Publications

crystal structure and possible dimerization of the high-potential iron-sulfur protein from chromatium purpuratum.	the crystal structure of the high-potential iron-sulfur protein (hipip) isolated from chromatium purpuratum is reported at 2.7 a resolution. the three hipip molecules in the asymmetric unit of the crystals form one and one-half dimers. two molecules are related by a noncrystallographic symmetry rotation of approximately 175 degrees with negligible translation along the dyad axis. the third molecule in the asymmetric unit also forms a dimer with a second hipip molecule across the crystallographic ...	1998	9760225
purification and characterization of chromatium vinosum groel and groes proteins overexpressed in escherichia coli cells lacking the endogenous groesl operon.	using an escherichia coli strain (rf101) in which the endogenous chromosomal groesl operon was removed, we overexpressed the groel and groes chaperonins cloned from the photosynthetic bacterium chromatium vinosum. the identities of these proteins were confirmed by immunological and n-terminal sequence analyses. the native molecular masses of groel and groes, as determined by size-exclusion chromatography, were 830 and 74 kda, respectively. this suggests a tetradecameric structure for groel and a ...	1998	9790891
acclimation of the photosynthetic response of chromatium vinosum to light-limiting conditions.	the photosynthetic response of the purple sulfur bacterium chromatium vinosum dsm 185 to different degrees of illumination was analyzed. the microorganism was grown in continuous culture, and samples were taken from the effluent of the culture and incubated at different irradiances to determine the specific rate of sulfur oxidation as a measure of the photosynthetic activity of the organism. the activities obtained were plotted as a function of the specific rate of light uptake, and for each set ...	1998	9799283
utilization of reducing power in light-limited cultures of chromatium vinosum dsm 185.	this study describes how the phototrophic organism chromatium vinosum, when grown under different degrees of light limitation, distributes the reducing power initially present in the medium as hydrogen sulfide. under all the conditions of illumination tested, sulfur was the major store of reducing power. glycogen, which was virtually absent under light limitation, accounted for 31.6% of the stored reducing power at saturating irradiances. analysis of the electron budget showed that under light-l ...	1998	9799284
basis for monomer stabilization in rhodopseudomonas palustris cytochrome c' derived from the crystal structure.	the crystal structure of an unusual monomeric cytochrome c' from rhodopseudomonas palustris (rpcp) has been determined at 2.3 a resolution. rpcp has the four-helix (helices a, b, c and d) bundle structure similar to dimeric cytochromes c'. however the amino acid composition of the surface of helices a and b in rpcp is remarkably different from that of the dimeric cytochromes c'. this surface forms the dimer interface in the latter proteins. rpcp has seven charged residues on this surface contrar ...	1998	9826513
phylogenetic relationships among the chromatiaceae, their taxonomic reclassification and description of the new genera allochromatium, halochromatium, isochromatium, marichromatium, thiococcus, thiohalocapsa and thermochromatium.	sequences of the 16s rdna from all available type strains of chromatium species have been determined and were compared to those of other chromatiaceae, a few selected ectothiorhodospiraceae and escherichia coli. the clear separation of ectothiorhodospiraceae and chromatiaceae is confirmed. most significantly the sequence comparison revealed a genetic divergence between chromatium species originated from freshwater sources and those of truly marine and halophilic nature. major phylogenetic branch ...	1998	9828415
in vitro synthesis of poly(3-hydroxybutyric acid) by using an enzymatic coenzyme a recycling system.	purified recombinant poly(hydroxyalkanoic acid), pha, synthase from chromatium vinosum was used to examine in vitro poly(3-hydroxybutyric acid) (p(3hb)) formation. in combination with purified propionyl-coenzyme a transferase of clostridium propionicum a two-enzyme in vitro p(3hb) biosynthesis system was established which allowed the synthesis of p(3hb) from free d-(-)-3-hydroxybutyric acid as substrate. the coenzyme a residue for the activation of this hydroxyacid was provided by acetyl-coenzym ...	1998	9835044
effect of modification of histidine residues on organization of the pigment--protein complexes of chromatium minutissimum	the effect of diethyl pyrocarbonate on chromatophores and isolated pigment--protein complexes of chromatium minutissimum was studied. it is shown that modification of histidine residues results in the destruction of the core antenna lhi (b880) and in a spectral shift from 850 to 830 nm in the peripheral antenna lhii (b800-850). in the purple sulfur bacterium chromatium minutissimum the pigment--protein complexes b800-b850 (peripheral antenna, lhii) and b880 (core antenna, lhi) collect and transm ...	1998	9864456
