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light-induced division and genomic synchrony in phototrophically growing cultures of rhodopseudomonas sphaeroides.an experimental procedure for rapidly obtaining cell populations of phototrophically growing rhodopseudomonas sphaeroides which display division and genomic synchrony has been developed. the basis of the procedure resides with the normal physiological response displayed by cells of r. sphaeroides that have been subjected to an immediate decrease in incident light intensity. after an abrupt high- to low-light transition of an asynchronously dividing cell population, an immediate cessation of incr ...19817012139
the reaction center profile structure derived from neutron diffraction.both reaction center protein from the photosynthetic bacteria rhodopseudomonas sphaeroides and egg phosphatidylcholine can be deuterium labelled; the reaction center protein can be incorporated into the phosphatidylcholine bilayers forming a homogeneous population of unilamellar vesicles. the lipid profile and the reaction center profile within these reconstituted membrane profiles were directly determined to 32 a resolution using lamellar neutron diffraction from oriented membrane multilayers c ...19817016187
hexane-solubilised reaction centre proteolipid complexes of rhodopseudomonas sphaeroides.reaction centres from rhodopseudomonas sphaeroides, strain r-26, have been solubilised in hexane by the use of phospholipids and cations. two procedures have been developed: (i) a two-step technique involving the formation of detergent-free proteoliposomes from detergent solubilised reaction centres and phospholipids and mixing these with hexane in the present of cations; (ii) directly sonicating detergent-solubilised reaction centres with phospholipids before mixing with hexane and cations. the ...19817016190
comparison of the carotenoid bandshift and oxanol dyes to measure membrane potential changes during chemotactic stimulation of rhodopseudomonas sphaeroides and escherichia coli. 19817016583
[light-induced changes in ph and buffer capacity in reaction center preparations of rhodopseudomonas spheroides].in experiments with reaction centers (rc) preparations of rps. sphaeroides, strain 1760-1, ph of the suspension medium was found to change under continuous light excitation. the concentration of hydrogen ions starts to decrease fastly (t1/2 = 2--4 s) after the light is on, whereupon it increases slowly, to a steady-state level, within t1/2 = 5--7 min. during the fast phase 0.3 microm h+/1 microm of rc are absorbed and 7--8 microm h+/1 microm of rc are released under the slow phase. the fast phas ...19817017384
bacterial peptides with c-terminal similarities to bovine neurotensin.using radioimmunoassay, peptides resembling the c-terminal region of bovine neurotensin (nt) have been demonstrated in acid/acetone extracts of rhodopseudomonas palustris, escherichia coli, and caulaobacter crescentus. the nt-like bacterial components were shown to behave as peptides of small molecular weight (less than 2000) which were stable to acid and heat but labile to proteolytic digestion. in the radioimmunoassay toward nt they displayed dose-response curves parallel to standard and gave ...19817017622
membrane topography of the photosynthetic reaction center polypeptides of rhodopseudomonas sphaeroides.the topography of the photosynthetic reaction center (rc) polypeptides (h, m, and l) was investigated by proteolysis and radioiodination of membrane vesicles isolated from rhodopseudomonas sphaeroides. chromatophores, obtained from french-pressed cell lysates, are closed vesicles' and oriented inside out with respect to the cytoplasmic membrane (cytoplasmic side out). spheroplast-derived vesicles (sdvs), obtained after osmotic lysis of lysozyme-treated cells, are oriented right side in (periplas ...19817028090
[structural-functional characteristics of photosynthetic reaction centers extracted by treatment with lauryldimethylamine oxide from rhodopseudomonas sphaeroides (wild type)].a method for isolation of photoactive reaction centers from rps. sphaeroides (wild type) chromatophores, using lauryldimethylamine oxide (ldao) as detergent, is described. the preparation obtained is free of a light-harvesting pigment-protein complex and cytochromes. a high degree of purity can be demonstrated from the adsorption indexes of the preparation equal to a280 : a800 = 1.2--1.3; a760 : a800 : a870 = 1 : 2 : 0.9. data from polyacrylamide gel electrophoresis suggest that the integral pro ...19817028143
quinoprotein alcohol dehydrogenase from a non-methylotroph, acinetobacter calcoaceticus.acinetobacter calcoaceticus grown on ethanol contains an nad(p)+-independent alcohol dehydrogenase which resembles methanol dehydrogenase from methylotrophic bacteria in many respects. likewise, the prosthetic group of this enzyme appears to be identical to that of methanol dehydrogenase, namely, pyrrolo quinoline quinone. the organism is unable to grow on methanol, which means that quinoprotein alcohol dehydrogenases are not restricted to methylotrophs. arguments are presented for the idea that ...19817033448
low temperature excitation and emission spectroscopy of the photosynthetic bacteria rhodopseudomonas sphaeroides 'wild-type' strain atcc 17023.prompt and delayed emission of rhodopseudomonas sphaeroides 'wild-type' strain atcc 17023 was measured in the spectral range 550-950 nm at 1.7 k. the broad emission spectra could be resolved into separate bands by excitation spectroscopy. through a comparison of the separated excitation and emission spectra of the present study with absorption and fluorescence spectra of photosynthetic pigments given in the literature, the emitting species could be identified. beside the well-known pigments bact ...19816970593
optically excited triplet states in the bacteria rhodopseudomonas sphaeroides 'wild-type' detected by magnetic resonance in zero-field.optically-detected magnetic resonance (odmr) experiments in zero-field on the photosynthetic bacteria rhodopseudomonas sphaeroides revealed triplet states belonging to molecules which have a prompt emission in the optical region from 590 to 700 nm and a delayed emission between 700 and 830 nm. the zero-field parameters of these triplet states are 29 less than [d] less than 34 . 10(-3) cm-1 and 4 less than [e] less than 8 . 10(-3) cm-1, the decay rates of the [d] + [e] transitions being in the or ...19816970594
