TitleAbstractYear(sorted ascending)
ribulose diphosphate oxygenase. v. presence in ribulose diphosphate carboxylase from rhodospirillum rubrum. 19744213364
the oxygenase activity of ribulose-1,5-bisphosphate carboxylase from rhodospirillum rubrum. 19744214241
the pigment complement of the photosynthetic reaction center isolated from rhodospirillum rubrum. 19744214257
glycollate formation and excretion by the purple photosynthetic bacterium rhodospirillum rubrum. 19744214718
an immunological and electrophoretic study of rhodospirillum rubrum chromatophore fragments. 19744215370
correlation between the level of vitamin-b12-dependent methionine synthetase and intracellular concentration of vitamin b12 in some bacteria. 19744215653
[phototaxis of microorganisms, its mechanism and relation to photosynthesis]. 19744216207
modulation by fumarate of a pi-insensitive pyruvate kinase from rhodopseudomonas capsulata. 19744216333
delta ph and membrane potential in bacterial chromatophores. 19744216516
activation of inactive nitrogenase by acid-treated component i.when azotobacter vinelandii was derepressed for nitrogenase synthesis in a n-free medium containing tungstate instead of molybdate, an inactive component i was synthesized. although this inactive component i could be activated in vivo upon addition of molybdate to the medium, it could not be activated in vitro when molybdate was added to the extracts. activation occurred, however, when an acid-treated component i was added to extracts of cells derepressed in medium containing tungstate. acid tre ...19744218230
bacteriocinogeny in the athiorhodaceae. 19744209388
aliphatic alcohols and bacterial motile behavior. 19744209798
photochemical disproportionation of sulfur into sulfide and sulfate by chlorobium limicola forma thiosulfatophilum. 19744209228
d-ribulose 1,5-diphosphate carboxylase from rhodospirillum rubrum. i. levels, purification, and effects of metallic ions. 19744208661
d-ribulose 1,5-diphosphate carboxylase from rhodospirillum rubrum. ii. quaternary structure, composition, catalytic, and immunological properties. 19744208662
[composition of nonconjugated pteridines in phototrophic bacteria]. 19744208903
origin of the atp formed during the light-dependent oxygen uptake catalyzed by rhodospirillum rubrum chromatophores.the oxygen uptake which is observed when rhodospirillum rubrum chromatophores are illuminated under air and in the presence of reduced 2, 6-dichlorophenolindophenol (dcip), 2, 3, 5, 6-tetra-methyl-p-phenylenediamine (diaminodurene, dad) or n, n'-tetramethyl-p-phenylenediamine (tmdp) depends on the electron-donor concentration according to the equation of michaelis-menten. the apparent km for the donor is lowered by the electron-transfer inhibitor 2-heptyl-4-hydroxyquinoline-n-oxide (hqno) which ...197547212
postillumination adenosine triphosphate synthesis in rhodospirillum rubrum chromatophores. ii. stimulation by a k+ diffusion potential.addition of valinomycin, nonactin, or monactin plus kcl in the dark to preilluminated chromatophores induced the synthesis of a large amount of atp. this stimulation of postillumination atp synthesis by a dark-imposed k+ diffusion potential was different from the stimulation caused by addition of permeant anions or cations in the light, since it increases when the ph of the light stage decreased from 8.0 to 6.0. it was thus most pronounced when the chromatophores were preloaded with protons but ...197549352
alcohol dehydrogenase activity of nonsulfur purple bacteria.rhodopseudomonas palustris, rh. viridis, rh. acidophila, and rhodomicrobium vanniellii grow on media containing ethanol, n-propanol, and n-butanol. the highest amount of lower alcohols is utilized by the strains of rh. palustris. only rh. acidophila accumulates methanol. alcohol dehydrogenase of rh. palustris, rh. viridis, and rhodospirillum rubrum requires for its activity nad, that of rhodomicrobium vanniellii--nadp, and the enzyme of rh. acidophila is active in the presence of phenazine metas ...19751631
polarographic studies on ubiquinone-10 and rhodoquinone bound with chromatophores from rhodospirillum rubrum.redox components bound with chromatophores of rhodospirillum rubrum, and pure samples of ubiquinone-10 and rhodoquinone were studied polarographically at 24 degrees. in a mixture of ethanol and water (4 : 1, v/v) at ph 7, ubiquinone-10 and rhodoquinone had half-wave potentials (e1/2) of +43 mv and -63 mv, respectively. for both quinones, values of the electron transfer number (n) were 2 , and plots of e1/2 versus ph formed straight lines with slopes of -30 mv/ph in the neutral ph range; thus, va ...19752586
