PMID(sorted descending)
inactivation of ribulosebisphosphate carboxylase/oxygenase from rhodospirillum rubrum and spinach with the new affinity label 2-bromo-1,5-dihydroxy-3-pentanone 1,5-bisphosphate. 19816797428
lateral organization of proteins in the chromatophore membrane of rhodospirillum rubrum studied by chemical cross-linking.the organization of proteins in the chromatophore membrane, particularly of the reaction center and the light-harvesting polypeptide, was examined by the use of a hydrophobic and a hydrophilic cross-linking reagent, namely dsp (dithiobis-succinimidyl propionate) and glutaraldehyde. the linkage of proteins was studied by sds polyacrylamide pore gradient electrophoresis. dsp was shown to link proteins within the core of the membrane. the subunit h of the reaction center is linked with dsp at a low ...19816796574
[low-temperature device for fluorimetric studies]. 19816796132
the effects of bivalent cations on ribulose bisphosphate carboxylase/oxygenase.the half-saturation constants for binding of the bivalent cations (mg2+, ni2+, co2+, fe2+ and mn2+) to ribulose bisphosphate carboxylase/oxygenase from glycine max and rhodospirillum rubrum were measured. the values obtained were dependent on the enzyme and the cation present, but were the same for both oxygenase and carboxylase activities. ribulose bisphosphate rather than its cation complex was the true substrate. the kinetic parameters vmax.(co2), vmax.(o2), km(co2), km(o2), and k1(o2) were d ...19816796054
[study of chromophore dynamics by means of rayleigh scattering of mossbauer radiation].the temperature dependence of rayleigh scattering of mössbauer radiation was studied for two samples of the chromatophores with different relative humidity (p/ps = 0.35 and 0.94). new type of motion--the transitions between conformational substates was found above 200 degrees k. the model was developed to describe conformational motion in the membranes and membrane proteins. a new formula was derived for the debye--waller factor in accordance with this model. the model proposes the existence of ...19816795443
[kinetic model of the operation of a 2-electron switch in the photosynthetic reaction center of bacteria].a mathematical model, describing the binary oscillation of the concentration of semiquinone form of the secondary acceptor (ubiquinone) in photosynthetic reaction center of purple bacteria is proposed. this model takes into account both the changes of the ubiquinone state when the chromatophores are subjected to short flashes of light, and the successive dark relaxation of the semiquinone form. the model allows to calculate such characteristics as the dependence of the flash number, the stationa ...19816795442
ferredoxin excreted from photosynthetic bacterium, rhodospirillum rubrum: purification and properties.when the photoheterotroph, rhodospirillum rubrum, was grown in the light, ferredoxin was excreted from the cells in a significant amount, as well as hydrogenase. the extracellular ferredoxin was purified to a homogeneous state. the molecular weight was approximately 9,000, and the oxidation-reduction mid-potential was -0.29 v (n=1) at ph 7.0 and 25 degrees c. the amino acid composition was different from those of the intracellular ferredoxins, which were already known. the contents of non-heme i ...19816793564
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
steady-state measurements of delta ph and delta psi in rhodospirillum rubrum chromatophores by two different methods. comparison with phosphorylation potential.the ph gradient, delta ph, and the membrane potential, delta psi, formed during light-induced electron transport in rhodospirillum rubrum chromatophores were measured by two independent methods: (a) using specific electrodes to monitor light-dependent uptake of nh4cl and scn- at chromatophore concentrations of about 0.1 mg bacteriochlorophyll/ml and (b) using 9-aminoacridine and 8-anilinonaphthalenesulfonic acid as fluorescent probes for delta ph and delta psi, respectively, at chromatophore con ...19816793067
[role of cofactors in membrane potential generation by rhodospirillum rubrum chromatophores incorporated in a teflon filter].the chromatophores of the bacterium rhodospirillum rubrum were incorporated into a teflon filter impregnated with a decane solution of phospholipids and the light-induced electric potential difference (delta psi) between the aqueous phases separated by the filter was measured. the generation of delta psi in such a system at continuous light requires the presence of cofactors, i. e. artificial electron donors and acceptors. these cofactors provide for a steady-state flow of e by regenerating the ...19816791704
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
[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
sequences of tryptic peptides containing five cysteinyl residues of ribulosebisphosphate carboxylase/oxygenase from rhodospirillum rubrum. 19816789776
[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
[kinetics of ubisemiquinone redox changes in primary reactions of bacterial photosynthesis].absorbance changes at 450 nm of the semiquinone form of the secondary electron acceptor were studied in chromatophores of rhodospirillum rubrum. when chromatophores are illuminated by a series of single turnover flashes ubisemiquinone is formed and destroyed on alternate flashes at ambient redox potential from 100 to 250 mv. a simple kinetic model of the binary oscillations is suggested. on the base of the model it is shown that the rate constant of electron transfer from primary to secondary qu ...19816789145
[structural organization of membranes reconstituted from phospholipids and subchromatophore pigment-protein complexes].pigment--protein complexes of the p870 reaction centers and complexes of the bacteriochlorophyll light-harvesting antenna were isolated from the chromatophores of the non-sulfur purple bacterium rhodospirillum rubrum by solubilization with detergents. the proteoliposomes containing the reaction centers or reaction centers and the light-harvesting antenna as well as liposomes formed from phospholipids were obtained by a self-assembly procedure using seya bean phospholipids. the freeze-fracture st ...19806786374
control of 5-aminolevulinic acid synthetase activity in phototrophic facultative bacteria. purification and some properties of the enzyme from rhodospirillum rubrum. 19816786365