physiology and genetics of sulfur-oxidizing bacteria.	reduced inorganic sulfur compounds are oxidized by members of the domains archaea and bacteria. these compounds are used as electron donors for anaerobic phototrophic and aerobic chemotrophic growth, and are mostly oxidized to sulfate. different enzymes mediate the conversion of various reduced sulfur compounds. their physiological function in sulfur oxidation is considered (i) mostly from the biochemical characterization of the enzymatic reaction, (ii) rarely from the regulation of their format ...	1998	9328649
a new comamonas testosteroni steroid-inducible gene: cloning and sequence analysis.	comamonas testosteroni can grow on a variety of steroid compounds as the sole carbon and energy source. in a previous study, we cloned and sequenced the testosterone-inducible betahsd gene from c. testosteroni (genti-raimondi, s., tolmasky, m., patrito, l., flury, a. and actis, l., molecular cloning and expression of the beta-hydroxysteroid dehydrogenase gene from pseudomonas testosteroni. gene, 1991, 105, 43-49.). herein we report the cloning and characterization of another steroid-inducible ge ...	1997	9449210
structure and composition of freshwater microbial mats from a sulfur spring ("font pudosa", ne spain).	different types of microbial mats developing on the wall on a non-thermal sulfur freshwater spring have been studied. both, light and electron microscopy as well as hplc analysis of photosynthetic pigments revealed their structure and composition. prokaryotic chlorophylls and carotenoids helped in the taxonomical assignment of the main photosynthetic groups. "inverted position" mats (mat-i) were dominated by chromatiaceae; they were located closed to the water outlets (0.3 mm sulfide). "normal p ...	1997	9106181
the primary structure of rhodoferax fermentans high-potential iron-sulfur protein, an electron donor to the photosynthetic reaction center.	the complete amino acid sequence of rhodoferax fermentans high-potential iron-sulfur protein (hipip), which is known to be an efficient electron donor to the photosynthetic reaction center, has been determined using both n-terminal and c-terminal analyses. the sequence contains 75 residues, with 11 positive charges, 10 negative charges, and one histidine residue. the molecular mass of apo-hipip, determined by electrospray ionization mass spectrometry, is 7849.64 da. multiple sequence alignment, ...	1997	9119002
cloning and sequencing of the gene encoding the high potential iron-sulfur protein (hipip) from the purple sulfur bacterium chromatium vinosum.	the gene encoding the high potential iron-sulfur protein (hipip) of chromatium vinosum strain d (dsm 180t) was cloned from an ecori-hindiii digest of genomic dna. a nucleotide sequence of 648 bp length was determined which contained the coding region and putative promoter and termination sites. the gene codes for a 122 residue 12761 da protein. the c-terminal 85 residues are those of the previously biochemically determined sequence, whereas the n-terminal 37 residues constitute a leader peptide ...	1997	9177478
characterization of a partially unfolded high potential iron protein.	a partially unfolded state of the fe4s4-containing high potential iron-sulfur protein from chromatium vinosum has been detected and characterized by nmr spectroscopy following addition of a concentrated solution of guanidinium chloride to the native protein. this intermediate species (i) maintains the polymetallic center, (ii) exhibits a largely collapsed secondary structure, and (iii) undergoes fast cluster decomposition upon oxidation. this information is framed into the knowledge about this c ...	1997	9235975
cloning and characterization of sulfite dehydrogenase, two c-type cytochromes, and a flavoprotein of paracoccus denitrificans gb17: essential role of sulfite dehydrogenase in lithotrophic sulfur oxidation.	a 13-kb genomic region of paracoccus dentrificans gb17 is involved in lithotrophic thiosulfate oxidation. adjacent to the previously reported soxb gene (c. wodara, s. kostka, m. egert, d. p. kelly, and c. g. friedrich, j. bacteriol. 176:6188-6191, 1994), 3.7 kb were sequenced. sequence analysis revealed four additional open reading frames, soxcdef. soxc coded for a 430-amino-acid polypeptide with an mr of 47,339 that included a putative signal peptide of 40 amino acids (mr of 3,599) with a rr mo ...	1997	9260941