d-alpha-hydroxyglutarate dehydrogenase of rhodospirillum rubrum.d-alpha-hydroxyglutarate dehydrogenase of r. rubrum grown anaerobically in the light was partially purified and some properties were investigated. 1. the enzyme catalyze stoichiometrically the dehydrogenation reaction of d-alpha-hydroxyglutarate into alpha-oxoglutarate, coupled with the reduction of 2, 6-dichlorophenolindophenol. 2. cytochrome c2, cytochrome c, and ferricyanide are effective as electron acceptors with the crude enzyme but not with the purified one, whereas nad+ and nadp+ are com ...19755424
effects of ph indicators on various activities of chromatophroes of rhodospirillum rubrum.1. the effects of ph indicators on activities for atp hydrolysis in the dark and atp-pi exchange in the dark were examined with chromatophores from rhodospirillum rubrum. of thirty-one ph indicators tested, eleven (metanil yellow, 2, 4-dinitrophenol, ethyl orange, bromocresol green, resazurin, neutral red, bromthymol blue, alpha-naphtholphthalein, o-cresolphthalein, phenolphthalein, and alizarin yellow g) almost completely inhibited the activities for atp formation and atp-pi exchange at concent ...19755425
spectroscopic properties of low-spin ferrous heme complexes and hemeproteins at 77degrees k. 1975164862
separation of respiratory reactions in rhodospirillum rubrum: inhibition studies with 2-hydroxydiphenyl.1. respiration of chemotrophically and phototrophically grown rhodospirillum rubrum is inhibited by 2-hydroxydiphenyl. 2. membrane-bound nadh oxidase and nadh: cytochrome c reductase are inhibited also. the inhibitor constant for both reactions (ki) is 0.075 plus or minus 0.012 mm. nadh dehydrogenase is not inhibited significantly. 3. the inhibition of succinate:cytochrome c reductase is associated for chemotrophic membranes with ki equals 0.22 plus or minus 0.03 mm and for phototrophic membrane ...1975164937
influence of light on the epr-detectable, electron transport components in whole cell rhodospirillum rubrum. 1975165557
models for antenna and reaction center chlorophylls. 1975166592
[photoformation of free radicals in the system bacteriochlorophyll--p-benzoquinone]. 1975166805
enzymes of glycollate formation and oxidation in two members of the rhodospirillacae (purple non-sulphur bacteria).1. phototrophic cultures of rhodomicrobium vanielii do not excrete glycollate when gassed anaerobically with nitrogen plus carbon dioxide, although the addition of alpha-hydroxy-2-pyridine methanesulphonate (hpms) results in the excretion of a trace amount of glycollate. the inclucion of low amounts of oxygen in this gas mixture results in marked glycollate excretion, higher rates occurring in the presence of hpms. 2. cell extracts of rhodomicrobium vannielii, and also of rhodospirillum rubrum, ...1975168831
conformational energy refinement of horse-heart ferricytochrome c.the reported x-ray structure of horse-heart ferricytochrome c has been refined by conformational energy calculations, using a three-stage computational procedure. in stage i, the atomic positions are adjusted to conform to idealized bond lengths and bond angles characteristic of small amino acid derivatives, while yet remaining as close as possible to the x-ray coordinates. in stage ii, atomic overlaps are eliminated by adjusting the backbone and side-chain dihedral angles to minimize the nonbon ...1975169878
letter: optically detected zero-field magnetic resonance studies of the photoexcited triplet state of the photosynthetic bacterium rhodosopirillum rubrum. 1975171297
role of ubiquinone-10 in electron transport system of chromatophores from rhodospirillum rubrum.the role of ubiquinone-10 in the activities for the reduction of free cytochrome c2 and bound cytochrome cc' by succinate was studied with chromatophores from a blue-green mutant (g-9) of rhodospirillum rubrum. 1. by a single extraction with isooctane, approximately 90% of ubiquinone-10 was easily removed from the chromatophores. in the extracted chromatophores, the activity for succinate-cytochrome c2 reduction decreased to 5-10% of the original activity. this depressed activity was mostly rest ...1975172493
characterization of two soluble ferredoxins as distinct from bound iron-sulfur proteins in the photosynthetic bacterium rhodospirillum an earlier investigation (shanmugam, k. t., buchanan, b. b., and arnon, d. i. (1972) biochim. biophys. acta 256, 477-486) the extraction of ferredoxin from rhodospirillum rubrum cells with the aid of a detergent (triton x-100) and acetone revealed the existence of two types of ferredoxin (i and ii) and led to the conclusion that both are membrane-bound. in the present investigation, ferredoxin and acid-labile sulfur analyses of photosynthetic membranes (chromatophores) and soluble protein ext ...1975172494
