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bioreactor design studies for a hydrogen-producing bacterium.carbon monoxide (co) can be metabolized by a number of microorganisms along with water to produce hydrogen (h2) and carbon dioxide. national renewable energy laboratory researchers have isolated a number of bacteria that perform this so-called water-gas shift reaction at ambient temperatures. we performed experiments to measure the rate of co conversion and h2 production in a trickle-bed reactor (tbr). the liquid recirculation rate and the reactor support material both affected the mass transfer ...200212018287
n-terminal methylation of the core light-harvesting complex in purple photosynthetic bacteria.several core light-harvesting complexes from both sulfur and non-sulfur purple photosynthetic bacteria have been identified to be methylated at the n-terminal alpha-amino group of beta-polypeptides by using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and nuclear magnetic resonance. monomethylation has been confirmed for the n-terminal alanine residues of the beta-polypeptides from rhodospirillum rubrum, thermochromatium tepidum and chromatium vinosum, but not for ...200212023037
evidence for a wide occurrence of proton-translocating pyrophosphatase genes in parasitic and free-living protozoa.proton-translocating inorganic pyrophosphatases (h(+)-ppase, ec 3.6.1.1) are integral membrane proteins that have been extensively studied in higher plants, the photosynthetic bacterium rhodospirillum rubrum and, more recently, in some human pathogenic protozoa. by using a pcr-based approach, fragments of genes coding for h(+)-ppases in a number of protists, both free-living and parasites of animals and plants, that belong to diverse taxonomic groups (trypanosomatids, ciliates, apicomplexans, eu ...200212056804
a coupling factor from rhodospirillum rubrum chromatophores. 197211946452
analysis of the l116k variant of cooa, the heme-containing co sensor, suggests the presence of an unusual heme ligand resulting in novel activity.cooa is the co-sensing transcriptional activator from rhodospirillum rubrum, in which co binding to its heme prosthetic group triggers a conformational change of cooa that allows the protein to bind its cognate target dna sequence. by a powerful in vivo screening method following the simultaneous randomization of the codons for two c-helix residues, 113 and 116, near the distal heme pocket of cooa, we have isolated a series of novel cooa variants. in vivo, these show very high co-independent act ...200212121986
[modeling of energy migration and trapping in purple bacteria. analysis of extreme formulae].homogeneous pigment ensembles similar to those of purple bacteria rhodospirillum rubrum were studied. two formulae were advanced for the limiting values of excitation lifetime and quantum yield of excitation trapping in these ensembles, provided all reaction centers are in an active state. it was demonstrated by mathematical modeling that these limiting values strictly depend on three parameters of molecular ensembles: the numbers of core-bacteriochlorophyll molecules per reaction center, the va ...200211969165
thalassospira lucentensis gen. nov., sp. nov., a new marine member of the alpha-proteobacteria.a novel bacterium from the mediterranean sea was isolated under oligotrophic conditions at in situ temperature after prolonged continuous culture. the isolates were initially characterized by partial 16s rrna gene sequencing. similarity searches of one of the isolates, qmt2t, indicated high sequence identity to the well-characterized rhodospirillum rubrum, [aquaspirillum] itersonii and [oceanospirillum] pusillum micro-organisms, which are representatives of the alpha-subclass of the proteobacter ...200212148640
a quantum chemistry study of binding carotenoids in the bacterial light-harvesting complexes.carotenoids play the dual function of light harvesting and photoprotection in photosynthetic organisms. despite their functional importance, the molecular basis for binding of carotenoids in the photosynthetic proteins is poorly understood. we have discovered that all carotenoids are surrounded either by aromatic residues or by chlorophylls in all known crystal structures of the photosynthetic pigment-protein complexes. the intermolecular pi-pi stacking interactions between carotenoids and the s ...200212105926