towards the phylogeny of aps reductases and sirohaem sulfite reductases in sulfate-reducing and sulfur-oxidizing prokaryotes.	the genes for adenosine-5'-phosphosulfate (aps) reductase, aprba, and sirohaem sulfite reductase, dsrab, from the sulfur-oxidizing phototrophic bacterium chromatium vinosum strain d (dsmz 180(t)) were cloned and sequenced. statistically significant sequence similarities and similar physicochemical properties suggest that the aprba and dsrab gene products from chr. vinosum are true homologues of their counterparts from the sulfate-reducing chemotrophic archaeon archaeoglobus fulgidus and the sulf ...	1997	9308173
biological activation of hydrogen.		1997	8990114
chromatium glycolicum sp. nov., a moderately halophilic purple sulfur bacterium that uses glycolate as substrate	from the microbial mats that develop in solar lake, a new purple sulfur bacterium was isolated. this strain (chromatium strain sl 3201) was morphologically similar to chromatium gracile and chromatium minutissimum. chromatium sl 3201 was found to be a moderate halophile with a growth range between 2 and 20% nacl (optimum 4-5% nacl) and was able to grow photo-organotrophically using glycolate and glycerol. it is the first described phototrophic sulfur bacterium able to use glycolate. according to ...	1997	9000336
insertional gene inactivation in a phototrophic sulphur bacterium: aps-reductase-deficient mutants of chromatium vinosum.	in purple sulphur bacteria of the family chromatiaceae sulphite oxidation via intermediary formation of adenylylsulphate is an enzymologically well characterized process. in contrast, the role of an alternative direct oxidation pathway via the enzyme sulphite:acceptor oxidoreductase has not been resolved. this paper reports the cloning of the genes encoding the adenylylsulphate-forming enzyme adenosine-5'-phosphosulphate (aps) reductase from chromatium vinosum strain d (dsm 180'), a representati ...	1996	9004500
cellular content of storage inclusions in purple sulfur bacteria determined by ultrathin sections.	phototrophic sulfur bacteria accumulate storage inclusions as a mechanism to adapt to several types of environmental stress. we compare the content of elemental sulfur and poly-beta-hydroxybutyrate (phb) found in cultures growing under laboratory conditions with the content found in microorganisms in natural environments. since natural communities are extremely heterogeneous in composition (they do not contain only phototrophic sulfur bacteria) and physiological state, it was not possible to app ...	1996	9018690
[poly-(3-hydroxybutyrate) granules in bacillus megaterium. isolation and analysis of associated proteins].	bacillus megaterium accumulates poly-(3-hydroxybutyrate) (phb) as a reserve material in intracellular granules. in this work we described a method for the preparation of phb granules from b. megaterium pv447 and the analysis by polyacrylamide gel electrophoresis of the associated proteins. by comparison with another species a function is proposed for some of these proteins.	1996	9026821
spectroscopic characterization of nitrosylheme in nitric oxide complexes of ferric and ferrous cytochrome c' from photosynthetic bacteria.	reactions of ferric and ferrous cytochromes c' from four photosynthetic bacteria (rhodobacter capsulatus atcc 11166, rhodopseudomonas palustris atcc 17001, rhodospirillum rubrum atcc 11170, and chromatium vinosum atcc 17899) with nitric oxide have been investigated by electronic absorption and electron paramagnetic resonance spectroscopies. the heme iron(iii) of these ferric cytochromes c' has been recently reported to be in a quantum mechanically admixed (s = 5/2, 3/2) state [fujii, s., yoshimu ...	1996	8547347
occurrence of polyhydroxyalkanoic acid granule-associated proteins related to the alcaligenes eutrophus h16 ga24 protein in other bacteria.	fifty different polyhydroxyalkanoic acid (pha)-accumulating bacterial strains were investigated for the occurrence of phasin proteins bound to pha granules and related to the ga24 protein of alcaligenes eutrophus h16, by isolating pha granules and western blot analysis of granule-associated proteins employing antibodies raised against the ga24 protein. it could be demonstrated that th pha granules of many poly(3-hydroxybutyrate)-accumulating bacteria exhibited a similar protein pattern, and a pr ...	1996	8598273
sequence evidence for strong conservation of the photoactive yellow proteins from the halophilic phototrophic bacteria chromatium salexigens and rhodospirillum salexigens.	the photoactive yellow proteins (pyp) have been found to date only in three species of halophilic purple phototrophic bacteria. they have photochemical activity remarkably similar to that of the bacteria rhodopsins. in contrast to rhodopsins, however, the pyps are small water-soluble proteins. we now report the complete amino acid sequences of rhodospirillum salexigens and chromatium salexigens pyp which allow comparison with the known sequence and three-dimensional structure of the prototypic p ...	1996	8611556