amino acid sequence of cytochrome c' from the purple photosynthetic bacterium rhodospirillum rubrum s1.the amino acid sequence of cytochrome c' from the purple photosynthetic bacterium rhodospirillum rubrum s1 has been determined and is consistent with homology to cytochrome c' from the nonphotosynthetic bacterium alcaligenes sp. ncib 11015. there is 29% identity in the chosen alignment of these two proteins. r. rubrum cytochrome c' is composed of a single peptide chain of 126 amino acid residues with a single heme covalently bound near the cooh terminus. there is no sequence similarity to mitoc ...1975172499
the photogeneration of superoxide by isolated photoreaction center from rhodospirillum rubrum. 1975173311
in vitro restoration of nitrate reductase: investigation of aspergillus nidulans and neurospora crassa nitrate reductase mutants.extracts of aspergillus nidulans wild type (bi-1) and the nitrate reductase mutant niad-17 were active in the in vitro restoration of nadph-dependent nitrate reductase when mixed with extracts of neurospora crassa, nit-1. among the a. nidulans cnx nitrate reductase mutants tested, only the molybdenum repair mutant, cnxe-14 grown in the presence of 10-minus 3 m na2 moo4 was active in the restoration assay. aspergillus extracts contained an inhibitor(s) which was measured by the decrease in nadph- ...1975123779
on the subunit composition of the coupling factor (atpase) from rhodospirillum rubrum. 1975124669
interaction of a coupling factor from rhodospirillum rubrum with coupling factor deficient chromatophores.a coupling factor necessary for the photophosphorylation and mg2+-atpase activities in rhodospirillum rubrum chromatophores has been separated from these particles. although the redox potential of coupling factor deficient chromatophores is slightly more oxidized than of the control, the addition of the coupling factor for reconstitution does not alter the redox potential. phenazine methosulfate cannot restore or significantly enhance the photophosphorylation activities of uncoupled or reconstit ...1975125569
immunological and fluorescence studies with the coupling factor atpase from rhodospirillum rubrum.1. purification of the coupling factor atpase from rhodospirillum rubrum has been achieved by a combination of a previously described procedure with chromatography on deae-sephadex a50. 2. identification of the coupling factor atpase during purification, and estimation of the relative amount of the enzyme in each fraction was greatly simplified by utilization of its unusual fluorescence. 3. preparations of r. rubrum coupling factor atpase injected into rabbits yielded antisera which were suitabl ...1975126080
effect of aurovertin on energy transfer reactions in rhodospirillum rubrum chromatophores. 1975131702
resolution and reconstitution of rhodospirillum rubrum pyridine dinucleotide transhydrogenase. proteolytic and thermal inactivation of the membrane component.pyridine dinucleotide transhydrogenase of the rhodospirillum rubrum chromatophore membrane was readily resolved by a washing procedure into two inactive components, a soluble transhydrogenase factor protein and an insoluble membrane-bound factor. transhydrogenation was reconstituted on reassociation of these components. the capacity of the membrane factor to reconstitute enzymatic activity was lost after proteolysis of soluble transhydrogenase factor-depleted membranes with trypsin. nadp+ or nad ...1975234441
a study on the membrane potential and ph gradient in chromatophores and intact cells of photosynthetic bacteria.generation of membrane potential (delta psi) and transmembrane ph difference (delta ph) was studied in ppi-energized chromatophores of rhodospirillum rubrum by means of measurements of carotenoid and bacteriochlorophyll absorption changes, atebrin and 8-anilinonaphthalene-1-sulphonate fluorescence responses, and phenyldicarbaundecaborane transport. the data obtained are consistent with the suggestion that carotenoid, bacteriochlorophyll and phenyldicarbaundecaborane responses are indicators of ...1975236031
characterization of the phototrap in photosynthetic bacteria. 1975237454
postillumination adenosine triphosphate synthesis in rhodospirillum rubrum chromatophores. i. conditions for maximal yields.the very low level of postillumination atp synthesis in chromatophores was markedly stimulated when permeant anions (thiocyanate or perchlorate) or permeant cations (potassium in the presence of valinomycin) were added to the light stage. although these compounds stimulated also light-induced proton uptake in chromatophores the ph dependence of both photoreactions was different. proton uptake peaked at ph 6.5 while the amount of postillumination atp was maximal when the light stage was carried o ...1975237896