carbon monoxide dehydrogenase from rhodospirillum rubrum produces formate.carbon monoxide dehydrogenase (codh) from rhodospirillum rubrum reversibly catalyzes the oxidation of co to co(2) at the active site c-cluster. in this article, the reduction of co(2) to formate is reported as a slow side reaction catalyzed by both ni-containing codh and ni-deficient codh. recently, the structures of r. rubrum codh and its active site nifes cluster (the c-cluster) have been solved. the data in this manuscript describe the formate-producing capability of codh with or without ni i ...200212203017
a conformational change in the isolated nadp(h)-binding component (diii) of transhydrogenase induced by low ph: a reflection of events during proton translocation by the complete enzyme?transhydrogenase couples the reduction of nadp(+) by nadh to inward proton translocation across the bacterial (or mitochondrial) membrane. conformational changes in the nadp(h)-binding component of the enzyme (diii) are central to the coupling mechanism. in the "open" state, nadp(h) bound to diii can readily exchange with nucleotides in the solvent but hydride transfer [to/from nad(h) bound to di] is prevented. in the "occluded" state, bound nadp(h) cannot exchange with solvent nucleotides but t ...200212206884
supramolecular organisation of the photosynthetic chain in anoxygenic bacteria.this minireview summarizes our present view of the supramolecular organization of the photosynthetic apparatus of rhodobacter sphaeroides and rhodobacter capsulatus. these two species present a close association between two reaction centers (rcs), one cytochrome (cyt) bc(1) and one cyt c. in r. sphaeroides, the rcs are only partially surrounded by lh1 complexes. this open ring of lh1 complexes is required for an efficient photoinduced cyclic electron transfer only under conditions where the quin ...200212206892
spectroscopy on individual light-harvesting 1 complexes of rhodopseudomonas acidophila.in this paper the fluorescence-excitation spectra of individual lh1-rc complexes (rhodopseudomonas acidophila) at 1.2 k are presented. all spectra show a limited number of broad bands with a characteristic polarization behavior, indicating that the excitations are delocalized over a large number of pigments. a significant variation in the number of bands, their bandwidths, and polarization behavior is observed. only 30% of the spectra carry a clear signature of delocalized excited states of a ci ...200212202393
projection structure of the photosynthetic reaction centre-antenna complex of rhodospirillum rubrum at 8.5 a resolution.two-dimensional crystals of the reaction-centre-light-harvesting complex i (rc-lh1) of the purple non- sulfur bacterium rhodospirillum rubrum have been formed from detergent-solubilized and purified protein complexes. unstained samples of this intrinsic membrane protein complex have been analysed by electron cryomicroscopy (cryo em). projection maps were calculated to 8.5 a from two different crystal forms, and show a single reaction centre surrounded by 16 lh1 subunits in a ring of approximatel ...200212145194
cloning a gene encoding a light-harvesting i polypeptide from ectothiorhodospira sp.trying to detect the genes coding for light harvesting ii polypeptides of the purple bacteria ectothiorhodospira sp. a gene corresponding to a light harvesting i polypeptide was cloned. this paper discusses the probable reasons of this result. the sequence of this polypeptide underlines the strong similarity with light harvesting complexes from bacteria such as rhodospirillum molischianum and chromatium vinosum.200212240998
biochemical characterization of the dissociated forms from the core antenna proteins from purple bacteria.the core light-harvesting protein from rhodospirillum rubrum is of particular interest for studying membrane polypeptide association, as it can be reversibly dissociated in the presence of n-octyl-beta-d-glucopyranoside (betaog) into smaller subunit forms, which exhibit dramatically blue-shifted absorption properties (miller et al. (1987) biochemistry 26, 5055-5062). during this dissociation/reassociation process, two main spectroscopic forms are observed, absorbing at 820 (b820) and 777 (b777) ...200212269824
