934433
role of the large and small subunits of ribulose-1,5-bisphosphate carboxylase in the activation by co2 and mg2+. 197937245
the influence of energy-transfer inhibitors on proton permeability and photophosphorylation in normal and preilluminated rhodospirillum rubrum chromatophores.(1) chromatophores were preilluminated in the presence of phenazine methosulphate or diaminodurene, and without phosphorylation substrates; next they were transferred to fresh medium and assayed for light-induced proton uptake, light-induced 9-aminoacridin fluorescence quenching, and photophosphorylation. (2) preillumination in the presence of phenazine methosulphate or diaminodurene causes an inhibition of the photophosphorylation rate. the presence of adp + mgcl2 + phosphate, or adp + mgcl2 + ...197937903
[shifts of the bacteriochlorophyll absorption band at 880 nm in chromatophores and subchromatophore pigment-protein complexes from rhodospirillum rubrum].the redox potential dependency of the light-induced absorption changes of bacteriochlorophyll in the chromatophores and subchromatophore particles from rhodospirillum rubrum has been studied. the highest values of the absorption changes due to the bleaching of p870 and the blue shift of p800 are observed within the redox potential range of 360--410. at the potential values below 300 mv the 880 nm band of bacteriochlorophyll shifts to shorter wavelengths in the subchromatophore particles and to l ...197941599
manganese, an essential trace element for n2 fixation by rhodospirillum rubrum and rhodopseudomonas capsulata: role in nitrogenase regulation.nitrogenase (n(2)ase) from the photosynthetic bacterium rhodospirillum rubrum can exist in two forms, an unregulated form (n(2)ase a) and a regulatory form (n(2)ase r), the latter being identified in vitro by its need for activation by a mn(2+)-dependent n(2)ase activating system. the physiological significance of this mn(2+)-dependent n(2)ase activating system was suggested here by observations that growth of r. rubrum and rhodopseudomonas capsulata on n(2) gas (a condition that produces active ...197942641
oxonol dyes as monitors of membrane potential. their behavior in photosynthetic bacteria.the reponses of oxonol dyes to single and multiple single turnovers of the photosynthetic apparatus of photosynthetic bacteria have been studied, and compared with the responses of the endogenous carotenoid pigments. the absorbance changes of the oxonols can be conveniently measured at 587 nm, because this is an isosbestic point in the 'light-minus-dark' difference spectrum of the chromatophores. the oxonols appear to respond to the light-induced 'energization' by shifting their absorption maxim ...1979103582
characterization of a succinate dehydrogenase complex solubilized from the cytoplasmic membrane of bacillus subtilis with the nonionic detergent triton x-100.a succinic dehydrogenase (sdh) complex has been purified from triton x-100-solubilized membranes from bacillus subtilis by precipitation with specific antibody. radioactively labeled precipitated complex was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by autoradiography of the gels. the complex contained equimolar amounts of three polypeptides with approximate molecular weights of 65,000, 28,000, and 19,000. five succinic dehydrogenase-negative mutants, belongi ...1979108258
photooxidase activity of rhodospirillum rubrum chromatophores and reaction center complexes. the role of non-cyclic electron transfer in generation of the membrane potential. 1979109117
activation of ala synthetase by reduced thioredoxin in rhodopseudomonas spheroides y. 1979109312
modification of ribulose bisphosphate carboxylase from rhodospirillum rubrum with tetranitromethane. 1979110331
[noncyclic electron transport and membrane potential generation in the chromatophores of rhodospirillum rubrum]. 1979110361
two forms of nitrogenase from the photosynthetic bacterium rhodospirillum rubrum.acetylene reduction by nitrogenase from rhodospirillum rubrum, unlike that by other nitrogenases, was recently found by other investigators to require an activation of the iron protein of nitrogenase by an activating system comprising a chromatophore membrane component, adenosine 5'-triphosphate (atp), and divalent metal ions. in an extension of this work, we observed that the same activating system was also required for nitrogenase-linked h(2) evolution. however, we found that, depending on the ...1979106042
characterisation of reaction centers and their phospholipids from rhodospirillum rubrum.1. reaction centers from rhodospirillum rubrum have been extracted with the zwitterionic detergent lauryl dimethyl amine oxide. subsequent purification has been achieved by gel filtration and ion-exchange chromatography. the pure reaction centers are composed of three protein subunits (l, m, h), bacteriocholorophyll and bacteriopheophytin in the ratio 2 : 1 and phospholipids. 2. the phospholipid composition has been found to be similar to that of whole chromatophore membrane, except that diphosp ...1979109118
[use of urea by purple bacteria].strains of purple sulfur bacteria (chromatium minutissimum, ectothiorhodospira shaposhnikovii, thiocapsa roseopersicina, lamprobacter modestohalophilus) and nonsulfur bacteria (rhodopseudomonas palustris, rh. spheroides, rhodospirillum rubrum) grow in media containing urea as a source of nitrogen at concentrations from 0.5 to 5.0%. they can also utilize the carbon of urea and thus grow in the absence of bicarbonate. urea is decomposed by all the studied purple bacteria with the participation of ...1979112359
photoreaction center of photosynthetic bacteria. 2. size and quaternary structure of the photoreaction centers from rhodospirillum rubrum strain g9 and from rhodopseudomonas sphaeroides strain 2.4.1.the photoreaction center from rhodospirillum rubrum strain g9 binds about 6 times as much sodium dodecyl sulfate as certain proteins commonly used as molecular weight markers for sodium dodecyl sulfate--polyacrylamide gel electrophoresis. this presumably explains the apparent discrepancy between the molecular weight of the photoreaction center determined by electrophoresis (76 000) and its minimal molecular weight (87 000). the molecular weight of the photoreaction center solubilized with triton ...1979114213