the reaction of rhodospirillum rubrum cytochrome c2 with iron hexacyanides.the reaction of rhodospirillum rubrum cytochrome c2 with the nonphysiological reactants, ferrocyanide and ferricyanide has been investigated as a function of ionic strength, temperature and ph, using both stopped-flow and temperature-jump kinetic methods. the results are consistent with a complex reaction mechanism involving the formation of two intermediate complexes. the site of electron transfer appears to be at the front of the cytochrome c2 molecule near the hem e crevice with interacton of ...1975238661
[role of ferredoxin in the metabolism of hydrogen by rhodospirillum rubrum].ferredoxin was purified after isolation from the cells of rhodospirillum rubrum grown under photoheterotrophic conditions; a385/a280 in the absorption spectrum was not less than 0.53; the molecular weight was ca. 7700; e0' (ph 7.0)--430 mv. ferredoxin was easily reduced in the presence of dithionite and provided a high rate of nadp reduction by pea chloroplasts. the extracts of r. rubrum containing ferredoxin or the extracts, to which it was added, reduced nad in the presence of hydrogen and evo ...1975241001
[photoinduced liberation of hydrogen by bacteria, algae and higher plants]. 1975803442
generation of electric potential by reaction center complexes from rhodospirillum rubrum. 1975803460
comparison of two ferredoxins from rhodospirillum rubrum as electron carriers for the native coupling the reducing power of illuminated chloroplasts to the nitrogenase from photosynthetically grown rhodospirillum rubrum cells, one of the native ferredoxins. fdi, was found to be three times more effective than fdii.1975803490
[regulation of nitrogenase biosynthesis in microorganisms]. 1975803994
[action spectra of photosynthesis and liberation of hydrogen in bacteria, algae and higher plants]. 1975804393
carotenoid and merocyanine probes in chromatophore membranes. 1975804940
ribulose-1, 5-diphosphate carboxylase from rhadospirillum rubrum. 1975805893
ribulose-diphosphate carboxylase from the hydrogen bacteria and rhodospirillum rubrum. 1975805894
[change in the absorption spectra of carotenoids in dry films of rhodospirillum rubrum chromatophores in an external electric field].electrochromic spectra of carotenoids in dried films of chromatophores of rhodospirillum rubrum in 450-600 nm region are obtained. their good agreement with the photoinduced absorption changes of the same chromatophores under different conditions is shown.1975807260
[relation of chloroplast and chromatophore fluorescence yield to the state of the reaction centers]. 1975807465
[effect of temperature on the dark reduction of photooxidized bacteriochlorophyll p870 in rhodospirillum rubrum photosynthetic bacteria]. 1975809066
light-dependent atp formation in a non-phototrophic mutant of rhodospirillum rubrum deficient in oxygen photoreduction. 1975810144
carotenoid triplet states in reaction centers from rhodopseudomonas sphaeroides and rhodospirillum rubrum.purified photochemical reaction centers from three strains of rhodopseudomonas sphaeroides and two of rhodospirillium rubrum were reduced with na2s2o4 so as to block their photochemical electron transfer reactions. they then were excited with flashes lasting 5-30 ns. in all cases, absorbance measurements showed that the flash caused the immediate formation of a transient state (pf) which had been detected previously in reaction centers from rps. sphaeroides strain r26. previous work has shown th ...1975811259
regulation of nitrogenase synthesis in intact cells of rhodospirillum rubrum: inactivation of nitrogen fixation by ammonia, l-glutamine and l-asparagine.the synthesis of nitrogenase by intact cells of rhodospirillum rubrum was repressed in n-free media supplemented with l-glutamine or l-asparagine, but was unaffected by the presence of l-glutamate, l-aspartate or l-histidine. specific activities attained by cultures in supplemented media maintained under ar-co2 were 2 to 3 times higher than those in n-free medium under n2-co2. a loss in total activity occurred both in cultures growing with n2 after maximum activity had been reached, and in cultu ...1975811763
ultrastructural deformation studies on biological membranes.the ultrastructural deformation technique has been used to study various membranes, including several claimed to show subunit structure. with localized deformation fibers ca. 100-300 a in diameter and up to 4,000 a long were found extending across the cracks parallel to the draw direction in all membranes. lipid extraction and proteolytic enzyme (papain) treatment of membranes has shown that the fibers are protein in nature. deformation of membranes while still wet showed no significant change i ...1975813066