[study of microwave photolosses in chromatophores of photosynthesizing rhodospirillum rubrum bacteria].the study of photoinduced dielectric losses at frequency 10(10) c/s as function of samples humidity, heating and chemical treatment, intensity and wavelength of light is reported. the signals of microwave losses and differential spectrum signals are compared. the authors attribute the photolosses observed to the electrons localised in the realm between the primary and secondary acceptors during their reduction, probably being in the conductance quasiband of proteins in the photosynthetic reactio ...19816784778
[charge transfer in the primary processes of photosynthesis].transmission of electric charges generated by light in the unbranching chain of electron transport is under consideration. recombination of electrons and holes and possibility of reverse processes are considered. expression for the efficiency of steady-state charge separation is obtained. example of the reaction centre of bacterial photosynthesis is considered. all this permits to connect the signals of microwave photolosses with the destination of the electron on distant electron carriers.19816784776
a low-angle laser light scattering study of the association behavior of a major membrane protein of rhodospirillum rubrum chromatophore at various concentrations of sodium dodecyl sulfate where polypeptides derived from water-soluble globular proteins are solubilized monomerically.the major membrane protein of rhodospirillum rubrum chromatophore could be solubilized in the presence of free sodium dodecyl sulfate (sds) in concentration above 0.8 mm. at this concentration, the protein was highly associated to give a weight-averaged molecular weight as high as one million as determined by the low-angle laser light scattering technique. with the increase of free sds concentration, the aggregates were progressively dissociated to give a molecular weight of 8300 at the critical ...19816784770
x-ray diffraction studies on chromatophore membrane from photosynthetic bacteria. i. diffraction pattern of the photoreaction unit isolated from rhodospirillum rubrum chromatophore and some characteristics of the structure.the x-ray diffraction pattern from chromatophore membranes of a photosynthetic bacterium, rhodospirillum rubrum, indicates that a highly organized protein assembly exists in the membrane. the x-ray scatterer was solubilized from chromatophores by a mixture of cholate and deoxycholate. the basic component was identified as the photoreaction unit, which consists of light-harvesting bacteriochlorophyll proteins and a reaction center. the radial autocorrelation function, calculated directly from the ...19816783640
[cyclic electron transfer and membrane potential generation in chromatophores on non-sulfur bacteria rhodospirillum rubrum].the uptake of permeant anions by cells and chromatophores of the non-sulfur purple bacteria r. rubrum has been studied. antimycin a causes biphasic inhibition of the light-induced uptake of tetraphenylborate anions (tb-) by the cells and the isolated chromatophores incubated under anaerobic conditions. the first phase is observed at small concentrations of antimycin and is due to its effect as an inhibitor of the cyclic electron transfer. the second phase is observed at concentrations higher tha ...19806783130
the inhibition of photosynthetic electron transfer in rhodospirillum rubrum by n ,n' -dicyclohexylcarbodiimide.n ,n' -dicyclohexylcarbodiimide (dccd) at concentrations above 0.1 mm inhibits light-induced generation of a membrane potential in the course of cyclic and non-cyclic electron transfer, as well as light-induced oxygen uptake due to interaction of photoreduced secondary (loosely bound) ubiquinone with o2 in rhodospirillum rubrum chromatophores. similarly to o-phenanthroline, dccd blocks the electron transfer in the chromatophores between the primary (tightly bound) and secondary ubiquinones.19816781540
inhibition of nitrogenase activity by nh+4 in rhodospirillum rubrum.nitrogenase activities and the patterns of in vivo inhibition of nitrogenase by nh+4 were compared in rhodospirillum rubrum grown under several conditions of nitrogen availability. in cells grown on n2 or glutamate plus n2, nitrogenase activity was relatively low and was totally inhibited by added nh+4 in 15 to 20 min. in contrast, cells grown on glutamate alone displayed higher nitrogenase activity, and nh+4 had very little effect. cells grown on limiting amounts of nh+4 had lower nitrogenase a ...19816780531
[conformational mobility and theory of the mössbauer effect in biological systems. (model of a brownian oscillator strongly damped for conformational modes)].specific features of the mössbauer effect on proteins are discussed. it is found that the temperature dependence of recoilless gammaquantum absorption, f'(t), cannot be explained in terms of solid effects or diffusion spectrum broadening in liquids. a sharp decrease in f'(t) at temperature above 200 degrees k that has been found is due to the specificity of the conformational mobility of proteins and due to a smaller correlation time for spacially-confined diffusion of a mössbauer label tracer b ...19806777658
[thiosulfate oxidation by nonsulfur purple bacteria].the capability to oxidize thiosulfate was studied in 11 cultures of purple bacteria belonging to rhodomicrobium vannielii, rhodopseudmonas viridis, rh. sphaeroides, rh. capsulata, and rhodospirillum rubrum. all the bacteria oxidized thiosulfate under aerobic conditions in the dark. the strains 2r, 8259, a1, a2 and d1 of rh. sphaeroides oxidized thiosulfate under anaerobic conditions in the light, and the process was coupled with carbon dioxide fixation. all the strains contained thiosulfate redu ...19806777642
polarographic measurement of h2 in aqueous solutions. 19806776845
differences in the architecture of cytoplasmic and intracytoplasmic membranes of three chemotrophically and phototrophically grown species of the rhodospirillaceae.freeze-fracture faces of membranes of either chemotrophically or phototrophically grown rhodospirillum rubrum, rhodopseudomonas sphaeroides, and rhodospirillum tenue were analyzed. all three species differed from each other with respect to size as well as numerical density (number per square micrometer) of intramembrane particles. in r. rubrum the number of particles on exoplasmic fracture faces of the cytoplasmic membrane stayed nearly constant (about 900 particles per microns2), but on the pla ...19806776096