energy transfer between the carotenoid and the bacteriochlorophyll within the b-800-850 light-harvesting pigment-protein complex of rhodopseudomonas sphaeroides.energy transfer between carotenoid and bacteriochlorophyll has been studied in isolated b-800-850 antenna pigment-protein complexes from different strains of rhodopseudomonas sphaeroides which contain different types of carotenoid. singlet-singlet energy transfer from the carotenoid to the bacteriochlorophyll is efficient (75-100%) and is rather insensitive to carotenoid type, over the range of carotenoids tested. the yield of carotenoid triplets is low (2-15%) but this arises from a low yield o ...19816970595
in vivo intermembrane transfer of phospholipids in the photosynthetic bacterium rhodopseudomonas sphaeroides.the kinetics of accumulation of phospholipids into the intracytoplasmic membrane of rhodopseudomonas sphaeroides have been examined. we have previously demonstrated that accumulation of phospholipids in the intracytoplasmic membrane is discontinuous with respect to the cell cycle. in this study we demonstrated a sevenfold increase in the rate of phospholipid incorporation into the intracytoplasmic membrane concurrent with the onset of cell division. pulse-chase labeling studies revealed that the ...19816970743
dna-dna hybridization of rhodopseudomonas capsulata, rhodopseudomonas sphaeroides and rhodopseudomonas sulfidophila strains.the genetic relatedness of 21 rhodopseudomonas strains has been studied by means of dna-dna hybridization. all strains included in the study belonged to the subgroup of the genus rhodopseudomonas which is characterized by a short-rod to coccus morphology, a vesicular intracytoplasmic membrane system and carotenoids of the spheroidene group. mol percentages guanine + cytosine ranged from 64 to 73, most strains having values between 68 and 72. with few exceptions, the hybridization data obtained w ...19816971081
quantitative agreement between the values for the light-induced delta ph in rhodopseudomonas sphaeroides measured with automated follow-dialysis and 31p nmr. 19816971766
reconstitution of carotenoids into the light-harvesting pigment-protein complex from the carotenoidless mutant of rhodopseudomonas as sphaeroides r26.two carotenoids, neurosporene and spheroidene, have been successfully added to chromatophores from the carotenoidless mutant of rhodopseudomonas sphaeroides r26. carotenoids reconstituted in this way into the b-850 light-harvesting pigment-protein complex both sensitive bacteriochlorophyll fluorescence and protect the complex from the photodynamic reaction.19816972228
transient states in reaction centers containing reduced bacteriopheophytin.photosynthetic reaction centers isolated from rhodopseudomonas sphaeroides strain r-26 were excited with non-saturating 7-ps, 600-nm flashes under various conditions, and the resulting absorbance changes were measured. if the quinone electron acceptor (q) is in the oxidized state, flash excitation generates a transient state (pf), in which an electron has moved from the primary electron donor (p, a dimer of bacteriochlorophylls) to an acceptor complex involving a special bacteriopheophytin (h) a ...19816972229
orientation of intrinsic proteins in photosynthetic membranes. polarized infrared spectroscopy of chloroplasts and chromatophores.in order to estimate the degree of orientation of the alpha-helices of intrinsic proteins in photosynthetic membranes, polarized infrared spectroscopy has been used to measure the dichroism of the amide i and amide ii absorption bands of air-dried oriented samples of purple membranes, chloroplasts and chromatophores from rhodopseudomonas sphaeroides. using purple membrane, in which the orientation of the alpha-helices is precisely known (henderson, r. (1977) annu. rev. biophys. bioeng. 6, 87-109 ...19816972230
the balance between primary forward and back reactions in bacterial photosynthesis.the temperature dependence of the bacteriochlorophyll fluorescence and reaction center triplet yield in while cells of rhodopseudomonas sphaeroides strain 2.4.1 and of the magnetic field-induced fluorescence increase are calculated, taking into account rate constants of losses in the antenna system and of charge separation and recombination in the reaction center. triplet and singlet yield after recombination in the reaction center are described by the radical pair mechanism. good fits of the th ...19816972236
the non-detergent solubilization and isolation of intracytoplasmic membrane polypeptides from rhodopseudomonas sphaeroides.a nonspecific solubilization of the intracytoplasmic membrane proteins from rhodopseudomonas sphaeroides has been achieved in the absence of detergents. following removal of the photopigments and phospholipids by acetone/methanol extractions, the protein is quantitatively solubilized in 6 m guanidine thiocyanate which is subsequently exchanged by dialysis for 7 m urea. a urea-soluble protein fraction is obtained which represents 80% of the initial protein and qualitatively contains all the polyp ...19816972375
characterization of the three major intracytoplasmic membrane polypeptides isolated from rhodopseudomonas sphaeroides.the characterization of the three major membrane polypeptides indicated to be subunits of the light-harvesting bacteriochlorophyll-protein complexes of rhodopseudomonas sphaeroides is described. molecular weight determinations of the three polypeptides have been performed by sedimentation analysis and electrophoretic mobility and the values obtained were in agreement with each other as well as with those derived from compositional studies. nh2- and cooh-terminal amino acid determinations were pe ...19816972376
light-induced red shift of the qx absorption band of light-harvesting bacteriochlorophyll in rhodopseudomonas capsulata and rhodopseudomonas sphaeroides. 19816972735
31p nuclear magnetic resonance studies of energy transduction in rhodopseudomonas sphaeroides.31p nuclear magnetic resonance spectra of th phototrophic bacterium rhodopseudomonas sphaeroides reveal the presence of inorganic phosphate, sugar phosphates and two non-identified p,p1-diesterified pyrophosphate compounds. due to the presence of paramagnetic cations the resonances of these compounds can only be detected after repeated washing of the bacterial cells with a buffer, containing edta plus excess mg2+. washing with mg2+-free edta buffer deteriorates the structural integrity of the me ...19816972869
biosynthesis of delta-aminolevulinic acid in rhodopseudomonas sphaeroides. 19816973318