possible role of firmly bound atp in the energy transduction of photosynthetic membranes.chromatophores of rhodospirillum rubrum and spinach chloroplasts contain firmly bound atp that is rapidly labeled along with adp in the presence of 32pi and endogenous nucleotides. the labeling is not entirely dependent on light. in chloroplasts three types of bound atp can be defined methodologically by their extraction properties: buffer-soluble; acid-soluble; and sds-soluble or firmly bound atp. extensive washing of the chloroplasts does reduce buffer-soluble but not acid-soluble and firmly b ...1975813067
characterization of two cell-envelope fractions from chemotrophically grown rhodospirillum rubrum.two cell-envelope fractions were isolated from chemotrophically grown cells of rhodospirillum rubrum. on the basis of electron-microscopic investigations, chemical analysis, distribution of components involved in respiration, and poly-acrylamide gel electrophoresis, the heavy fraction (rho20 = 1.246 g per cm3) was identified as cell-wall, and the light fraction (rho = 1.145 g per cm3) as cyto-plasmic-membrane fragments. electron micrographs showed cell-wall fragments as open structures while cyt ...1975813575
[reversible photooxidation of bacteriochlorophylls a and b in aqueous solutions of detergents]. 1975813982
formation of beta-methylmalate and its conversion to citramalate in rhodospirillum rubrum.using a cell-free extract of rhodospirillum rubrum, studies were made of the condensation reaction between propionyl-coa and glyoxylate. when [14c]propionate was incubated with the extract in the presence of glyoxylate, atp, coa, mg2+, and mn2+, radioactivity was incorporated into several compounds. two of the main products were characterized as citramalate (cma) and erythro-beta-methylmalate (erythro-mma) on the basis of their behavior compared with authentic samples of cma and erythro-mma in t ...1975814116
primary reactions in photosynthesis. 1975814555
lipoic acid content of escherichia coli and other microorganisms.a mutant strain of escherichia coli k-12 requiring lipoic acid. w1485lip 2 (atcc 25645), was used to develop a turbidimetric assay for lipoic acid and a polarographic assay based on the oxidation of pyruvate by suspensions of lipoic acid-deficient organisms. the turbidmetric assay was more sensitive with a working range equivalent to 0.2-2.0 ng of dl-alpha-lipoic acid compared with 5-50 ng for the polarographic method. the mutant responded equally to racemic mixtures of alpha-lipoic acid, beta-l ...1975814874
[acid-soluble nucleotides of the phototrophic bacterium rhodospirillum rubrum during growth in light and in darkness].the content of acid-soluble nucleotides was different in the cells of non-sulphur purple bacterium rhodospirillum rubrum, growing phototrophically under anaerobic conditions and aerobically under conditions of heterotrophic nutrition. the cells of the culture growing in the darkness contained more adenylic and guanylic nucleotides, and the total of reduced and oxidized nadp. the cells of the culture growing in the light contained more fmn. the cells of the "light" and "dark" cultures contained g ...1975818480
[technique for the determination of the quantum yield of the primary process in the course of photosynthesis energy transformation. iii. experimental data obtained for different photosynthetic organisms].a relative method in two modifications has been developed for determination of the quantum yield of primary photosynthesis energy conversion. the purple bacteria e. chaposhnikovii and chr. minutissimum, r. rubrum chromatophores, cell extracts of e. shaposhnikovii, rps. spheroides strains ga and r-26, pigment-protein complexes from green bacterium chl. limicola and light subchloroplast particles, enriched in the photosystem i, were investigated. the quantum yields for all these objects were shown ...1975815784
unidirectional inhibition of phosphoenolpyruvate carboxykinase from rhodospirillum rubrum by atp.the kinetic and regulatory properties of partially purified phosphoenolpyruvate (pep) carboxykinase (ec from rhodospirillum rubrum were studied. the enzyme was active with guanosine- and inosinephosphates and must thus be classified as gtp (itp): oxaloacetate carboxylase (transphosphorylating.) in the direction of oxaloacetate-foramtion, the enzyme was strongly inhibited by atp (ki = 0.03 mm). itp, utp, ctp, and gtp were less inhibitory. the inhibition was competitive with respect to ...1976816325
new experimental approach to the estimation of rate of electron transfer from the primary to secondary acceptors in the photosynthetic electron transport chain of purple bacteria.a method for calculating the rate constant (ka1a2) for the oxidation of the primary electron acceptor (a1) by the secondary one (a2) in the photosynthetic electron transport chain of purple bacteria is proposed. the method is based on the analysis of the dark recovery kinetics of reaction centre bacteriochlorophyll (p) following its oxidation by a short single laser pulse at a high oxidation-reduction potential of the medium. it is shown that in ectothiorhodospira shaposhnikovii there is little ...1976816385