the photoreaction center of rhodospirillum rubrum mutant strain f24.1.rhodospirillum rubrum strain f24.1 is a spontaneous revertant of nonphototrophic mutant f24 derived from wild-type strain s1. strain f24 shows no detectable photochemical activity and contains, at most, traces of the photoreaction center polypeptides. strain f24.1 has a phototrophic growth rate close to that of the wild-type strain (picorel, r., del valle-tascón, s. and ramírez, j.m. (1977) arch. biophys. biochem. 181, 665-670) but shows little photochemical activity. light-induced absorbance ch ...19806775699
isolation and sequence of the pyridoxal 5'-phosphate active-site peptide from rhodospirillum rubrum ribulose-1,5-bisphosphate carboxylase/oxygenase.ribulose-1,5-bisphosphate carboxylase/oxygenase from rhodospirillum rubrum was modified with pyridoxal 5'-phosphate and then reduced with sodium borohydride. both carboxylase and oxygenase activities were lost when one molecule of pyridoxal 5'-phosphate was bound per enzyme dimer. peptide maps of modified enzyme showed one n6-(phosphopyridoxal)lysine-containing peptide. this peptide was isolated by gel filtration and cation-exchange chromatography and its sequence determined as ala-leu-gly-arg-p ...19806775695
effect of l-methionine-dl-sulphoximine on the photoproduction of hydrogen by rhodospirillum rubrum.the repression of photoproduction of hydrogen by ammonia could be relieved by l-methionine-dl-sulfoximine. in the absence of ammonia, hydrogen evolution was inhibited by concentrations of l-methionine-dl-sulfoximine higher than 0.1 mm.19806774882
evidence for a correlation between the photoinduced electron transfer and dynamic properties of the chromatophore membranes from rhodospirillum rubrum. 19806773810
carotenoid triplet yields in normal and deuterated rhodospirillum rubrum.quantum yields of carotenoid triplet formation in rhodospirillum rubrum wild type and fully deuterated cells and chromatophores were determined in weak laser flashes for excitation wavelength lambda i = 530 nm (mainly absorbed by the carotenoid spirilloxanthin) and for lambda i = 608 nm (mainly absorbed by bacteriochlorophyll) in the presence and absence of magnetic fields. all experiments were performed at room temperature and in the absence of oxygen. the quantum yield of reaction center bacte ...19806773564
[linear dichroism of pigments associated with spherical chromatophores. models of orientation in polyacrylamide gels].linear dichroism and orientation of pigments in chromatophores of photosynthetic bacteria chromatium minutissimum and rhodospirillum rubrum using a novel method of orientation in polyacrylamide gel was studied. a model is proposed for orientation of spherical membranes of chromatophores or other similar vesicules. the value of linear dichroism is derived for known deformation of the gel and a certain angle between the transition dipole and a unit vector perpendicular to the membrane plane. the a ...19806772937
[photoinduced changes in dielectric losses in the microwave region in chromatophores of rhodospirillum rubrum photosynthesizing bacteria]. 19806772240
[photoinduced changes in dielectric losses in the microwave region in rhodospirillum rubrum photosynthesizing bacteria]. 19806772239
energy transfer and bacteriochlorophyll fluorescence in purple bacteria at low temperature.emission spectra of bacteriochlorophyll a fluorescence and absorption spectra of various purple bacteria were measured at temperatures between 295 and 4 k. for rhodospirillum rubrum the relative yield of photochemistry was measured in the same temperature region. in agreement with earlier results, sharpening and shifts of absorption bands were observed upon cooling to 77 k. below 77 k further sharpening occurred. in all species an absorption band was observed at 751-757 nm. the position of this ...19806772218
the dependency of proton extrusion in the light on the developmental stage of the photosynthetic apparatus in rhodospirillum rubrum.the rate of proton extrusion by whole cells of rhodospirillum rubrum is constant on a bacteriochlorophyll basis only above cellular bacteriochlorophyll concentrations of about 10 nmol bacteriochlorophyll per mg cell protein. at specific bacteriochlorophyll cellular levels below this value, the rate of proton extrusion per bacteriochlorophyll increases. correspondingly, membrane preparations isolated from these cells exhibit increases in the rate of proton uptake on a pigment basis. concomitant w ...19806770898
formation of intracytoplasmic membranes in chemotrophic mecillinam sphaeroplasts of rhodospirillum rubrum.chemotrophically growing cells of rhodospirillum rubrum were transformed into sphaeroplasts of irregular shape under the influence of the penicillin antibiotic mecillinam. on a cell protein basis, respiratory activities of whole sphaeroplasts were slightly decreased as compared with the untreated control. but, on a membrane protein basis various activities of the respiratory chain were largely identical in membrane preparations from untreated cells and sphaeroplasts, respectively. chemotrophical ...19806769673
detection of cytochrome b+50 in membranes of rhodospirillum rubrum isolated from aerobically and phototrophically grown cells.1. dark equilibrium potentiometric titrations were conducted on membranes purified from rhodospirillum rubrum in an effort to identify b-type cytochrome components reported in other rhodospirillaceae. in preparations from aerobically grown cells virtually devoid of bacteriochlorophyll a, three components were observed at 560-540 nm. their oxidation-reduction midpoint potentials assigned by computer-assisted analysis were +195, +50 and -110 mv at ph 7.0; each of these fitted closely to theoretica ...19806769433
photo-induced electron transport and water state in rhodospirillum rubrum is shown that in bacterial chromatophores the pronounced changes in the free water content with a proton spin-spin relaxation time (t2) of 10(-3)--10(-2) s does not influence the efficiency of electron transfer from the photosynthetic reaction centre to the membrane pool of secondary acceptors. an abrupt inhibition of this process occurs only after the loss of the water with faster proton spin-spin relaxation time (t2 of 10(-4) s). the process is reversible. the water fraction in question is ...19806768386
short-lived delayed luminescence of photosynthesizing organisms. ii. the ratio between delayed and prompt fluorescence as studied by the modulation method.the ratio between the intensities of delayed and prompt fluorescence was studied for different photosynthetic objects under different conditions by modulation method. the method is based on excitation of luminescing objects by light, modulated harmonically, and on a combined study of phase shifts and demodulation coefficients of the luminescence as related to excitation light. the presence of intense delayed emissions was revealed in purple bacteria, ectothiorhodospira shaposhinokovii, rhodospir ...19806768385