penicillin-binding proteins of rhodopseudomonas sphaeroides and their membrane localization.cytoplasmic membranes (cm) prepared from both chemotrophic and phototrophic cells of rhodopseudomonas sphaeroides possess penicillin-binding proteins (pbps), as demonstrated by binding of [125]furazlocillin to isolated membranes, the subsequent separation of the constituent pbps by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and their detection by autoradiography. the major pbp present in cm from r. sphaeroides corresponds in molecular weight to pbp-5, the predominant pbp present ...19816973568
procedures and conditions for application of the pyridine hemochrome method to photosynthetically grown cells of rhodopseudomonas sphaeroides.the conditions and pretreatments required in the conventional pyridine hemochrome method were re-examined for application of the method to the measurement of protoheme and heme c contents in photosynthetically grown cells of rhodopseudomonas sphaeroides. the amounts of hemes were calculated from two kinds of difference absorbances between two wavelengths of the redox difference spectrum of the pyridine hemochromes prepared from the disrupted cells. extraction of photosynthetic pigments from the ...19816974170
enthalpy and volume changes accompanying electron transfer from p-870 to quinones in rhodopseudomonas sphaeroides reaction centers.a capacitor microphone was used to measure the enthalpy and volume changes that accompany the electron transfer reactions, pqahv leads to p+q-a and pqaqbhv leads to p+qaq-b, following flash excitation of photosynthetic reaction centers isolated from rhodopseudomonas sphaeroides. p is a bacteriochlorophyll dimer (p-870), and qa and qb are ubiquinones. in reaction centers containing only qa, the enthalpy of p+q-a is very close to that of the pqa ground state (delta hr = 0.05 +/- 0.03 ev). the free ...19816974568
primary and secondary electron transfer in hexane-solubilized proteolipid complexes of rhodopseudomonas sphaeroides r-26. 19816975099
phospholipid topography of the photosynthetic membrane of rhodopseudomonas sphaeroides.the topography of phospholipids in the photosynthetic membranes of rhodopseudomonas sphaeroides was investigated by using purified chromatophores and spheroplast-derived vesicles (sdvs). chromatophores are closed vesicles oriented inside out with respect to the cytoplasmic membrane (cytoplasmic side out) and obtained from french-pressed cell lysates. sdvs are oriented right side out (periplasmic side out) and are obtained after osmotic lysis of lysozyme-treated cells. phosphatidylethanolamine (p ...19816975121
protoporphyrinogen oxidation in rhodopseudomonas spheroides, a step in heme and bacteriochlorophyll synthesis. 19816975600
control of porphyrin biosynthesis in rhodopseudomonas spheroides and propionibacterium shermanii. a direct 13c nuclear-magnetic-resonance spectroscopy study.the facultative anaerobes rhodopseudomonas spheroides and propionibacterium shermanii were grown under anaerobic and aerobic conditions. the effect of light was studied with the photosynthetic r. spheroides, and the adaptation of both species to dark anaerobic life was monitored by direct observation of 5-amino[5-13c]laevulinic acid metabolism by using 13c nuclear-magnetic-resonance spectroscopy.19816975620
mechanism of action of porphobilinogen deaminase. the participation of stable enzyme substrate covalent intermediates between porphobilinogen and the porphobilinogen deaminase from rhodopseudomonas spheroides.highly stable labelled complexes are formed between porphobilinogen deaminase and stoicheiometric amounts of [14c]porphobilinogen. on completion of the catalytic cycle by the addition of excess of substrate, the complexes yield labelled product and display all the properties expected from covalently bound enzyme intermediates involved in the deaminase catalytic sequence.19816975621
mobilization of the genes for photosynthesis from rhodopseudomonas capsulata by a promiscuous plasmid.plasmid pblm2, a derivative of rp1 with enhanced chromosome mobilization activity in rhodopseudomonas capsulata, was isolated by screening rare exconjugant clones for sex factor activity. pblm2 mobilized all known genes affecting photosynthesis as well as chromosomal genes for streptomycin and rifampin resistance and tryptophan and cytochrome biosynthesis. tight linkage was exhibited among the genes affecting photosynthesis. the frequency of successful transfer of chromosomal markers reached 6 x ...19816787008
[kinetics of the generation of a photo-induced electric potential in chromatophores of photosynthetizing bacteria].flash-induced formation of an electric potential difference (delta psi) was monitored by a direct method in chromatophores associated with the collodion phospholipid membrane. in rhodospirillum rubrum and rhodopseudomonas sphaeriodes chromatophores, the kinetics of delta psi generation exhibit fast (tau less than or equal to 0.3 microseconds) and slow (tau congruent to 200 microseconds) phases, the latter observed in the presence of exogenous quinones. comparison of the kinetic and potentiometri ...19816789146
[photooxidation and light-induced transport of phenazine methosulfate in chromatophores of purple bacteria].the light-induced interaction of phenazine methosulfate (pms) with chromatophores of the purple bacteria rhodospirillum rubrum and rhodopseudomonas sphaeroides was studied, using an ion-specific electrode. illumination caused an initial rapid increase in the concentration of methylphenazinium cation (mp+) and a subsequent slow (1-3 min) decrease of the mp+ concentration to a low steady level. the rapid phase of the light-induced mp+ concentration change is specifically enhanced by ascorbate. the ...19816789897
effect of oxygen on acetylene reduction by photosynthetic bacteria.the effect of dissolved oxygen concentration on nitrogenase activity was studied in three species of photosynthetic bacteria. the o2 concentration in the cell suspension was measured with an o2 electrode inserted into the reaction vessel. acetylene reduction by whole cells of rhodopseudomonas capsulata, rhodospirillum rubrum, and chromatium vinosum strain d was inhibited 50% by 0.73, 0.32, and 0.26 microm o2, respectively. the inhibition of the activity by o2 in r. capsulata usually was reversed ...19816790517
fast stages of photoelectric processes in biological membranes. iii. bacterial photosynthetic redox system.chromatophores of photosynthetic bacteria rhodospirillum rubrum, rhodopseudomonas sphaeroides and chromatium minutissimum were associated with a collodion film impregnated with a decane solution of asolectin. a very short light flash inducing a single turnover of the chromatophore photosynthetic redox system was found to induce the formation of an electrical potential difference amounting to 60 mv, directed across the film as measured with an orthodox electrometer technique. the main phase of th ...19816793358