a high-potential soluble cytochrome c-551 from the purple phototrophic bacterium chromatium vinosum is homologous to cytochrome c8 from denitrifying pseudomonads.	a minor cytochrome c-551 component of chromatium vinosum was previously found to efficiently couple electron transfer between the cytochrome bc1 complex and the photosynthetic reaction center. we have now determined the amino acid sequence of this cytochrome c-551 and find that it is homologous to cytochrome c8 (formerly called pseudomonas cytochrome c-551). it is most similar to methylophilus methylotrophus, rhodocyclus tenuis, and azotobacter vinelandii cytochromes c8 (respectively, 57%, 52% a ...	1996	8612646
three-dimensional structure of the reduced c77s mutant of the chromatium vinosum high-potential iron-sulfur protein through nuclear magnetic resonance: comparison with the solution structure of the wild-type protein.	the full 1h nmr assignment of the reduced c77s mutant of chromatium vinosum high-potential iron-sulfur protein (hipip) was achieved by taking advantage of the assignment available for the wild-type protein. a total of 1565 nuclear overhauser effect (noe) spectroscopy cross peaks were integrated and converted into distance constraints, of which 497 were found to be irrelevant. an additional 24 dipolar constraints were obtained from one-dimensional noe difference spectra by saturating hyperfine-sh ...	1996	8639555
similarities in the architecture of the active sites of ni-hydrogenases and fe-hydrogenases detected by means of infrared spectroscopy.	three groups that absorb in the 2100-1800-cm-1 infrared spectral region have recently been detected in ni-hydrogenase from chromatium vinosum [bagley, k.a., duin, e.c., roseboom, w., albracht, s. p.j. & woodruff, w.h. (1995) biochemistry 34, 5527-5535]. to assess the significance and generality of this observation, we have carried out an infrared-spectroscopic study of eight hydrogenases of three different types (nickel, iron and metal-free) and of 11 other iron-sulfur and/or nickel proteins. in ...	1996	8647106
isolation and characterization of soluble electron transfer proteins from chromatium purpuratum.	several soluble electron transfer proteins were isolated and characterized from the marine purple-sulfur bacterium chromatium purpuratum. the c. purpuratum flavocytochrome c is similar in molecular mass (68 kda) and isoelectric point (6.5) to flavocytochromes isolated from other phototrophs. redox titrations of the flavocytochrome c hemes show two components with midpoint potential values of +15 and -120 mv, behavior similar to that observed with the flavocytochrome isolated from the thermophili ...	1996	8672482
high-resolution crystal structures of two polymorphs of cytochrome c' from the purple phototrophic bacterium rhodobacter capsulatus.	the structures of two polymorphs of cytochrome c' from rhodobacter capsulatus (rccp) strain m110 have been determined by the molecular replacement method. iron anomalous scattering data were used to confirm the molecular replacement solution. the structures were refined at 1.72 angstrom and 2.0 angstrom resolution to r-values of 15.0% and 16.3%, respectively. the rccp molecule is a dimer and each of the identical 129 residue subunits folds as a four-helical bundle with a covalently bound heme gr ...	1996	8676382
glutathione amide and its perthiol in anaerobic sulfur bacteria.	chromatium species produced the novel biological thiol glutathione amide, gamma-l-glutamyl-l-cysteinylglycine amide (gash), when grown photoheterotrophically. gash was largely converted to the corresponding perthiol during photoautotrophic growth on sulfide, suggesting that gash may have a function in anaerobic sulfide metabolism. this unprecedented form of glutathione metabolism was probably present in anaerobic ancestors of modern cyanobacteria and purple bacteria.	1996	8755912
hydrogen-bond interactions of the primary donor of the photosynthetic purple sulfur bacterium chromatium tepidum.	we have used near-infrared fourier transform (pre)resonance raman spectroscopy to determine the protein interactions with the bacteriochlorophyll (bchl) dimer constituting the primary electron donor, p, in the reaction center (rc) from the thermophilic purple sulfur bacterium chromatium tepidum. in addition, we report the alignment of partial sequences of the l and m protein subunits of c. tepidum rcs in the vicinity of the primary donor with those of rhodobacter sphaeroides and rhodopseudomonas ...	1996	8756709
molecular cloning and expression of the gene encoding chromatium vinosum 2[4fe-4s] ferredoxin.	the gene encoding chromatium vinosum 2[4fe-4s] ferredoxin has been cloned and expressed in escherichia coli. it is flanked by a gene starting with the rare codon uug and homologous to e. coli kdtb. chromatium vinosum ferredoxin may represent a new sub-class of iron-sulfur proteins widely distributed among diverse, including non-photosynthetic, bacteria.	1996	8765743