purification and properties of polynucleotide phosphorylase from photosynthetic bacterium rhodospirillum rubrum.1. polynucleotide phosphorylase [polyribonucleotide: orthophosphate nucleotidyltransferase, ec] was purified to near homogeneity from the photosynthetic bacterium, rhodospirillum rubrum. the purified enzyme had a molecular weight of approximately 160,000, and consisted of two equivalent subunits of approximately 76,000 daltons. it catalyzed the three reactions described below. 2. in the exchange reaction of the beta-phosphate of nucleoside diphosphates with pi by the purified enzyme in t ...19806766923
polyadenylated messenger rnas code for photo reaction center and light-harvesting antenna polypeptides of rhodospirillum rubrum. 19806766405
activationless electron transfer processes in biological systems. 19806766403
molecular properties of fumarate reductase isolated from the cytoplasmic membrane of escherichia coli.fumarate reductase, purified from the cytoplasmic membrane of escherichia coli, has been cross-linked with the bifunctional reagent dimethylsuberimidate and shown to exist as an alpha beta dimer of polypeptides of molecular weights 69,000 and 25,000 in a 1:1 molar ratio. the protein has an s20,w of 7.67s and a d20,w of 6.5 x 10(-7) cm2/s. the purified enzyme contained 4-5 mol of nonheme iron and 4-5 mol of acid labile sulfur while the visible absorption spectrum showed a broad peak between 400 a ...19826751504
the effects of light and oxygen on membrane assembly in the photosynthetic bacteria. 19836617969
o-acetylserine sulfhydrylase and s-sulfocysteine synthase activities of rhodospirillum tenue.o-acetylserine sulfhydrylase in cell-free extracts of rhodospirillum tenue was markedly repressed after growth in the presence of sulfide or thiosulfate, whereas s-sulfocysteine synthase activity remained almost unchanged. purification on de52 cellulose resulted in the separation of two proteins: protein i with a molecular weight of 57000 had o-acetylserine sulfhydrylase activity only, while protein ii with a molecular weight of 46000 had s-sulfocysteine synthase activity in addition. the activi ...19836615127
[generic interrelations of purple bacteria in the genus rhodopseudomonas].the technique of dna--dna hybridization was used to study relations offween purple nonsulfur bacteria (the family rhodospirillaceae). the level of homologies with rhodopseudomonas sphaeroides 8259 was nearly the same for different species (8-17%) in the genus rhodopseudomonas under the conditions optimal for hybridization. the same level of homologies was found for the dna of rhodospirillum rubrum, a species belonging to another genus of purple nonsulfur bacteria (13%). rhodomicrobium vannielli ...19846610816
species variation in kinetic properties of ribulose 1,5-bisphosphate carboxylase/oxygenase.several kinetic parameters of ribulose-1,5-bisphosphate (rubp) carboxylase/oxygenase from different species were measured and compared. the co2/o2 specificity (vcko/vokc) was found to be about 80 in the enzymes from several c3 species and two c4 species. specificity values of 58 and 70, respectively, were found in enzymes from the c4 plants setaria italica and sorghum bicolor. two enzymes from cyanobacteria had values of about 50. substitution of mn2+ for mg2+ reduced the co2/o2 specificity by a ...19836582802
nitrogen fixation and nitrogenase activities in members of the family rhodospirillaceae.strains of all 18 species of the family rhodospirillaceae (nonsulfur photosynthetic bacteria) were studied for their comparative nitrogen-fixing abilities. all species, with the exception of rhodocyclus purpureus, were capable of growth with n2 as the sole nitrogen source under photosynthetic (anaerobic) conditions. most rapid growth on n2 was observed in strains of rhodopseudomonas capsulata. within the genus rhodopseudomonas, the species r. capsulata, r. sphaeroides, r. viridis, r. gelatinosa, ...19846581158
interaction of ribulose bisphosphate carboxylase/oxygenase with 2-carboxyhexitol 1,6-bisphosphates.2-c-carboxy-d-glucitol 1,6-bisphosphate (cgbp) and 2-c-carboxy-d-mannitol 1,6-bisphosphate (cmbp) have been synthesized, isolated, and the structures of these compounds and the derived lactones elucidated by nmr spectroscopy and periodate oxidation. both carboxyhexitol bisphosphates, which are homologs of the transition state analog 2-c-carboxy-d-arabinitol 1,5-bisphosphate, exhibit competitive inhibiton of ribulose bisphosphate carboxylase/oxygenase (ec isolated from spinach (spinacia ...19836573158
protein on the cell surface of the moderately halophilic phototrophic bacterium rhodospirillum salexigens.a cell surface protein (mr 68,000) of the moderately but obligately halophilic phototrophic bacterium rhodospirillum salexigens was identified by two independent methods: first, by labeling the cell surface with radioactive iodine and lactoperoxidase, and second, by washing cells in 30% sucrose to remove proteins attached to the cell surface by ionic bonds. the identified protein very likely represents the outermost layer of the cell envelope of r. salexigens as observed by electron microscopy. ...19846480555
unusual lipid a types in phototrophic bacteria and related species.photosynthetic bacteria of the rhodospirillaceae family (sulfur-free purple bacteria) possess lipopolysaccharides (lps) that deviate markedly from the salmonella lipopolysaccharides in the chemical makeup of the lipid a component and in their biologic properties. lps of rhodopseudomonas gelatinosa is highly toxic and pyrogenic, while that of rhodospirillum tenue shows cryptic toxicity. two lps types are completely non-toxic. the rhodopseudomonas sphaeroides lipid a has the same backbone as that ...19846474014
atp synthesis catalyzed by the atpase complex from rhodospirillum rubrum reconstituted into phospholipid vesicles together with bacteriorhodopsin. 19806451197
conversion of the ca2+-atpase from rhodospirillum rubrum into a mg2+-dependent enzyme by 1,n6-etheno atp. 19806448051