aminomethylenediphosphonate: a potent type-specific inhibitor of both plant and phototrophic bacterial h+-pyrophosphatases.the suitability of different pyrophosphate (ppi) analogs as inhibitors of the vacuolar h+-translocating inorganic pyrophosphatase (v-ppase; ec 3.6.1.1) of tonoplast vesicles isolated from etiolated hypocotyls of vigna radiata was investigated. five 1,1-diphosphonates and imidodiphosphate were tested for their effects on substrate hydrolysis by the v-ppase at a substrate concentration corresponding to the km of the enzyme. the order of inhibitory potency (apparent inhibition constants, kiapp valu ...199412232069
converting the nifes carbon monoxide dehydrogenase to a hydrogenase and a hydroxylamine reductase.substitution of one amino acid for another at the active site of an enzyme usually diminishes or eliminates the activity of the enzyme. in some cases, however, the specificity of the enzyme is changed. in this study, we report that the changing of a metal ligand at the active site of the nifes-containing carbon monoxide dehydrogenase (codh) converts the enzyme to a hydrogenase or a hydroxylamine reductase. codh with alanine substituted for cys(531) exhibits substantial uptake hydrogenase activit ...200212374822
characterization of three spiral-shaped purple nonsulfur bacteria isolated from coastal lagoon sediments, saline sulfur springs, and microbial mats: emended description of the genus roseospira and description of roseospira marina sp. nov., roseospira navarrensis sp. nov., and roseospira thiosulfatophila sp. nov.three new spirilloid phototrophic purple nonsulfur bacteria were isolated in pure culture from three different environments: strain ce2105 from a brackish lagoon in the arcachon bay (atlantic coast, france), strain se3104 from a saline sulfur spring in the pyrenees (navarra, spain), and strain at2115 a microbial mat (tetiaroa atoll, society islands). single cells of the three strains were spiral-shaped and highly motile. their intracellular photosynthetic membranes were of the vesicular type. ba ...200212375098
crystal structures of transhydrogenase domain i with and without bound nadh.transhydrogenase (th) is a dimeric integral membrane enzyme in mitochondria and prokaryotes that couples proton translocation across a membrane with hydride transfer between nad(h) and nadp(h) in soluble domains. crystal structures of the nad(h) binding alpha1 subunit (domain i) of rhodospirillum rubrum th have been determined at 1.8 a resolution in the absence of dinucleotide and at 1.9 a resolution with nadh bound. each structure contains two domain i dimers in the asymmetric unit (ab and cd); ...200212379117
inhibition of acetate and propionate assimilation by itaconate via propionyl-coa carboxylase in isocitrate lyase-negative purple bacterium rhodospirillum rubrum.itaconate is known as a potent inhibitor of isocitrate lyase. unexpectedly, itaconate was a strong inhibitor of acetate and propionate assimilation in isocitrate lyase-negative purple non-sulfur bacterium rhodospirillum rubrum. it was shown that in cell extracts of r. rubrum itaconate inhibited propionyl-coa carboxylase (pcc) activity. the participation of pcc in propionate assimilation in r. rubrum is well-documented, but the inhibition of acetate assimilation suggests that pcc is also involved ...200212423751
the role of the hydrophobic distal heme pocket of cooa in ligand sensing and response.cooa from rhodospirillum rubrum is a heme-containing transcriptional activator that becomes activated only upon binding co. the basis for this specificity has been probed in a cooa variant, termed deltap3r4 cooa, lacking two residues adjacent to the pro(2) heme ligand, which weakens that ligand. deltap3r4 cooa can bind imidazole and cn(-), as well as co, and form a 6-coordinate low spin adduct with each. however, in contrast to the case with co, imidazole and cn(-) do not stimulate the dna bindi ...200312433917
time-resolved dissociation of the light-harvesting 1 complex of rhodospirillum rubrum, studied by infrared laser temperature jump.for the first time, data are presented on the time-resolved disassembly reaction of a highly organized membrane protein complex in vitro. the photosynthetic core light-harvesting complex of the bacterial strain rhodospirillum rubrum g9 consists of 12-16 dimeric subunits that in vivo are associated with the photosynthetic reaction center in a ringlike manner. isolated in a detergent solution, its appearance either as a ringlike complex (called b873 and absorbing at 873 nm), subunit dimer (called ...200212484747