[application of polarography to studies on redox systems in bio-membranes: especially on photosynthetic electron transport system in chromatophore membrane from photosynthetic bacterium (author's transl)]. 1979112648
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
[functional organization of the electron transport chain of rhodospirillum rubrum chromatophores in the absence of an exogenous electron donor]. 1979113038
a quantitative assay for bacterial rna polymerases. 1979114520
activation and regulation of ribulose bisphosphate carboxylase-oxygenase in the absence of small subunits.ribulose 1,5-bisphosphate carboxylase from rhodospirillum rubrum requires co2 and mg2+ for activation of both co2, both the carboxylase and oxygenase activities are stimulated by 6-phoshpo-d-gluconate, fructose 1,6-bisphosphate, 2-phosphoglycolate, 3-phosphoglycerate, nadph, and fructose 6-phosphate. the carboxylase activity is not activated by ribose 5-phosphate. the substrate, ribulose bisphosphate, neither activates nor inhibits the co2 and mg2+ activation of this enzyme. activation by co2 an ...1979114521
lipopolysaccharides of photosynthetic prokaryotes. 1979115382
changes in the acyl lipid composition of photosynthetic bacteria grown under photosynthetic and non-photosynthetic conditions.the acyl lipids and their constituent fatty acids were studied in the photosynthetic bacteria rhodospirillum rubrum, rhodopseudomonas capsulata and rhodopseudomonas sphaeroides, which were grown under photosynthetic and non-photosynthetic conditions. the major lipids were found to be phosphatidylethanolamine, phosphatidylglycerol and cardiolipin in each bacterium. the two rhodopseudomonas species also contained significant quantities of phosphatidylcholine. other acyl lipids accounted for less t ...1979115463
differential effects of metal ions on rhodospirillum rubrum ribulosebisphosphate carboxylase/oxygenase and stoichiometric incorporation of hco3- into a cobalt(iii)--enzyme complex.mg2+ or mn2+ ions supported both the carboxylase and oxygenase activities of the rhodospirillum rubrum ribulosebisphosphate carboxylase/oxygenase. for the carboxylase reaction, mn2+ supported 25% of the maximum activity obtained with mg2+; oxygenase activity, however, was twice as great with mn2+ as compared to that with mg2+. a further differential effect was obtained with co2+. co2+ did not support carboxylase activity and, in fact, was a strong inhibitor of mg2+-dependent carboxylase activity ...1979115489
two regimens of electrogenic cyclic redox chain operation in chromatophores of non-sulfur purple bacteria. a study using antimycin a.antimycin a causes a biphasic suppression of the light-induced membrane potential generation in rhodospirillum rubrum and rhodopseudomonas sphaeroides chromatophores incubated anerobically. the first phase is observed at low antibiotic concentrations and is apparently due to its action as a cyclic electron transfer inhibitor. the second phase is manifested at concentrations which are greater than 1--2 mum and is due to uncoupling that may be connected with an antibiotic-induced dissipation of th ...1979116681
short-lived delayed luminescence of photosynthetic organisms. i. nanosecond afterglows in purple bacteria at low redox potentials.a combined study of emissions of purple bacteria rhodospirillum rubrum, ectothiorhodospira shaposhnikovii and thiocapsa roseopersicina was performed under conditions of low potential. it has been shown that a considerable part of the emission represents a delayed luminescence with a lifetime of about 5 ns and an activation energy delta e = 0.05 +/- 0.03 ev. intensity of this delayed luminescence is approximately equal to that of prompt fluorescence. it diminishes as temperature decreases and als ...1979116682
disintegration of rhodospirillum rubrum chromatophore membrane into photoreaction units, reaction centers, and ubiquinone-10 protein with mixture of cholate and deoxycholate.1. the membrane of rhodospirillum rubrum chromatophores was disintegrated with mild detergents (cholate and deoxycholate) in order to study the spatial arrangement of the functional proteins in the photochemical apparatus and the electron transport system in the membrane. 2. the components solubilized from the membrane by a mixture of cholate and deoxycholate (c-doc) were separated into four fractions by molecular-sieve chromatography in the presence of c-doc; they were designated as f1, f2, f3, ...1979118165
removal of an adenine-like molecule during activation of dinitrogenase reductase from rhodospirillum rubrum.during the activation of the inactive dinitrogenase reductase from rhodospirillum rubrum, an adenine-like molecules is lost and phosphate is found on both active and inactive forms of the protein. atp and divalent metals are required for activation of the reduced protein, but atp is not required for activation of phenazine methosulfate-oxidized dinitrogenase reductase. snake venom diesterase and spleen diesterase have no effect on the inactive protein; alkaline phosphatase removes phosphate from ...1979118462
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
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
[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
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
characterization of the membrane-bound inorganic pyrophosphatase in rhodospirillum rubrum.the membrane-bound inorganic pyrophosphatase (ec 3.6.1.1) 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
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 vinosum.an 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
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