energy-linked reactions catalyzed by the purified atpase complex (f0f1) from rhodospirillum rubrum chromatophores.1. the isolation of f0f1-atpase complex from rhodospirillum rubrum chromatophores by the use of taurodeoxycholate is described. 2. the enzyme preparation contains about 12 polypeptides; five are subunits of the f1 moiety. 3. the atpase activity of the purified enzyme is dependent on the addition of phospholipids. 4. km-vales for mg2+-atp and ca2+-atp are similar to the values obtained for the membrane-bound enzyme. 5. the f0f1-atpase complex is more than 70% inhibited by oligomycin and n,n'-dicy ...19806447594
[pyrophosphate-dependent d-fructose-6-phosphate-phosphotransferase in rhodospirillaceae (author's transl)].a pyrophosphate-dependent fructose-6-phosphate phosphotransferase from the photosynthetic bacterium rhodospirillum rubrum was partially purified and characterized in respect to kinetic and regulatory properties. the enzyme had a molecular weight of about 95 000 dalton and required mg2+-ions for catalysis and maintenance of activity. the phosphotransferase was specific for fructose-6-phosphate (f-6-p) and inorganic pyrophosphate (pp) as substrates of the fructose-1,6-bisphosphate-forming reaction ...19806446207
x-ray diffraction studies on chromatophore membrane from photosynthetic bacteria. iii. basic structure of the photosynthetic unit and its relation to other bacteriochlorophyll forms.we have performed x-ray diffraction studies on photosynthetic units of rhodospirillum rubrum and solubilized *b800 + b890 complex from chromatophores of chromatium vinosum, to investigate the homology of their molecular structures. the native chromatophores of chromatium vinosum, which contain other bacteriochlorophyll forms, were examined by an x-ray diffraction technique, in order to assess the interactions between the complexes as well as the molecular structures of the bacteriochlorophyll fo ...19846442292
adenine nucleotide levels in rhodospirillum rubrum during switch-off of whole-cell nitrogenase activity.adenine nucleotide pools were measured in rhodospirillum rubrum cultures that contained nitrogenase. the average energy charge [([atp] + 1/2[adp])/([atp] + [adp] + [amp])] was found to be 0.66 and 0.62 in glutamate-grown and n-limited cultures respectively. treatment of glutamate-grown cells with darkness, ammonia, glutamine, carbonyl cyanide m-chlorophenylhydrazone, or phenazine methosulphate resulted in perturbations in the adenine nucleotide pools, and led to loss of whole-cell nitrogenase ac ...19846441571
[effect of dehydration on the primary picosecond stages of charge separation in rhodospirillum rubrum].effects of dehydration on the quantum yield of charge separation in the reaction centres, fluorescence and nanosecond recombination luminescence in r. rubrum chromatophores have been investigated. it has been shown that dehydration results in more than a 10 times decrease in the quantum efficiency of photosynthesis. besides, photoinduced fluorescence changes practically disappear in dehydrated samples and the parameters of nanosecond luminescence substantially change. these observations indicate ...19846441114
purification and properties of the activating enzyme for iron protein of nitrogenase from the photosynthetic bacterium rhodospirillum rubrum.the oxygen-labile, activating enzyme for iron protein from the photosynthetic bacterium, rhodospirillum rubrum, was purified 11,800-fold using a combination of chromatophore washing, de52-cellulose chromatography, hydroxylapatite chromatography, reactive red-120 cross-linked agarose chromatography, reactive red-120 cross-linked agarose chromatography, and sephadex g-75 gel filtration. activating enzyme appeared homogeneous on silver-stained sodium dodecyl sulfate-polyacrylamide gels, and the sta ...19846439722
the distribution of microsomal glutathione transferase among different organelles, different organs, and different the present study we have used both enzyme assay with 1-chloro-2,4-dinitrobenzene as substrate and immunochemical quantitation to examine the distribution of microsomal glutathione transferase in different organelles, in different organs, and in different organisms. this enzyme was found to constitute 3% and 5%, respectively, of the total protein recovered in the microsomal and outer mitochondrial membrane fractions from rat liver. microsomal glutathione transferase present in other subcellul ...19846439207
the mechanism of the attachment of esterifying alcohol in bacteriochlorophyll a biosynthesis.the mechanism through which the c-17(3) carboxy group of bacteriochlorophyllide a is esterified to produce bacteriochlorophyll aphytyl of rhodopseudomonas spheroides and bacteriochlorophyll ageranylgeranyl of rhodospirillum rubrum was studied by using 5-aminolaevulinate labelled with 18o at its c-1 carboxy oxygen atoms. the latter species was prepared by an exchange reaction in which 5-aminolaevulinate hydrochloride was heated in h218o in an autoclave. a method for the determination of the 18o c ...19846439193
nature and location of amide-bound (r)-3-acyloxyacyl groups in lipid a of lipopolysaccharides from various gram-negative has previously been demonstrated [eur. j. biochem. 124, 191-198 (1982) and 137, 15-22 (1983)] that the lipid a component of salmonella and proteus lipopolysaccharides contains amide-linked (r)-3-acyloxyacyl residues. in the present study lipid a of other gram-negative bacteria was analysed for the presence of amide-bound 3-acyloxyacyl residues. it was found that such residues are constituents of all lipid a tested (agrobacterium tumefaciens, chromobacterium violaceum, pseudomonas aeruginosa, ...19846437812
plasmidless, photosynthetically incompetent mutants of rhodospirillum rubrum.ethyl methanesulfonate rendered a high percentage of rhodospirillum rubrum cells plasmidless and photosynthetically incompetent (kuhl et al., j. bacteriol. 156:737-742, 1983). by probing restriction endonuclease-digested chromosomal dna from these plasmidless strains with 32p-labeled r. rubrum plasmid dna, we showed that no homology exists between the plasmid and the chromosomal dna of the mutant. loss of the plasmid in all the nonphotosynthetic isolates was accompanied by the synthesis of spiri ...19846434514
the light-harvesting polypeptides of rhodospirillum rubrum. ii. localisation of the amino-terminal regions of the light-harvesting polypeptides b 870-alpha and b 870-beta and the reaction-centre subunit l at the cytoplasmic side of the photosynthetic membrane of rhodospirillum rubrum g-9+.the unspecific proteinase k and the specific proteases alpha-chymotrypsin, trypsin and s. aureus v 8 protease were used in order to determine the orientation of the polypeptides b 870-alpha and b 870-beta from the major antenna complex b 870 of rs. rubrum g-9+ within the chromatophore membrane (inside-out vesicle). although b 870-alpha exhibits cleavable peptide bonds, treatment with specific proteases yielded splitting only in b 870-beta within the n-terminal region. in the case of proteinase k ...19846434397