phylogenetic relationships of the helical-shaped bacteria in the alpha proteobacteria inferred from 16s rdna sequences.16s ribosomal rna gene sequences from seven strains of aquaspirillum peregrinum, aqu. itersonii, aqu. polymorphum, and oceanospirillum pusillum were compared with homologous sequences from other members of helical-shaped bacteria. the bootstrapped neighbor-joining tree, inferred from 887 aligned sites, placed the spirillum taxa assigned to aquaspirillum, oceanospirillum, azospirillum, magnetospirillum, rhodospirillum, and rhodocista of the proteobacteria in seven clusters of alpha proteobacteria ...199712501339
photosynthetic fractionation of the stable isotopes of oxygen and carbon.isotope discrimination during photosynthetic exchange of o2 and co2 was measured using enzyme, thylakoid, and whole cell preparations. evolved oxygen from isolated spinach thylakoids was isotopically identical (within analytical error) to its source water. similar results were obtained with anacystis nidulans richter and phaeodactylum tricornutum bohlin cultures purged with helium. for consumptive reactions, discrimination ([delta], where 1 + [delta]/1000 equals the isotope effect, k16/k18 or k1 ...199312231663
low-intensity pump-probe measurements on the b800 band of rhodospirillum molischianum.we have measured low-intensity, polarized one-color pump-probe traces in the b800 band of the light-harvesting complex lh2 of rhodospirillum molischianum at 77 k. the excitation/detection wavelength was tuned through the b800 band. a single-wavelength and a global target analysis of the data were performed with a model that accounts for excitation energy transfer among the b800 molecules and from b800 to b850. by including the anisotropy of the signals into the fitting procedure, both transfer p ...200312524297
identification and preliminary characterization of acsf, a putative ni-insertase used in the biosynthesis of acetyl-coa synthase from clostridium thermoaceticum.the acsabcde genes in the clostridium thermoaceticum genome are used for autotrophic acetyl-coa synthesis using the wood-ljungdahl pathway. a 2.8-kb region between acsc and acsd was cloned and sequenced. two open reading frames, orf7 (approximately 1.9 kb) and acsf (approximately 0.7 kb) were identified. orf7 appears to encode an fe-s protein, in that it contains five conserved cysteine residues, three of which are present in a motif (cggxxxcgxc) commonly used to coordinate fe-s clusters. howeve ...200312538050
repositioning about the dimer interface of the transcription regulator cooa: a major signal transduction pathway between the effector and dna-binding domains.activation of the homodimeric transcriptional regulator cooa depends on the coupling of co binding at an effector domain heme with the allosteric repositioning of the dna-binding domain f-helix that promotes specific dna interaction. by analogy to the homologous camp receptor protein (crp), it has been proposed that effector binding elicits subunit reorientation about their coiled-coil c-helix interface, and that this effector domain reorientation stabilizes the active position of the dna-bindin ...200312507482
absorption and cd spectroscopy and modeling of various lh2 complexes from purple bacteria.the absorption (od) and circular dichroism (cd) spectra of lh2 complexes from various purple bacteria have been measured and modeled. based on the lineshapes of the spectra we can sort the lh2 complexes into two distinguishable groups: "acidophila"-like (type 1) and "molischianum"-like (type 2). starting from the known geometric structures of rhodopseudomonas (rps.) acidophila and rhodospirillum (rsp.) molischianum we can model the od and cd spectra of all species by just slightly varying some k ...200211916874
spectroscopic characterisation of a tetrameric subunit form of the core antenna protein from rhodospirillum rubrum.the core light-harvesting complex (lh1) of rhodospirillum rubrum is constituted of multiple heterodimeric subunits, each containing two transmembrane polypeptides, alpha and beta. the detergent octylglucoside induces the stepwise dissociation of lh1 into b820 (an alphabeta dimer) and b777 (monomeric polypeptides), both of which still retain their bound bacteriochlorophyll molecules. we have investigated the absorption properties of b820 as a function of temperature, whereby a spectral population ...200212297309