high-potential iron-sulfur proteins and their possible site of electron transfer.the electron-transfer mechanism of the fe4s4 high-potential iron-sulfur proteins (hipip's) was explored via a stopped-flow spectrophotometric kinetic study of the reduction of chromatium vinosum and rhodopseudomonas gelatinosa hipip's by both native and trinitrophenyllysine-13 horse cytochrome c. the influence of electrostatic effects was also effectively partitioned from the redox process per se. the corrected rates were 12.3 x 10(4) and 3.8 x 10(4) m-1 s-1 for native with c. vinosum and r. gel ...19816260144
cytochrome b oxidation and reduction reactions in the ubiquinone-cytochrome b/c2 oxidoreductase from rhodopseudomonas sphaeroides.1. the kinetics of cytochrome b reduction and oxidation in the ubiquinone-cytochrome b/c2 oxidoreductase of chromatophores from rhodopseudomonas sphaeroides ga have been measured both in the presence and absence of antimycin, after subtraction of contributions due to absorption changes from cytochrome c2, the oxidized bacteriochlorophyll dimer of the reaction center, and a red shift of the antenna bacteriochlorophyll. 2. a small red shift of the antenna bacteriochlorophyll band centered at 589 n ...19816260161
resolved difference spectra of redox centers involved in photosynthetic electron flow in rhodopseudomonas capsulata and rhodopseudomonas sphaeroides.1. in rhodopseudomonas sphaeroides the qx absorption band of the reaction center bacteriochlorophyll dimer which bleaches on photo-oxidation is both blue-shifted and has an increased extinction coefficient on solubilisation of the chromatophore membrane with lauryldimethylamine-n-oxide. these effects may be attributable in part to the particle flattening effect. 2. the difference spectrum of photo-oxidisable c type cytochrome in the chromatophore was found to have a slightly variable peak positi ...19816260162
on the mechanism of photosynthetic electron transfer in rhodopseudomonas capsulata and rhodopseudomonas sphaeroides. 19816269602
an alternative pathway for the biosynthesis of isoprenoid compounds in bacteria.the pattern of incorporation of radioactivity from [1-14c]acetate and [2-14c]acetate into the polyprenyl side-chain of ubiquinones in bacteria (azotobacter vinelandii, pseudomonas sesami, escherichia coli and rhodopseudomonas capsulata) was studied. for this purpose, a new degradation method involving a modified barbier-wieland reaction of laevulinic acid was developed, and used along with the iodoform reaction. both c-1 and c-2 of acetate were incorporated exclusively into c-2 of laevulinic aci ...19816274317
temperature dependence of electron transfer between bacteriopheophytin and ubiquinone in protonated and deuterated reaction centers of rhodopseudomonas sphaeroides.the rate of the electron-transfer reaction between bacteriopheophytin and the first quinone in isolated reaction centers of rhodopseudomonas sphaeroides has an unusual temperature dependence. the rate increases about threefold with decreasing temperature between 300 and 25 k, and decreases abruptly at temperatures below 25 k. partial deuteration of the reaction centers alters the temperature dependence of the rate constant. qualitative features of the temperature dependence can be understood in ...19816275918
properties of six pesticide degradation plasmids isolated from alcaligenes paradoxus and alcaligenes eutrophus.biophysical and genetic properties of six independently isolated plasmids encoding the degradation of the herbicides 2,4-dichlorophenoxyacetic acid and 4-chloro-2-methylphenoxyacetic acid are described. four of the plasmids, pjp3, pjp4, pjp5, and pjp7, had molecular masses of 51 megadaltons, belonged to the incp1 incompatibility group, and transferred freely to strains of escherichia coli, rhodopseudomonas sphaeroides, rhizobium sp., agrobacterium tumefaciens, pseudomonas putida, pseudomonas flu ...19816257648
magnetic interactions between dysprosium complexes and two soluble iron-sulfur proteins.a tetranuclear ferredoxin from rhodopseudomonas gelatinosa [4fe-4s](+2,+3) has been examined by electron paramagnetic resonance techniques. the temperature-dependence and relaxation characteristics of the spectral lines indicate that the spin-lattice interaction is described at low temperatures by a t2 law which gives way to a t9 raman relaxation as the temperature is raised. at higher temperatures an orbach process becomes dominant. in the presence of dysprosium complexes the relaxation and lin ...19816257707
substrate specificity of citrate lyase deacetylase of rhodopseudomonas gelatinosa and rhodopseudomonas palustris.citrate lyase (ec 4.1.3.6) isolated from rhodopseudomonas palustris was investigated with regard to its kinetic properties and its subunit composition. this enzyme was inactivated by citrate lyase deacetylase (ec 3.1.2.-) of rhodopseudomonas gelatinosa. a corresponding cross-reaction was measured with partially purified deacetylase of r. palustris and citrate lyase of r. gelatinosa. the three different subunit types (alpha, beta, and gamma) of citrate lyase from r. gelatinosa wee purified to hom ...19816167565
molecular characterization of glutamine synthetase from the nitrogen-fixing phototrophic bacterium rhodopseudomonas palustris.the phototrophic bacterium rhodopseudomonas palustris assimilated ammonium via glutamine synthetase and glutamate synthase. diazotrophic and ammonium-grown cells had high levels of both enzymes, whereas enzymes of alternative assimilatory pathways were absent or had only low activities. glutamine synthetase was purified to electrophoretic homogeneity within three steps by dye-ligand and ion exchange chromatography. electron microscopy revealed a dodecameric molecular entity which was in accordan ...19816113716
inhibition of nitrogenase activity by metronidazole in rhodopseudomonas capsulata.inhibition of photosynthetic growth of rhodopseudomonas capsulata by metronidazole was dependent on the nitrogen supply in culture solutions. cultures fixing dinitrogen were more susceptible to inhibition by low concentrations than those supplied with nh4+. light-dependent c2h2 reduction and h2 production by washed cells were inhibited by 80% and 60% respectively by 1 mm metronidazole. when this compound was first reduced with h2-palladised asbestos prior to assay, it only partially restricted c ...19816116482