the light-harvesting polypeptides of rhodospirillum rubrum. i. the amino-acid sequence of the second light-harvestng polypeptide b 880-beta (b 870-beta) of rhodospirillum rubrum s 1 and the carotenoidless mutant g-9+. carotenoidless mutant g-9+.the light-harvesting complex b 880 from rhodospirillum rubrum s 1 (wild type) and b 870 from the carotenoidless mutant g-9+ was shown to consist mainly of an organic solvent-(chloroform/methanol-) soluble and an organic solvent-insoluble polypeptide. the isolation and separation of these two low-molecular-mass polypeptides (mr 6101 and mr 6079) were achieved by a two-step extraction procedure of chromatophores using in the first step chloroform/methanol containing 0.1m ammonium acetate. followin ...19846434396
preliminary structural studies of ribulose-1,5-bisphosphate carboxylase/oxygenase from rhodospirillum rubrum.ribulose-1,5-bisphosphate carboxylase/oxygenase (ec from rhodospirillum rubrum has been crystallized in a form that is suitable for structural studies by x-ray diffraction. the asymmetric unit of the crystal contains one dimeric enzyme molecule of molecular mass 101,000 da. the enzyme was activated prior to crystallization and is presumed to be in the co2-activated state in the crystal. the method of hydrophobicity correlation has been used to compare the amino acid sequence of this mo ...19846432800
carbon monoxide dehydrogenase from rhodospirillum rubrum.the carbon monoxide dehydrogenase from the photosynthetic bacterium rhodospirillum rubrum was purified over 600-fold by deae-cellulose chromatography, heat treatment, hydroxylapatite chromatography, and preparative scale gel electrophoresis. in vitro, this enzyme catalyzed a two-electron oxidation of co to form co2 as the product. the reaction was dependent on the addition of an electron acceptor. the enzyme was oxygen labile, heat stable, and resistant to tryptic and chymotryptic digestion. opt ...19846430875
complete primary structure of ribulosebisphosphate carboxylase/oxygenase from rhodospirillum rubrum.of the 14 cyanogen bromide fragments derived from rhodospirillum rubrum ribulosebisphosphate carboxylase/oxygenase, four are too large to permit complete sequencing by direct means [f. c. hartman, c. d. stringer, j. omnaas, m. i. donnelly, and b. fraij (1982) arch. biochem. biophys. 219, 422-437]. these have now been digested with proteases, and the resultant peptides have been purified and sequenced, thereby providing the complete sequences of the original fragments. with the determination of t ...19846430239
preliminary x-ray diffraction study of ribulose-1,5-bisphosphate carboxylase from rhodospirillum rubrum.crystals from the dimeric enzyme ribulose-1,5-bisphosphate carboxylase of the photosynthetic bacterium rhodospirillum rubrum have been obtained from the gene product expressed in escherichia coli. the crystals are of the quarternary complex comprising enzyme: activator co2 (as a carbamate): mg2+: 2- carboxyarabinitol -1,5-bisphosphate (as a transition state analog). x-ray diffraction photographs show symmetry consistent with space group p4(1)2(1)2 or the corresponding enantiomorphic space group. ...19846427471
intermediates in the ribulose-1,5-bisphosphate carboxylase least two intermediates of the d-ribulose-1,5-bisphosphate carboxylase/oxygenase (ec reaction were liberated in detectable amounts when the functioning enzyme from rhodospirillum rubrum was quenched in acid. using substrate labeled with 32p in c-1, [32p]orthophosphate (pi) was found when the quenched solution was rapidly processed for extraction of pi as the acid molybdate complex. reaction with sodium borohydride under mildly alkaline conditions immediately after acid quenching of ...19846427222
effect of ammonia, darkness, and phenazine methosulfate on whole-cell nitrogenase activity and fe protein modification in rhodospirillum rubrum.a procedure for the immunoprecipitation of fe protein from cell extracts was developed and used to monitor the modification of fe protein in vivo. the subunit pattern of the isolated fe protein after sodium dodecyl sulfate-polyacrylamide gel electrophoresis was assayed by coomassie brilliant blue protein staining and autoradiographic 32p detection of the modifying group. whole-cell nitrogenase activity was also monitored during fe protein modification. the addition of ammonia, darkness, oxygen, ...19846427184
x-ray diffraction studies on photosystem i fragments from a blue-green alga, anabaena variabilis, and spinach.photosystem i fragments were prepared from thylakoid membranes of a blue-green alga (anabaena variabilis) and spinach by treatment with a detergent, triton x-100. equatorial x-ray diffraction patterns were recorded on films for oriented specimens of thylakoid membranes and photosystem i fragments. the thylakoid membranes and photosystem i fragments gave essentially the same equatorial diffraction patterns in both anabaena variabilis and spinach, indicating that the major x-ray scatterers in thes ...19846425276
x-ray diffraction studies on chromatophore membrane from photosynthetic bacteria. ii. comparison of diffraction patterns of photosynthetic units from various purple bacteria.comparative x-ray diffraction studies, in conjunction with infrared absorption spectroscopy, were performed on chromatophores isolated from various purple photosynthetic bacteria in order to achieve a better understanding of the molecular structure of the photosynthetic unit. purple non-sulfur bacteria used were rhodospirillum rubrum, rhodospirillum molischianum, rhodopseudomonas sphaeroides, and rhodopseudomonas palustris. chromatophores of chromatium vinosum, as a typical example of purple sul ...19846425275
the shape of ribulose bisphosphate carboxylase/oxygenase in solution as inferred from small angle neutron scattering.small angle neutron scattering of both activated and deactivated hexadecameric ribulose bisphosphate carboxylase/oxygenase from spinach revealed that its structure in solution very closely resembles that determined for the deactivated crystalline enzyme from tobacco (baker, t.s., eisenberg, d., and eiserling, f. (1977) science 196, 293-295). scattering from both forms of the enzyme in h2o most closely fits that expected from a hollow sphere with an outer radius of 56.4 a and inner radius of 14.3 ...19846423629