isolation and molecular characterization of pmg160, a mobilizable cryptic plasmid from rhodobacter blasticus.a 3.4-kb cryptic plasmid was obtained from a new isolate of rhodobacter blasticus. this plasmid, designated pmg160, was mobilizable by the conjugative strain escherichia coli s17.1 into rhodobacter sphaeroides, rhodobacter capsulatus, and rhodopseudomonas palustris. it replicated in the latter strains but not in rhodospirillum rubrum, rhodocyclus gelatinosus, or bradyrhizobium species. plasmid pmg160 was stably maintained in r. sphaeroides for more than 100 generations in the absence of selectio ...200312570988
complete spectra of the far-red chemiluminescence of the oxygenase reaction of mn2+-activated ribulose-bisphosphate carboxylase/oxygenase establish excited mn2+ as the source.chemiluminescence emitted by mn(2+)-activated ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco) while catalyzing oxygenation was analyzed to clarify the source of the emission. using dual detectors capturing radiation over a wide range of visible and infrared wavelengths, we tested for radiation from singlet o(2) decay and found it to be essentially absent (less than 0.1% of the total luminescence intensity). spectra were determined between 647 and 885 nm with a very sensitive, charge-co ...200312604603
[two-level heterogenous energy migration. modeling and application to purple bacteria].the dynamics of migration of electronic excitations and the efficiency of their trapping in two-dimensional ensembles of molecules were analyzed. molecules were characterized using the following parameters: the width of long-wavelength bands, the values of extinction and rate constant of deactivation of electronic excitations, critical distances of migration close to those of dye molecules, in particular, bacteriochlorophyll a and purple bacteria. a comparative analysis of two-dimensional models ...200312630112
cd bioaccumulation by a freshwater bacterium, rhodospirillum rubrum.cd bioaccumulation by rhodospirillum rubrum, a gram-negative freshwater bacterium, was studied in a synthetic medium. the free ion (cd2+) was the best predictor of the cd internalization fluxes. representation of the short-term uptake fluxes as a function of [cd2+] in the medium demonstrated a linear relationship, as would be expected for a rate-limiting, first-order internalization with a single transporter. nonetheless, several different accumulation profiles were observed, depending on the cd ...200312636267
glutamine 132 in the nad(h)-binding component of proton-translocating transhydrogenase tethers the nucleotides before hydride transfer.transhydrogenase, found in bacterial membranes and inner mitochondrial membranes of animal cells, couples the redox reaction between nad(h) and nadp(h) to proton translocation. in this work, the invariant gln132 in the nad(h)-binding component (di) of the rhodospirillum rubrum transhydrogenase was substituted with asn (to give di.q132n). mixtures of the mutant protein and the nadp(h)-binding component (diii) of the enzyme readily produced an asymmetric complex, (di.q132n)(2)diii(1). the x-ray st ...200312564924
crystal structure of a photoactive yellow protein from a sensor histidine kinase: conformational variability and signal transduction.photoactive yellow protein (e-pyp) is a blue light photoreceptor, implicated in a negative phototactic response in ectothiorhodospira halophila, that also serves as a model for the per-arnt-sim superfamily of signaling molecules. because no biological signaling partner for e-pyp has been identified, it has not been possible to correlate any of its photocycle intermediates with a relevant signaling state. however, the pyp domain (ppr-pyp) from the sensor histidine kinase ppr in rhodospirillum cen ...200312563032
single-molecule study of the electronic couplings in a circular array of molecules: light-harvesting-2 complex from rhodospirillum molischianum.applying single-molecule spectroscopic techniques allowed us to determine the mutual angles between the transition-dipole moments associated with optical transitions of the eight bacteriochlorophyll a molecules which form the so-called b800 ring of the light-harvesting-2 complex from rhodospirillum molischianum. the orientation of the transition-dipole moment is a sensitive probe for the strength of the local intermolecular interactions because of the well-defined arrangement of the individual m ...200312570608
ni and co: more surprises. 200312660715