[the glutamine synthetase-glutamate synthase system in rhodopseudomonas sphaeroides].the phototrophic purple bacterium rhodopseudomonas sphaeroides, strain 2r, can assimilate ammonium by means of glutamine synthetase and glutamate synthase. a higher activity of glutamine synthetase is displayed by cells grown in the medium with glutamate or in the atmosphere of molecular nitrogen. the activity of glutamate synthase also rises when cells grow in the atmosphere of n2. however, in contrast to glutamine synthetase, the activity of glutamate synthase does not decrease in the presence ...19816118816
amino acid sequence of a peptide containing an essential cysteine residue of pig heart aconitase.pig heart aconitase reacts with one mole of phenacyl bromide per molecule to give complete inactivation due to the alkylation of a cysteine reside at the active site. a tryptic peptide containing this essential residue has been isolated and its amino acid sequence determined at ile-gln-leu-leu-cys *-pro-leu-leu-asn-gln-phe-asp-lys by manual methods and by the use of an automated solid phase sequencer. there is a limited similarity in amino acid sequence between this peptide and other peptides co ...19817213810
high-frequency chromosome transfer in rhodopseudomonas sphaeroides promoted by broad-host-range plasmid rp1 carrying mercury transposon tn501.insertion of the mercury resistance transposon tn501 into broad-host-range plasmid rp1 greatly enhanced the ability of this plasmid to promote chromosome transfer in the photosynthetic bacterium rhodopseudomonas sphaeroides. compared with the wild-type rp1, which produced less than 10(-8) recombinants per donor cell, rp1::tn501 produced between 10(-3) and 10(-7) recombinants per donor cell depending upon the marker selected. plasmid rp1::tn501 promoted polarized transfer of the chromosome from o ...19816263862
the establishment of mitochondria: paracoccus and rhodopseudomonas.many aerobic bacteria (both facultative and obligate) possess a number of those biochemical features of mitochondria which are concerned with energy metabolism. however, only restricted number, notably paracoccus denitrificans and rhodopseudomonas spheroides, have the majority of these features. the theory of endosymbiosis proposes that a primitive eukaryote took up bacteria to yield mitochondria. the present-day paracoccus then resembles the ancestral bacterium in many respects the primitive am ...19816264827
comparative studies of two membrane fractions isolated from chemotrophically and phototrophically grown cells of rhodopseudomonas capsulata.light and heavy membrane fractions have been isolated by equilibrium sucrose density centrifugation from rhodopseudomonas capsulata 938 gcm grown aerobically in the dark (chemotrophically) and anaerobically in the light (phototrophically). the densities of the light and heavy fractions from phototrophic cells were 1.1004 to 1.1006 and 1.1478, respectively, and the densities of the light and heavy fractions from chemotrophic cells were 1.0957 to 1.0958 and 1.1315, respectively. both fractions wer ...19817204341
energies and kinetics of radical pairs involving bacteriochlorophyll and bacteriopheophytin in bacterial reaction centers.absorbance changes reflecting the formation of a transient radical-pair state, p(f), were measured in reaction centers from rhodopseudomonas sphaeroides under conditions that blocked electron transfer to a later carrier (a quinone, q). the temperature dependence of the absorbance changes suggests that p(f) is an equilibrium mixture of two states, which appear to be mainly (1)[p([unk])b([unk])] and (1)[p([unk])h([unk])]. p is a bacteriochlorophyll dimer, b is a bacteriochlorophyll absorbing at 80 ...198116592980
b850 pigment-protein complex of rhodopseudomonas sphaeroides: extinction coefficients, circular dichroism, and the reversible binding of bacteriochlorophyll.chromatophores of rhodopseudomonas sphaeroides yield the antenna complex b850 in either of two states, depending on the method of isolation. methods using dodecyl (= lauryl) dimethylamine oxide yield b850 with an absorption spectrum like that in vivo: the bands at 800 and 850 nm, due to the bacteriochlorophyll (bchl) components bchl-800 and bchl-850, are in ratio a(800)/a(850) = 0.65 +/- 0.05. when b850 is isolated by methods using dodecyl sulfate, the bchl-800 is attenuated or absent. bchl assa ...198116593090
oxidation of c-type cytochromes by the membrane-bound cytochrome oxidase (cytochrome aa(3)) of blue-green algae.respiratory particles containing an aa(3)-type cytochrome oxidase were prepared from anacystis nidulans, synechocystis 6714, synechococcus lividus, anabaena variabilis, nostoc sp. strain mac, nostoc muscorum, and mastigocladus laminosus. oxidation of c-type cytochromes by membrane preparations of the different blue-green algae was observed using purified cytochromes from horse heart, candida krusei, tuna, saccharomyces oviformis, rhodospirillum rubrum, rhodospirillum molischianum, rhodopseudomon ...198216662253
regulation of nitrogenase in the photosynthetic bacterium rhodopseudomonas capsulata as studied by two-dimensional gel electrophoresis.by using two-dimensional electrophoresis, five putative soluble nif gene products were identified, and the regulation of nif gene expression in rhodopseudomonas capsulata was investigated. expression of nif was repressed by ammonia and atmospheric concentrations of oxygen. deprivation of molybdenum caused an interesting pattern of partial repression of nif gene expression that was not relieved by tungsten. these results are discussed in relation to the better understood system of nif regulation ...19826955301
purification of l-glutamate-dependent citrate lyase from clostridium sphenoides and electron microscopic analysis of citrate lyase isolated from rhodopseudomonas gelatinosa, streptococcus diacetilactis and c. sphenoides.citrate lyase from clostridium sphenoides was purified 72-fold with a yield of 11%. in contrast to citrate lyase from other sources the activity of this enzyme was strictly dependent on the presence of l-glutamate. the purified enzyme was only stable in the presence of 150 mm l-glutamate or 7 mm l-glutamate plus glycerol, sucrose or bovine serum albumin. changes of the l-glutamate pool and of enzyme activity in growing cells of c. sphenoides indicated that citrate lyase activity in this organism ...19826127210
the regulation of citrate lyase by acetylation/deacetylation. 19826128276