chemical nature of protein complex of photoreaction unit including reaction center in chromatophores of photosynthetic bacterium, rhodospirillum rubrum, as detected by successive dissociation method.reaction center of chromatophores of rhodospirillum rubrum consists of three kinds of protein, h-, m-, and l-subunit, and is bound with many other kinds of protein to form a larger protein complex (pru; photoreaction unit), which contains all the bacteriochlorophyll. in the present study, purified pru was dissociated in a stepwise manner in the presence of various mixtures of lithium dodecyl sulfate, sodium cholate and/or sodium deoxycholate, and separated into five, smaller protein complexes (p ...19836423620
2-[8-14c]naphthyl 2-diazo-3,3,3-trifluoropropionate, a new carbene generating reagent for probing hydrophobic membrane domains.a new precursor of a lipophilic photolabel, 2-[8-14c]naphthyl 2-diazo-3,3,3-trifluoropropionate (nadit) has been synthesized. the suitability of the reagent for labeling the hydrophobic core of membranes is demonstrated by studying its reactivity in chromatophores of rhodospirillum rubrum g-9+. the label binds preferentially to the phospholipids and intrinsic membrane proteins. in isolated reaction centers treated with nadit the hydrophobic subunits m and l are more labeled than the h subunit. t ...19846422985
2-(4-bromoacetamido)anilino-2-deoxypentitol 1,5-bisphosphate, a new affinity label for ribulose bisphosphate carboxylase/oxygenase from rhodospirillum rubrum. determination of reaction parameters and characterization of an active site peptide.a new affinity label for ribulose bisphosphate carboxylase/oxygenase from rhodospirillum rubrum, 2-(4-bromoacetamido)anilino-2-deoxypentitol 1,5-bisphosphate, has been prepared, reductive amination of ribulose-p2 with p-phenylenediamine in the presence of sodium cyanoborohydride yielded an epimeric mixture which was resolved by chromatography on quaternary aminoethyl-sephadex. subsequent bromoacetylation of the isolated amino bisphosphates gave reagents a and b (ribo and arabino epimers of 2-(4- ...19846421817
uptake of methionine sulfoximine by some n2 fixing bacteria, and its effect on ammonium transport.the n2 fixing bacteria klebsiella pneumoniae, azospirillum brasilense, rhodopseudomonas sphaeroides and rhodospirillum rubrum, but not azotobacter vinelandii accumulate the glutamine analogue methionine sulfoximine in the cell. in the accumulating cells methionine sulfoximine inhibits ammonium transport. accumulation and inhibition are prevented by glutamine.19836418571
inhibition of ribulose bisphosphate carboxylase by substrate ribulose 1,5-bisphosphate.substrate ribulose bisphosphate is a potent and a weak inhibitor of the rate of co2/mg2+ activation in the carboxylase purified from spinach leaves and rhodospirillum rubrum, respectively. at 2 degrees c, the concentration of ribulose bisphosphate required for 50% inhibition of the initial rate of co2/mg2+ activation was less than 0.4 microm for the spinach enzyme, but between 67 and 270 microm for the r. rubrum carboxylase. activator 14co2 trapping experiments demonstrated that ribulose bisphos ...19836417133
[dicyclohexylcarbodiimide as an inhibitor of light- and pyrophosphate-induced formation of membrane potential in chromatophores of purple bacteria].n,n'-dicyclohexylcarbodiimide (dccd) suppresses the uptake of penetrating tetraphenylborate anions by rhodospirillum rubrum chromatophores during cyclic and non-cyclic electron transfer and atp and pp i hydrolyses. the photochemical activity of the bacteriochlorophyll reaction centers of the chromatophores in insensitive to dccd. this supports the view that dccd inhibits the electron transfer between the primary and secondary quinones of the photosynthetic chain. incorporation of the chromatopho ...19836414533
[intramolecular dynamics and electron transfer in photosynthetic reaction centers. a study using luminescence].the temperature dependences of fluorescence and phosphorescence spectra maxima of chromophor labels--endogenic (tryptophan) and exogenic (eosinisothiocyanate)--were measured for the preparations of photosynthetic membranes and reaction centers from rhodospirillum rubrum. it was found that the dipole mobility of protein-lipid matrix in the vicinity of the chromophores intensified markedly with a temperature rise from 150 to 300k resulting in the corresponding relaxation time tau r decrease from 1 ...19836413837
the role of mg2+ and mn2+ in the enzyme-catalysed activation of nitrogenase fe protein from rhodospirillum rubrum.the activation of the fe protein of nitrogenase (rr2) from glutamate-grown rhodospirillum rubrum by activating enzyme (ae) was investigated. ae is confirmed to have mr about 20 000 and is shown to operate catalytically. there is a role in activation for metal-ion-atp, which can be met by either mnatp or mgatp. there is also a site of action for free metal ions. this site prefers mn2+ (apparent kd approx. 20 microm) over mg2+ (apparent kd approx. 20 mm) by a factor of 1000-fold. non-activated rr2 ...19836412690
structure of the extracellular ferredoxin from rhodospirillum rubrum: close similarity to clostridial ferredoxins.the amino acid sequence of an [8fe-8s] ferredoxin isolated from the culture medium of rhodospirillum rubrum, a photosynthetic purple non-sulfur bacterium, was determined by a combination of various conventional procedures. the sequence was a-y-k-i-e-e-t-c-i-s-c-g-a-c-a-a-e-c-p-v-n-a-i-e-q-g-d-t-i-f-v-v-n-a-d-t-c-i-d-c - g-n-c-a-n-v-c-p-v-g-a-p-v-a-e (55 amino acid residues). it lacked methionine, leucine, histidine, arginine, and tryptophan. the molecular weight was calculated to be 5,568 exclud ...19836411697
architectonic natures of proteins bound to rhodospirillum rubrum chromatophores as detected by trypsin treatment and sonication. 19836409893
ribulose bisphosphate carboxylase/oxygenase in toluene-permeabilized rhodospirillum rubrum.toluene-permeabilized rhodospirillum rubrum cells were used to study activation of and catalysis by the dual-function enzyme ribulose bisphosphate carboxylase/oxygenase. incubation with co2 provided as hco3-, followed by rapid removal of co2 at 2 degrees c and subsequent incubation at 30 degrees c before assay, enabled a determination of decay rates of the carboxylase and the oxygenase. half-times at 30 degrees c with 20 mm-mg2+ were 10.8 and 3.7 min respectively. additionally, the concentration ...19836409101