properties of ribonucleic acids from photosynthetic and heterotrophic rhodospirillum rubrum.rifampicin causes an initial rapid breakdown of about 30% of the pulse-labeled rna in both photosynthetic and heterotrophic rhodospirillum rubrum. an additional degradation of rna has been observed in the heterotrophic, but not in the photosynthetic cells at a later stage of rifampicin treatment. this secondary rna degradation is probably caused by breakdown of ribosomal rna, especially of the 23s species, as shown by polyacrylamide gel electrophoresis analyses. no qualitative difference between ...1976816437
cell-free, protein-synthesizing system of photosynthetic and heterotrophic rhodospirillum active in vitro protein-synthesizing system has been developed from rhodospirillum rubrum grown under either photosynthetic or heterotrophic conditions. a protease activity has been found in both of these systems, and this activity can be readily inactivated by treating the cells with kcl and phenylmethyl sulfonylfluoride. the difference in protein-synthesizing activity between the photosynthetic and the heterotrophic systems has been tested in regard to the requirement of various chemicals a ...1976816440
a novel short-lived emission from the photosynthetic bacterium rhodospirillum rubrum. 1976816674
triplet states of carotenoids from photosynthetic bacteria studied by nanosecond ultraviolet and electron pulse irradiation. 1976817340
[phototransformations of bacteriopheophytin in reaction centers of rhodospirillum rubrum and crhomatium minutissimum]. 1976817883
early formation of intracytoplasmic membranes in rhodospillum rubrum.cytoplasmic and intracytoplasmic membranes were isolated from rhodospirillum rubrum by equilibrium sucrose density gradient centrifugation. immediately after the induction of photosynthetically active intracytoplasmic membranes, bacteriochlorophyll is incorporated predominantly into the cytoplasmic membrane. with increasing pigment concentrations the newly arising intracytoplasmic membranes become sites of preferential bacteriochlorophyll incorporation. during this process the infrared absorptio ...1976819036
[purification and properties of rhodospirillum rubrum nadp-reductase].rhodospirillum rubrum cell extracts have active nadp-reductase capable of catalyzing the diaphorase reaction in the presence of methyl viologene or benzyl viologene and nadph-generating system. the greater part of nadp-reductase is localized in the soluble fraction of destroyed cells (90-10(3) g; 90 min). the purified preparation of nadp-reductase was found to contain 6 proteins, 4-5 of them possessing diaphorase activity. partially purified nadp-reductase preparation with a period of half-inact ...1976819042
[reconstruction of the function of membrane potential formation by isolated pigment-protein complexes of rhodospirillum rubrum].the pigment-protein complexes, containing the photosynthetic reaction centers and chlorophyll antenna, were isolated from non-sulfur purple bacteria rhodospirillum rubrum, by use of cholate. absorption spectra and quantum yield of photo-oxidation of bacteriochlorophyll p870 of complexes were similar to those of chromatophores. the procedure of reconstitution of proteoliposomes from phospholipids and complexes was proposed. the proteoliposomes incubated with coq6 and tmpd upon illumination are ge ...1976819043
motility in normal and filamentous forms of rhodospirillum suitable choice of medium, rhodospirillum rubrum has been grown both in normal (length 2 mum) and filamentous (length up to 60 mum) forms. both forms were highly motile, and negatively-stained preparations showed bipolar flagellated cells, with an average of seven flagella at each pole. motion consisted of a series of runs and tumbles, the ditribution of run time-lengths being poissonian. both forms tumbled in response to dark shock and showed negative chemotaxis to oxygen. the observation th ...1976819618
phototactic response of aerobically cultivated rhodospirillum rubrum.motile cells of aerobically cultivated rhodospirillum rubrum, containing no detectable bacteriochlorophyll, assembled at a spot of strong light projected through a dark-field condenser. far-red light was not effective, indicating that bacteriochlorophyll and thus photosynthetic metabolism was not responsible for the phenomenon. bacteria moving towards the centre of the light spot changed direction less frequently than those moving towards the margin. they also responded to temporal changes in th ...1976819621