biosynthesis of bacterial glycogen: purification and structural and immunological properties of rhodopseudomonas sphaeroides adpglucose synthetase.adpglucose synthetase from the photosynthetic bacterium rhodopseudomonas sphaeroides was purified to greater than 95% purity. the molecular weight of the r. sphaeroides enzyme, as determined by sucrose density gradient ultracentrifugation, was approximately 204,000. the subunit molecular weight of the enzyme based on sodium dodecyl sulfate-gel electrophoresis was 46,000. although the amino acid composition of the enzyme was similar to that found for the enzymes from escherichia coli, salmonella ...19826178721
accumulation and retention of tritium (tritiated water) in rhodopseudomonas spheroides under aerobic condition. 19826179112
the in vitro transcription-translation of dna and rna templates by extracts of rhodopseudomonas sphaeroides. optimization and comparison of template specificity with escherichia coli extracts and in vivo synthesis.a dna-directed coupled transcription-translation system has been developed in cell-free extracts from the facultative phototroph, rhodopseudomonas sphaeroides. the in vitro protein-synthesizing system was active when prepared from either chemoheterotrophically or photoheterotrophically grown cells. optimal activity was dependent upon: use of extracts prepared freshly from early exponential phase cells, the method of cell breakage, and the length of preincubation of the extract (s-30), as well as ...19826184370
r-prime site-directed transposon tn7 mutagenesis of the photosynthetic apparatus in rhodopseudomonas capsulata. 19826296403
fructose-bisphosphatase from rhodopseudomonas palustris. 19826296614
phosphoenolpyruvate-dependent fructose phosphotransferase system of rhodopseudomonas sphaeroides: purification and physicochemical and immunochemical characterization of a membrane-associated enzyme i.the phosphotransferase system (pts) of the phototrophic bacterium rhodopseudomonas sphaeroides consists of a component located in the cytoplasmic membrane and a membrane-associated enzyme called "soluble factor" (sf) [saier, m. h., feucht, b. u., & roseman, s. (1971) j. biol. chem. 246, 7819--7821]. sf has been partially purified by a combination of hydrophobic interaction and ion-exchange and gel-permeation chromatography. sf is similar to escherichia coli enzyme i in its molecular characterist ...19826277369
photoelectric currents across planar bilayer membranes containing bacterial reaction centers. response under conditions of single electron turnover.light-induced electric current and potential responses have been measured across planar phospholipid membranes containing reaction centers from the photosynthetic bacterium rhodopseudomonas sphaeroides. under conditions in which the reaction centers are restricted to a single electron turnover, the responses can be correlated with the light-induced electron transfer reactions associated with the reaction center. the results indicate that electron transfer from the bacteriochlorophyll dimer to th ...19826277403
metal coordination centres of class ii cytochromes c.the class ii cytochromes rhodospirillum molischianum cytochrome c', rhodopseudomonas palustris cytochrome c556 and agrobacterium tumefaciens (b2a) cytochrome c556 have been investigated with a variety of spectroscopic techniques. the cytochrome c' was found to be high-spin and the two cytochromes c556 were found to be mainly low-spin and sx-coordinate with the fifth and sixth ligands being histidine and methionine. the implications of the different types of iron coordination are discussed.19826279397
energy coupling of facilitated transport of inorganic ions in rhodopseudomonas sphaeroides.within the scope of a study on the effects of changes in medium composition on the proton motive force in rhodopseudomonas sphaeroides, the energy coupling of sodium, phosphate, and potassium (rubidium) transport was investigated. sodium was transported via an electroneutral exchange system against protons. the system functioned optimally at ph 8 and was inactive below ph 7. the driving force for the phosphate transport varied with the external ph. at ph 8, pi transport was dependent exclusively ...19826281239
a rapid procedure for the isolation and purification of photosynthetic reaction centers from rhodopseudomonas sphaeroides r-26. 19826285830
purification and characterization of the cytochrome c oxidase from rhodopseudomonas sphaeroides.when grown aerobically in the dark, rhodopseudomonas sphaeroides develops a respiratory chain similar to that in mitochondria and the photosynthetic apparatus is suppressed. the aa3-type cytochrome c oxidase from rps. sphaeroides has been purified in triton x-100 by affinity chromatography with sepharose 4b coupled to yeast cytochrome c. the oxidase contains 14 nmol heme a/mg protein and is composed of three polypeptide subunits with relative molecular masses of 45000, 37000 and 35000. the enzym ...19826286309
magnetic field effects on the fluorescence of two reaction centerless mutants of rhodopseudomonas capsulata. 19826288044
a cytochrome b/c1 complex with ubiquinol--cytochrome c2 oxidoreductase activity from rhodopseudomonas sphaeroides ga.a cytochrome b/c1 complex which catalyses the reduction of cytochrome c by ubiquinol has been isolated from rhodopseudomonas sphaeroides ga. it contains two hemes b and substoichiometric amounts of ubiquinone-10 and of the rieske fe-s center per cytochrome c1, and is essentially free of reaction center and bacteriochlorophyll. the complex consists of three major polypeptides with apparent molecular masses of 40, 34 and 25 kda. the 34-kda polypeptide carries heme. cytochrome c1 has a midpoint pot ...19826290210
expression of the transposable lac operon tn951 in rhodopseudomonas sphaeroides.the transposon tn951 (lac) was introduced into the photosynthetic bacterium rhodopseudomonas sphaeroides 2.4.1, which is normally lac-, via the p-group plasmid rp1. beta-galactosidase was produced constitutively in both chemotrophically and phototrophically grown cells, and the levels were found to be the same but low. mutants were isolated, however, that were able to grow on lactose minimal medium and which expressed different levels of beta-galactosidase when grown chemotrophically or phototro ...19826290458
the complete amino acid sequence of nitrobacter agilis cytochrome c-550.the amino acid sequence of cytochrome c-550 from the chemoautotroph, nitrobacter agilis, was completed by using solid-phase sequencing and conventional procedures. the cytochrome was composed of 109 amino acid residues and its molecular weight was calculated to be 12375 including haem c. the cytochrome was homologous to eukaryotic cytochromes c and some photosynthetic bacterial cytochromes c2. in particular, its primary structure was very similar to that of rhodopseudomonas viridis cytochrome c2 ...19826291614