incorporation of adenine into the modifying group of inactive iron protein of nitrogenase from rhodospirillum rubrum.adenine was fed to cells of rhodospirillum rubrum grown on glutamate. the adenine was found to be incorporated into the modifying group of the inactive form of iron protein. adenine labelled in the 8-position ([8-3h]adenine) and the 2-position ([2-3h]adenine) was specifically incorporated into the electrophoretic 'upper-band' subunit of iron protein. incorporation of label from the 2-position into many proteins was observed if histidine was not present in the medium. label was removed by the act ...19836409076
[interaction of redox mediators with chromatophores of the photosynthetic bacterium rhodospirillum rubrum]. 19836408397
hybridization of cloned rhodopseudomonas capsulata photosynthesis genes with dna from other photosynthetic bacteria.the homology of rhodopseudomonas capsulata dna segments carrying photosynthesis genes with sequences present in total dna from certain other photosynthetic and non-photosynthetic bacterial species was determined by hybridization. r. capsulata dna fragments that carry loci for production of peptide components of the photosynthetic reaction center and light-harvesting i antenna complex were found to hybridize to dna from some photosynthetic species. however, fragments that carry carotenoid or bact ...19836406432
action of chlorophyllase purified from rye seedlings on light-harvesting bacteriochlorophyll of chromatophores and spheroplasts from rhodospirillum rubrum.1. the chlorophyllase [ec] purified from greened rye seedlings hydrolyzed the bacteriochlorophyll isolated from rhodospirillum rubrum, but not the pigment bound to the membrane of chromatophores or spheroplasts from the bacterium. 2. acetone, if added at such concentrations that the bound bacteriochlorophyll would not be solubilized, enabled the enzyme to hydrolyze the bound pigment. the acetone concentrations required for half the maximum hydrolysis rates were 16% with chromatophores a ...19836404894
isolation and sequencing of an active-site peptide from rhodospirillum rubrum ribulosebisphosphate carboxylase/oxygenase after affinity labeling with 2-[(bromoacetyl)amino]pentitol 1,5-bisphosphate.2-[(bromoacetyl)amino]pentitol 1,5-bisphosphate was reported to be a highly selective affinity label for ribulosebisphosphate carboxylase/oxygenase from rhodospirillum rubrum [fraij, b., & hartman, f. c. (1982) j. biol. chem. 257, 3501-3505]. the enzyme has now been inactivated with a 14c-labeled reagent in order to identify the target residue at the sequence level. subsequent to inactivation, the enzyme was carboxymethylated with iodoacetate and then digested with trypsin. the only radioactive ...19836404301
adenine nucleotide levels in and nitrogen fixation by the cyanobacterium anabaena sp. strain 7120.adenine nucleotide levels were determined in whole filaments of anabaena sp. 7120 grown under different n2-fixing or non-n2-fixing conditions. these were compared with levels in isolated heterocysts, rhodospirillum rubrum, and azotobacter vinelandii. adenine nucleotides in whole filaments of anabaena sp. do not reflect the energetic expense of n2 fixation as they do in r. rubrum and a. vinelandii. however, adenine nucleotide levels in heterocysts were similar to the levels found in n2-fixing r. ...19836403506
[purification of adenyl cyclase from the phototrophic bacterium rhodospirillum rubrum]. 19836403060
identification of two distinct lactate dehydrogenases in rhodospirillum rubrum.the activities of pyridine nucleotide-independent d- and l-lactate dehydrogenases were detected in membranes from rhodospirillum rubrum grown under aerobic and phototrophic conditions. crossed immunoelectrophoretic analysis revealed two antigenically distinct enzymes that were further distinguished by specificity for d- and l-stereoisomers of lactate and by the sensitivity of the d-lactate dehydrogenase to inhibition by oxamate and oxalate.19836402502
overproduction of nitrogenase by nitrogen-limited cultures of rhodopseudomonas palustris.rhodopseudomonas palustris cells grown on limiting nitrogen produced four- to eightfold higher nitrogenase specific activity relative to cells sparged with n2. the high activity of n-limited cells was the result of overproduction of the nitrogenase proteins. this was shown by four independent techniques: (i) titration of the mo-fe protein in cell-free extracts with fe protein from azotobacter vinelandii; (ii) direct detection of the subunits of mo-fe protein by sodium dodecyl sulfate-polyacrylam ...19836402491
derepression of the synthesis of d-ribulose 1,5-bisphosphate carboxylase/oxygenase from rhodospirillum rubrum.the synthesis of ribulose 1,5-bisphosphate carboxylase/oxygenase in rhodospirillum rubrum was greatly influenced by the conditions of culture. when grown photolithotrophically in an atmosphere containing low levels of co2 (1.5 to 2%), enzyme synthesis was derepressed, with the result that the enzyme comprised up to 50% of the soluble protein of the cells as determined by immunological quantitation. this response was not observed when r. rubrum was grown photolithotrophically in an atmosphere of ...19836401286
cloning and expression in escherichia coli of the form ii ribulose 1,5-bisphosphate carboxylase/oxygenase gene from rhodopseudomonas sphaeroides.the gene encoding the form ii ribulose 1,5-bisphosphate carboxylase/oxygenase (rubpc/o) from rhodopseudomonas (r.) sphaeroides has been identified on a 3-kb ecori fragment and cloned into a broad-host-range, high-copy-number plasmid, using the gene from rhodospirillum (rs.) rubrum as a hybridization probe. subclones of the gene from r. sphaeroides in pbr322 and puc8 show substantial levels of expression and enzymatic activity in whole cells and crude cell extracts of escherichia coli. this enzym ...19846396166
molecular cloning of the phosphoenolpyruvate carboxylase gene, ppc, of escherichia coli.the cole1 hybrid plasmid, plc20-10, carrying the ppc gene and the argecbh gene cluster of escherichia coli k-12, was characterized. the ppc gene coding for phosphoenolpyruvate carboxylase (ec, was subcloned into the plasmid pbr322 to give the plasmids ps2 and ps3. these plasmids carried a 4.4-kb sali segment containing the ppc gene, in both orientations. the specific activity of the enzyme was increased approx. 20-fold by these plasmids. experiments with maxicells harboring ps2 showed ...19846396163
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