measurement of transmembrane potentials in rhodospirillum rubrum chromatophores with an oxacarbocyanine dye.the fluorescent dye 3,3-dipentyloxacarbocyanine (occ) can be used as a fluorescence probe to measure transmembrane potentials across rhodospirillum rubrum chromatophore membranes. a reversible fluorescence increase is observed in the light which is sensitive to inhibitors, permeable ions and uncouplers. partial interchangeability between the electrical potential and the proton concentration gradient has been demonstrated by measurement of the fluorescence increase with occ and the fluorescence q ...1976820380
membranes of rhodospirillum rubrum: isolation and physicochemical properties of membranes from aerobically grown cells.highly purified preparations of cytoplasmic and outer membrane were isolated from aerobically grown rhodospirillum rubrum lysed by sequential treatment with lysozyme, ethylenediaminetetraacetate, and brij 58. the membranes were resolved and separated from other cellular constitutents by a combination of velocity and isopyknic sedimentation in sucrose density gradients. on the basis of their appearance in electron micrographs and their protein profiles in sodium dodecyl sulfate-polyacrylamide gel ...1976820689
membranes of rhodospirillum rubrum: physicochemical properties of chromatophore fractions isolated from osmotically and mechanically disrupted cells.isolation of highly purified membrane fractions from phototrophically grown rhodospirillum rubrum was achieved by velocity and isopyknic sedimentation under carefully controlled ionic conditions. bacteriochlorophyll-rich and succinic dehydrogenase-rich chromatophores that were essentially devoid of contamination by non-chromatophore protein were separated from a denser fraction in extracts disrupted in a french pressure cell. highly purified chromatophores and a nearly photopigment-free envelope ...1976820690
novel nucleotides from e. coli isolated and partially characterized. 1976821487
effects of 4-[beta-(diethylamino)-ethoxy]-benzophenone upon carotenogenesis in rhodospirillum rubrum.carotenoid production was determined in illuminated anaerobically maintained cultures of rhodospirillum rubrum in media with and without 4-[beta-(diethylamino)-ethoxy]-benzophenone. in treated cultures, lycopene--which normally is not produced by r. rubrum--accumulated as the predominant pigment, and total carotenoids increased five- to sixfold.1976821916
structural order in chromatophore membranes of rhodospirillum rubrum. 1976822349
a possible physiological function of the oxygen-photoreducing system of rhodospirillum rubrum.anaerobic suspensions of rhodospirillum rubrum cells which had been grown in the dark under low oxygen tension showed only a small increase of their atp content when illuminated for 30 s. the same suspensions failed to start immediate growth in the light. both high light-induced atp levels and immediate phototrophic growth were elicited by small amounts of oxygen which were insufficient by themselves to raise the atp levels or to support growth in the dark. the oxygen requirement for growth disa ...1976822793
photodichroic studies of the photoreaction center from rhodospirillum rubrum. i. attribution of p870 to two non parallel dipoles.a randomly oriented sample of photoreaction center prepared from rhodospirillum rubrum was excited at 77 degrees k by an actinic linearly polarized light of 870 nm. under such conditions, only those chromophores with components of their absorption dipoles oriented parallel to the polarization of the actinic light are bleached. the change in absorbance at 900 nm of this photoselected sample was observed while varying the angle of polarization of a weak measuring light. the polarization of the abs ...1976822873
photosynthetic regeneration of atp using bacterial chromatophores.we have demonstrated the use of bacterial chromatophores for the continuous photosynthetic regeneration of atp from adp in an ultrafiltration reactor. biphasic kinetics of the degradation of chromatophore activity are described. using chromatophores in combination with the enzyme adenylate kinase, we have also demonstrated continuous regeneration of atp from amp.1976822897
preparation and properties of bacterial chromatophores entrapped in polyacrylamide.the immobilization of rhodospirillum rubrum chromatophores was successfully performed by entrapping them in polyacrylamide. their photophosphorylating activity was about 40% of native chromatophores. the temperature and ph optima for immobilized chromatophores were similar to the native photosynthetic apparatus and kinetic parameters showed that the rate of photophosphorylation in polyacrylamide particles was diffusion controlled. light penetration of the gel particles was not a limiting paramet ...1976822898