rhodobacter sphaeroides has a family ii pyrophosphatase: comparison with other species of photosynthetic bacteria.the cytoplasmic pyrophosphatase from rhodobacter sphaeroides was purified and characterized. the enzyme is a homodimer of 64 kda. the n-terminus was sequenced and used to obtain the complete pyrophosphatase sequence from the preliminary genome sequence of rba. sphaeroides, showing extensive sequence similarity to family ii or class c pyrophosphatases. the enzyme hydrolyzes only mg-pp(i) and mn-pp(i) with a k(m) of 0.35 mm for both substrates. it is not activated by free mg (2+), in contrast to t ...200312669192
a reaction center-light-harvesting 1 complex (rc-lh1) from a rhodospirillum rubrum mutant with altered esterifying pigments: characterization by optical spectroscopy and cryo-electron microscopy.introduction of the bchp gene from rhodobacter sphaeroides encoding geranylgeranyl reductase into rhodospirillum rubrum alters the esterification of the bacteriochlorophylls so that phytol is used instead of geranylgeraniol. the resulting transconjugant strain of rs. rubrum grows photosynthetically, showing that phytolated bchla can substitute for the native pigment in both the reaction center (rc) and the light-harvesting 1 (lh1) complexes. this genetic manipulation perturbs the native caroteno ...200312719425
activation mechanism of the co sensor cooa. mutational and resonance raman spectroscopic studies.cooa is a co-dependent heme protein transcription factor of the bacterium rhodospirillum rubrum. co binding to its heme causes cooa to bind dna and activate expression of genes for co metabolism. to understand the nature of co activation, several cooa mutational variants have been studied by resonance raman spectroscopy, in vivo activity measurements, and dna binding assays. analysis of the fe-c and c-o stretching raman spectroscopy bands permits the conclusion that when co displaces the pro2 he ...200312796503
the influence of detergents and amphiphiles on the solubility of the light-harvesting i complex.the effect of detergents and amphiphiles on protein solubility and their use in crystallization solutions was examined for an integral membrane protein, the light-harvesting i complex from rhodospirillum centenum. measurement by a centrifugation assay of the solubility of the protein in different detergents and amphiphiles showed high protein-solubility values when either octyl glucoside or lauryldimethylamine-n-oxide was present with heptanetriol or when deoxycholate was present with spermine. ...200312876344
rhodospirillum rubrum has a family i pyrophosphatase: purification, cloning, and sequencing.the cytoplasmic pyrophosphatase of the photosynthetic bacterium rhodospirillum rubrum was purified to electrophoretic homogeneity. the enzyme is a homohexamer of 20-kda monomers. the gene was cloned and sequenced. alignment of the deduced 179-amino-acid protein with known bacterial pyrophosphatases revealed conservation of all residues in the active site. attempts to obtain an insertion mutant of the cytoplasmic pyrophosphatase gene did not yield any cell completely devoid of cytoplasmic pyropho ...200312658333
modeling stability of photoheterotrophic continuous cultures in photobioreactors.continuous cultures of the purple non-sulfur bacterium rhodospirillum rubrum were grown in a cylindrical photobioreactor in photoheterotrophic conditions, using acetate as carbon source. a new kinetic and stoichiometric knowledge model was developed, and its ability to simulate experimental results obtained under varying incident light fluxes and residence times is discussed. the model accurately predicts the stable, unstable, or oscillating behavior observed for the reactor productivity. in par ...200312892484
pulsed high-frequency epr study on the location of carotenoid and chlorophyll cation radicals in photosystem ii.when the primary electron-donation pathway from the water-oxidation complex in photosystem ii (ps ii) is inhibited, chlorophyll (chl(z) and chl(d)), beta-carotene (car) and cytochrome b(559) are alternate electron donors that are believed to function in a photoprotection mechanism. previous studies have demonstrated that high-frequency epr spectroscopy (at 130 ghz), together with deuteration of ps ii, yields resolved car(+) and chl(+) epr signals (lakshmi et al. j. phys. chem. b 2000, 104, 10 44 ...200312708850