a q-cycle mechanism for the cyclic electron-transfer chain of rhodopseudomonas sphaeroides. 19826292019
cytochrome b/c complexes with polyprenyl quinol:cytochrome c oxidoreductase activity from anabaena variabilis and rhodopseudomonas sphaeroides ga: comparison of preparations from chloroplasts and mitochondria. 19826292024
localized energy coupling during photophosphorylation by chromatophores of rhodopseudomonas capsulata n22.the principle of the dual inhibitor titration method for testing models of electron-transport phosphorylation is outlined, and the method is applied to the study of photophosphorylation in bacterial chromatophores. it is concluded that energy coupling is strictly localized in nature in this system, in the sense that free energy released by a particular electron-transport chain may be used only by a particular h+-atp synthase. dual inhibitor titrations using the uncoupler sf 6847 and the h+-atp s ...19826293600
isolation and properties of the cytochrome b-c1 complex from rhodopseudomonas sphaeroides. 19826295373
[conjugation in rhodopseudomonas sphaeroides mediated by r plasmids].plasmids r68.45, rp4, rp4::mu cts62, rp1ts::tn10, rp1ts::tn9, rts1 and rp41 were transferred into cells of photosynthetic nitrogen-fixation bacterium rhodopseudomonas sphaeroides from escherichia coli and pseudomonas aeruginosa. the transfer of plasmids occurred with high frequency of 10(-1) to 10(-2) per donor cell in all cases. mobilization of r. sphaeroides 2r chromosome was obtained by rp4 and rts1 plasmids at a frequency of 10(-7) to 10(-8) per donor cell in all cases. mobilization of r. sp ...19826216140
purification and properties of the coupling-factor atpases f1 from rhodopseudomonas palustris and rhodopseudomonas sphaeroides.the coupling-factor atpases from photosynthetically grown rhodopseudomonas palustris and rhodopseudomonas sphaeroides were purified by the same procedure to homogeneity. gel chromatography on sephacryl s-300 superfine shortened the process of purification and improved its yield. solubilization of the atpase from both bacteria was found to be dependent on a specific sonication treatment of the cell suspensions, indicating a very weakly bound f1-atpase in r. palustris. depleted chromatophores coul ...19826217069
fermentation and anaerobic respiration by rhodospirillum rubrum and rhodopseudomonas capsulata.rhodospirillum rubrum and rhodopseudomonas capsulata were able to grow anaerobically in the dark either by a strict mixed-acid fermentation of sugars or, in the presence of an appropriate electron acceptor, by an energy-linked anaerobic respiration. both species fermented fructose without the addition of accessory oxidants, but required the initial presence of bicarbonate before fermentative growth could begin. major products of r. rubrum fermentation were succinate, acetate, propionate, formate ...19826798016
nitrogenase from the photosynthetic bacterium rhodopseudomonas capsulata: purification and molecular properties.nitrogenase proteins were isolated from cultures of the photosynthetic bacterium rhodopseudomonas capsulata grown on a limiting amount of ammonia. under these conditions, the nitrogenase n2ase a was active in vivo, and nitrogenase activity in vitro was not dependent upon manganese and the activating factor. the nitrogenase proteins were also isolated from nitrogen-limited cultures in which the in vivo nitrogenase activity had been stopped by an ammonia shock. this nitrogenase activity, n2ase r, ...19826799495
the effect of some varying lipid a structures on the inhibition of fibrillogenesis in basement membrane collagen.acid soluble basement membrane collagen (abmc) was prepared by extraction of the anterior lens capsules from bovine calf eyes in 0.5 m acetic acid in the presence of the protease inhibitors leupeptin and pepstatin. thermal aggregates formed from soluble basement membrane collagen were facilitated by heating (28 degree c) the collagen solutions in 0.15 m phosphate buffer. the effects of endotoxins derived from salmonella minnesota r595, chromobacterium violaceum an rhodopseudomonas viridis on the ...19826801242
[effect of oxygen and substrates for growth on the superoxide dismutase and catalase activity of microorganisms].the activity of superoxide dismutase (sod) and catalase in azotobacter vinelandii, citrobacter freundii, rhodopseudomonas capsulata, thiocapsa roseopersicina and spirulina platensis is far higher when the cultures are grown under the aerobic conditions. the activities of sod and catalase are higher in r. capsulata cells cultivated in a medium with glucose in the dark under the aerobic conditions than in cells grown under the same conditions but in the light. r. capsulata grown in a medium with g ...19826803110
glycerol-utilizing mutants of rhodopseudomonas capsulata.the isolation and study of glycerol-utilizing mutants of rhodopseudomonas capsulata indicated that the wild-type organism has genes capable of coding for the catabolism of glycerol but is unable to express them. furthermore, the genetic lesion in the original glycerol-utilizing mutant, l1, occurred very close to these genes.19826806249
photosynthetic bacterial reaction centers: interactions among the bacteriochlorophylls and bacteriopheophytins. 19826808895
[carbon monoxide utilization by anaerobic bacteria]. 19826815248
the electronic structure of fe2+ in reaction centers from rhodopseudomonas sphaeroides. ii. extended x-ray fine structure studies.extended x-ray absorption fine structure (exafs) studies were performed on reaction centers (rc) of the photosynthetic bacterium rhodopseudomonas sphaeroides r-26. rc containing two, one, and no quinones (2q, 1q, 0q) samples were studied. the average ligand distance of the first coordination shell was determined to be 2.10 +/- 0.02 a with a more distant shell at 4.14 +/- 0.05 a. the fe2+ site in rc was found to have a very large structural disorder parameter, from which a spread in ligand distan ...19826977381
an x-ray absorption study of the iron site in bacterial photosynthetic reaction centers.measurements were made of the extended x-ray absorption fine structure (exafs) of the iron site in photosynthetic reaction centers from the bacterium rhodopseudomonas sphaeroides. forms with two quinones, two quinones with added o-phenanthroline, and one quinone were studied. only the two forms containing two quinones maintained their integrity and were analyzed. the spectra show directly that the added o-phenanthroline does not chelate the iron atom. further analysis indicates that the iron is ...19826977382