inhibition of d-ribulose 1,5-bisphosphate carboxylase by pyridoxal 5'-phosphate. 1976823940
triplet states of bacteriochlorophyll and carotenoids in chromatophores of photosynthetic bacteria.chromatophores from photosynthetic bacteria were excited with flashes lasting approx. 15 ns. transient optical absorbance changes not associated with the photochemical electron-transfer reactions were interpreted as reflecting the conversion of bacteriochlorophyll or carotenoids into triplet states. triplet states of various carotenoids were detected in five strains of bacteria; triplet states of bacteriochlorophyll, in two strains that lack carotenoids. triplet states of antenna pigments could ...1976823977
functional and structural differences between photosynthetic and heterotrophic rhodospirillum rubrum ribosomes and s-100 fractions.cell-free, protein-synthesizing activity has been tested by using various combinations of the s-100 and ribosome fractions prepared from photosynthetic and heterotrophic rhodospirillum rubrum. the photosynthetic ribosomes are highly active when combined with either the photosynthetic or the heterotrophic s-100 fractions, whereas the heterotrophic ribosomes are active only when combined with the photosynthetic s-100 fraction. addition of a photosynthetic pigment-containing fraction to the homolog ...1976824038
activating factor for the iron protein of nitrogenase from rhodospirillum isolated from rhodospirillum rubrum, the iron protein of nitrogenase has little or no activity. it can be activated by incubating it with a trypsin-sensitive, oxygen-labile component (activating factor) plus adenosine triphosphate and a divalent metal ion. after activation, the iron protein retains its nitrogenase activity when the activating factor is removed.1976824729
reconstitution of biological molecular generators of electric current. bacteriochlorophyll and plant chlorophyll complexes.1. electric generation by bacteriochlorophyll reaction center complexes from rhodospirillum rubrum and by photosystem i complexes from pea chloroplasts has been studied. 2. the methods for the proteoliposome reconstitution from azolectin and bacteriochlorophyll- or plant chlorophyll-containing protein complexes have been elaborated. light-dependent electric responses of the proteoliposomes were detected using (a) phenyldicarbaundecarborane anion (pcb-) probe and (b) direct measurement by a voltm ...1976825514
naphxhylmercaptobenzoquinone, a new inhibitor of photophosphorylation in rhodospirillum rubrum chromatophores at the level of ubiquinone. 1976826250
[regulation of citrate synthese in bacteria: comparison of the action of various effectors on the enzymes of rhodospirillum rurbum and bacillus stearothermophilus].a comparative study of the citrate synthases purified from the facultatively photosynthetic bacterium rhodospirillum rubrum (gram negative) and the thermophile bacillus stearothermophilus (gram positive) was made. the citrate synthase from r. rubrum was activated by kcl (6-fold at 0.1 m kcl) and, less effectively, by nacl and nh4cl. its molecular weight was about 300,000. the enzyme was strongly inhibited by nadh, and this inhibition was counteracted by amp. the citrate synthase from b. stearoth ...1976826987
interrelationships among excited states in bacterial reaction centers. 1976830043
base competition of dna isolated from thiobacillus ferrooxidans grown on different substrates.the present study indicates some anomalies with respect to the dna base composition of thiobacillus ferrooxidans when it is cultured on different substrates. the % gc of the dna of this bacterium has been calculated by three different methods (melting temperature, cscl density gradient centrifugation and ultra-violet absorbancy ratios) using escherichia coli and rhodospirillum rubrum as references. the main values for t. ferrooxidans grown on ferrous iron, chalcopyrite and lead sulfide concentra ...1976981743
[bacteriochlorophyll fluorescence changes related to the bacteriopheophytin photoreduction in the chromatophores of purple sulfur bacteria].it is shown that illumination of chromatophores of sulfur bacterium chromatium minutissimum at eh of the medium --200 mv divided by --620 mv (when the photooxidation of pigment p890 is completely inhibited) induces a decrease in bacteriochlorophyll fluorescence yield, reversible in the dark. under these conditions a reversible photoreduction of bacteriopheophytin is detected (bleaching of absorption bands at 543 and 760 nm and development of a band at 650 nm), which is accompanied by a blue shif ...19761024595
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