circular symmetry of the light-harvesting 1 complex from rhodospirillum rubrum is not perturbed by interaction with the reaction center.the effect of the interaction of the reaction center (rc) upon the geometrical arrangement of the bacteriochlorophyll a (bchla) pigments in the light-harvesting 1 complex (lh1) from rhodospirillum rubrum has been examined using single molecule spectroscopy. fluorescence excitation spectra at 1.8 k obtained from single detergent-solubilized as well as single membrane-reconstituted lh1-rc complexes showed predominantly (>70%) a single broad absorption maximum at 880-900 nm corresponding to the q(y ...200312950162
photosynthesis and growth of tobacco with a substituted bacterial rubisco mirror the properties of the introduced enzyme.complete replacement, by biolistic plastid transformation, of the hexadecameric ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco) of tobacco (nicotiana tabacum) with the dimeric version from the bacterium, rhodospirillum rubrum, resulted in fully autotrophic and reproductive tobacco plants that required high co(2) concentrations to grow (whitney sm, andrews tj [2001] proc natl acad sci usa 98: 14738-14743). growth and photosynthesis of these plants was compared with that of nontransforme ...200312970494
tryptophan phosphorescence spectroscopy reveals that a domain in the nad(h)-binding component (di) of transhydrogenase from rhodospirillum rubrum has an extremely rigid and conformationally homogeneous protein core.the characteristics of tryptophan phosphorescence from the nad(h)-binding component (di) component of rhodospirillum rubrum transhydrogenase are described. this enzyme couples hydride transfer between nad(h) and nadp(h) to proton translocation across a membrane and is only active as a dimer. tryptophan phosphorescence spectroscopy is a sensitive technique for the detection of protein conformational changes and was used here to characterize di under mechanistically relevant conditions. our result ...200312972415
biosynthesis of c14-labeled protein and amino acids with rhodosprillum rubrum. 195212997241
modelling continuous culture of rhodospirillum rubrum in photobioreactor under light limited conditions.rhodospirillum rubrum was grown continuously and photoheterotrophically under light limitation using a cylindrical photobioreactor in which the steady state biomass concentration was varied between 0.4 to 4 kg m(-3) at a constant radiant incident flux of 100 w m(-2). kinetic and stoichiometric models for the growth are proposed. the biomass productivities, acetate consumption rate and the co2 production rate can be quantitatively predicted to a high level of accuracy by the proposed model calcul ...200312882553
electron transport dynamics at the quinone acceptor site of bacterial photosynthetic reaction centers as probed using fast temperature changes.methods of laser-induced temperature jumps and fast freezing were used for testing the rates of thermoinduced conformational transitions of reaction center (rc) complexes in chromatophores and isolated rc preparations of various photosynthesizing purple bacteria. an electron transfer reaction from primary to secondary quinone acceptors was used as a probe of electron transport efficiency. the thermoinduced transition of the acceptor complex to the conformational state facilitating electron trans ...200312679860
studies on the metabolism of photosynthetic bacteria. xv. photoautoxidation of ferrocytochrome c in extracts of rhodospirillum rubrum. 195313058386
spirilloxanthin synthesis by resting cells of rhodospirillum rubrum. 195313058884
relative efficiency of light absorbed by carotenoids in photosynthesis and phototaxis of rhodospirillum rubrum. 195313058995
the quantitative determination of the spectral distribution of phototactic sensitivity in the purple bacterium rhodospirillum rubrum. 195313066451
the tricarboxylic acid in rhodospirillum rubrum. 195313084651
the action of monofluoroacetate on the metabolism of rhodospirillum rubrum. 195313093643
studies in carotenogenesis. 10. spirilloxanthin synthesis by washed cells of rhodospirillum rubrum. 195413140178
studies in the phototaxis of rhodospirillum rubrum. i. action spectrum, growth in green light, and weber law adherence. 195313159239
studies in the phototaxis of rhodospirillum rubrum. ii. the relation between phototaxis and photosynthesis. 195313159240