rhodopseudomonas sphaeroides membranes: alterations in phospholipid composition in aerobically and phototrophically grown cells.the effects of growth conditions on phospholipid composition in rhodopseudomonas sphaeroides have been reexamined. the levels of phosphatidylethanolamine (27 to 28%), phosphatidylglycerol (23 to 24%), and phosphatidylcholine (11 to 18%) were very similar in cells grown aerobically or phototrophically at a high light intensity, consistent with findings for another member of rhodospirillaceae. in addition, an unknown phospholipid species was detected which comprised 20 to 30% of the total phosphol ...19826977537
fixation of dinitrogen derived from denitrification of nitrate in a photosynthetic bacterium, rhodopseudomonas sphaeroides forma sp. denitrificans.studies with 15n demonstrated that the phototrophic bacterium rhodopseudomonas sphaeroides forma sp. denitrificans strain il106 cannot assimilate no-3 but rather denitrifies it to n2. this strain also fixed n2 into cell protein, although nitrogenase activity was partially inhibited in the presence of no-3. strain il106 did not assimilate no-3, but growing cultures and washed cell suspensions incorporated the tracer from 15no-3 via denitrification to 15n2 and then via nitrogenase into cell nitrog ...19826977538
short-chain acyl-coenzyme a synthetases in rhodopseudomonas sphaeroides.two short-chain fatty acyl-coa synthetases were extracted from the photosynthetic bacterium, rhodopseudomonas sphaeroides, and partially purified by column chromatography on sephacryl s-200 and deae-cellulose. one enzyme activated propionate, valerate, acrylate, butyrate, and acetate, and was designated as propionyl-coa synthetase, since the highest activity and lowest km value (0.6 mm) were observed with propionate. the other enzyme activated acetate, propionate and acrylate. it showed the high ...19826978335
d-(--)-tartrate dehydratase of rhodopseudomonas sphaeroides: purification, characterization, and application to enzymatic determination of d-(--)-tartrate.an isolate of rhodopseudomonas sphaeroides was capable of growing phototrophically and chemotrophically (mu = 0.15 h(-1) for either condition) with d-(-)-tartrate as the carbon source. a d-(-)-tartrate dehydratase, (d-(-)-tartrate hydrolyase, ec 4.1.2.70) was induced in the presence of d-(-)-tartrate. the enzyme was purified 30-fold from cell extracts of r. sphaeroides to a specific activity of 7.5 u/mg of protein and was subsequently crystallized in the presence of 1 m kcl. the enzyme was homog ...19826978882
nitrate reductase from rhodopseudomonas sphaeroides.the facultative phototroph rhodopseudomonas sphaeroides dsm158 was incapable of either assimilating or dissimilating nitrate, although the organism could reduce it enzymatically to nitrite either anaerobically in the light or aerobically in the dark. reduction of nitrate was mediated by a nitrate reductase bound to chromatophores that could be easily solubilized and functioned with chemically reduced viologens or photochemically reduced flavins as electron donors. the enzyme was solubilized, and ...19826978883
purification and characterization of an n-acylphosphatidylserine from rhodopseudomonas sphaeroides.a new phospholipid that can account for up to 40% of the total cellular phospholipid of rhodopseudomonas sphaeroides has been identified. purification of the phospholipid was accomplished by column chromatography on silicic acid and diethylaminoethylcellulose followed by preparative thin-layer chromatography. a combination of spectroscopic and chemical techniques were used to identify the unknown phospholipid as an n-acylphosphatidylserine. infrared spectroscopy revealed the presence of both est ...19826980013
wavelength dependence of energy transduction in rhodopseudomonas sphaeroides: action spectrum of growth.we determined the wavelength dependence of the specific growth rate of rhodopseudomonas sphaeroides (the action spectrum of growth). a half-maximal (light-limited) growth rate was obtained when the culture vessel was illuminated with photon intensities between 0.8 x 10(14) and 3.5 x 10(14) photons cm-2 s-1 in the wavelength region between 400 and 950 nm. in the action spectrum, measured at 1.25 x 10(14) photons cm-2 s-1, distinct peaks could be observed at 480, 580, 800, and 870 nm, and minima c ...19826980219
carbon-13 nuclear magnetic resonance studies of acetate metabolism in intact cells of rhodopseudomonas sphaeroides.13c-nuclear magnetic resonance was used to study the metabolism of [2-(13)c]acetate in suspensions of rhodopseudomonas sphaeroides. in the dark, in logarithmic-phase cells the 13c label appeared first in butyrate c-2 and c-4 and subsequently in glutamate c-4 and succinate c-2 and c-3. in the light, synthesis of poly(beta-hydroxybutyrate) (phb) takes place. butyrate synthesis seems to be independent of phb synthesis or degradation activity. starved, logarithmic-phase cells also show massive synth ...19826980672
differential extraction and structural specificity of specialized ubiquinone molecules in secondary electron transfer in chromatophores from rhodopseudomonas sphaeroides, ga. 19826981381
genetic transformation of rhodopseudomonas sphaeroides by plasmid dna.a broad-host-range cloning vector, pui81, was constructed in vitro from plasmids rsf1010 and psl25 (a pbr322 derivative) and used to assay for transformation in rhodopseudomonas sphaeroides. washing cells with 500 mm tris was an effective means of inducing competence for dna uptake. transformation frequencies as high as 10(-5) (transformants per viable cell) have been achieved by incubating tris-treated cells with plasmid dna, 100 mm cacl2, and 20% polyethylene glycol 6000. maximum frequencies w ...19826981642
[study of ferredoxins in membranes of rhodopseudomonas spheroides by means of mossbauer spectroscopy].mössbauer spectra were investigated in membranes (chromatophores) of rhodopseudomonas sphaeroides, enriched in 57fe, over a temperature range from 4.2 to 300 k. the spectrum of isolated chromatophores is a symmetric doublet characterized by an isomeric shift delta=0.60+/-0.03 mm/s, quadrupole splitting delta=0.54+/-0.03 mm/s and a width gamma delta of 1.42+/-0.04 mm/3 at half maximum. these parameters, which are in fact characteristic of the mössbauer spectra of bacterial ferredoxins, appeared p ...19826981754
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