studies in the phototaxis of rhodospirillum rubrum. iii. quantitative relations between stimulus and response. 195313159241
studies on the metabolism of photosynthetic bacteria. xvii. comparative studies on simultaneous photo-oxidations in bacterial and plant extracts. 195413181467
electron microscopy of the cell walls of bacillus megaterium and rhodospirillum rubrum. 195413198902
crystalline chlorophyll and bacteriochlorophyll. 195413208298
effects of light intensity and nitrogen growth source on hydrogen metabolism in rhodospirillum rubrum. 195413216213
hematin compounds in photosynthetic bacteria. 195413221572
enzymatic activities affecting cytochromes in photosynthetic bacteria. 195413221573
comparative studies on bacterial cytochromes. 195513239624
studies in carotenogenesis. 9. general cultural conditions controlling carotenoid (spirilloxanthin) synthesis in the photosynthetic bacterium rhodospirillum rubrum. 195313032107
cytochrome c content of rhodosperillum rubrum. 195313051199
inter- and intraspecific variation in excited-state triplet energy transfer rates in reaction centers of photosynthetic bacteria.in protein-cofactor reaction center (rc) complexes of purple photosynthetic bacteria, the major role of the bound carotenoid (c) is to quench the triplet state formed on the primary electron donor (p) before its sensitization of the excited singlet state of molecular oxygen from its ground triplet state. this triplet energy is transferred from p to c via the bacteriochlorophyll monomer b(b). using time-resolved electron paramagnetic resonance (trepr), we have examined the temperature dependence ...200312945578
[cytology of rhodospirillum rubrum]. 195513303213
[electronic microscopic demonstration of the fine structure of rhodospirillum rubrum; results of a new simple thin-section method]. 195513303222
competition between light and dark metabolism in rhodospirillum rubrum. 195513249512
studies in carotenogenesis. 21. the nature of the changes in carotenoid synthesis in rhodospirillum rubrum during growth. 195613341896
the effect of monofluoroacetate on the metabolism of rhodospirillum rubrum. 195613355872
the use of radioactive carbon dioxide in the measurement of carbon dioxide fixation in rhodospirillum rubrum. 195613363851
ph-induced changes of the infrared absorption spectra of purple bacteria. 195613373840
observations on the infrared absorption spectrum of bacteriochlorophyll. 195613373841
tactic responses and metabolic activities in rhodospirillum rubrum. 195513249513
a carbon dioxide requirement for the metabolism of propionate in rhodospirillum rubrum. 195713403657
the acetate-activating mechanism in rhodospirillum rubrum. 195713412728
oxidative metabolism of propionate in rhodospirillum rubrum. 195713425574
photosynthetic metabolism of propionate in rhodospirillum rubrum. 195713425575
photosynthesis and respiration in rhodospirillum rubrum. 195513249511
the dissimilation of amino acids by rhodospirillum rubrum. 195613376866
specific inhibition of carotenoid synthesis in a photosynthetic bacterium and its physiological consequences. 195813504140
on the interplay of environmental factors affecting taxis and motility in rhodospirillum rubrum. 195813534434
some effects of ultraviolet on respiration in purple bacteria. 195813534435
investigations on bacteriochlorophyll in organic solutions. 195813535628
transamination in rhodospirillum rubrum. 195713479121
on the new heme protein of facultative photoheterotrophs. 195813502373
the path of carotenoid synthesis in a photosynthetic bacterium. 195813584349
preparation and properties of protoplasts of rhodospirillum rubrum. 195813584374
origin of the methoxyl groups in spirilloxanthin; a carotenoid synthesized by the photosynthetic bacterium rhodospirillum rubrum. 195813600303
the incorporation of amino acid carbon by rhodospirillum rubrum. 195813618262
enzymatic synthesis of sigma-aminolevulinic acid. 195813627809
a comparison of the oxidative metabolism of light and dark grown rhodospirillum rubrum. 195613329919
[brief notes on the anatomy, physiology etiopathogenesis, diagnosis & therapy of urinary incontinence due to stress in women]. 195913652419
photoreduction of pyridine nucleotides by cell-free extracts and chromatophores of rhodospirillum rubrum. 195813563472
inhibition of reduce diphosphopyridine nucleotide oxidase activity of rhodospirillum rubrum chromatophores upon illumination. 195813563473
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