factors influencing redox thermodynamics and electron self-exchange for the [fe4s4] cluster in chromatium vinosum high potential iron protein: the role of core aromatic residues in defining cluster redox chemistry.	the roles of aromatic core residues in regulating the reduction potential, the enthalpy and entropy of reduction, and the self-exchange rate constants for electron-transfer reactions for the prosthetic [fe4s4]3+/2+ cluster of chromatium vinosum high potential iron protein (hipip) have been addressed by a combination of site-directed mutagenesis, high field nmr (exsy) experiments, and variable temperature spectrochemical redox titration measurements. minimal changes are observed following noncons ...	1996	8823183
the phylogenetic position and ultrastructure of the uncultured bacterium achromatium oxaliferum.	achromatium oxaliferum is a large, morphologically conspicuous, sediment-dwelling bacterium. nothing is known concerning its phylogeny and it has eluded all attempts at laboratory cultivation. the limited physiological description of a. oxaliferum has been based on morphological features of the bacterium such as the presence of intracellular sulphur inclusions. a. oxaliferum cells were purified from a wetland region close to rydal water (cumbria, uk). scanning and transmission electron microscop ...	1996	8828202
use of 1h longitudinal relaxation times in the solution structure of paramagnetic proteins. application to [4fe-4s] proteins.	the accuracy of the solution structures determined by nmr is often poor around paramagnetic centers because the properties of the near protons are strongly perturbed by the electronic spin. the structural information contained in the relaxation rates of these protons has been extracted here by measuring the longitudinal relaxation times with the inversion-recovery total correlation spectroscopy (ir-tocsy) sequence based on the recovery of cross peaks. in addition to measurements with nonselectiv ...	1996	8841114
high degree of similarity between chromatium vinosum and chromatium minutissimum as revealed by riboprinting.	the riboprinting technique (restriction fragment length polymorphism [rflp] analysis of pcr-amplified ribosomal dna) was used to study five strains representing three species of the genus chromatium. an rflp analysis following digestion of the amplified small-subunit ribosomal dna with 25 restriction enzymes revealed that the patterns obtained for all strains of chromatium vinosum were identical. chromatium gracile was different from c. vinosum with seven enzymes. on the other hand, chromatium m ...	1996	8863418
covalent structure of the flavoprotein subunit of the flavocytochrome c: sulfide dehydrogenase from the purple phototrophic bacterium chromatium vinosum.	the amino acid sequence of the flavoprotein subunit of chromatium vinosum flavocytochrome c-sulfide dehydrogenase (fcsd) was determined by automated edman degradation and mass spectrometry in conjunction with the three-dimensional structure determination (chen z et al., 1994, science 266:430-432). the sequence of the diheme cytochrome c subunit was determined previously. the flavoprotein contains 401 residues and has a calculated protein mass, including fad, of 43,568 da, compared with a mass of ...	1996	8880899
crystal structure of the 2[4fe-4s] ferredoxin from chromatium vinosum: evolutionary and mechanistic inferences for [3/4fe-4s] ferredoxins.	the crystal structure of the 2[4fe-4s] ferredoxin from chromatium vinosum has been solved by molecular replacement using data recorded with synchrotron radiation. the crystals were hexagonal prisms that showed a strong tendency to develop into long tubes. the hexagonal prisms diffracted to 2.1 a resolution at best, and a structural model for c. vinosum ferredoxin has been built with a final r of 19.2%. the n-terminal domain coordinates the two [4fe-4s] clusters in a fold that is almost identical ...	1996	8880900
characterization of an autoreduction pathway for the [fe4s4]3+ cluster of mutant chromatium vinosum high-potential iron proteins. site-directed mutagenesis studies to probe the role of phenylalanine 66 in defining the stability of the [fe4s4] center provide evidence for oxidative degradation via a [fe3s4] cluster.	a number of point mutations of the conserved aromatic residue phenylalanine 66 (phe66tyr, -asn, -cys, -ser) in chromatium vinosum high-potential iron sulfur protein have been examined with the aim of understanding the functional role of this residue. nonconservative replacements with polar residues have a minimal effect on the midpoint potential of the [fe4s4]3+/2+ cluster, typically < +25 mv, with a maximum change of +40 mv for phe66asn. with the exception of the phe66tyr mutant, the oxidized s ...	1996	8931551
structural origins of redox potentials in fe-s proteins: electrostatic potentials of crystal structures.	redox potentials often differ dramatically for homologous proteins that have identical redox centers. for two types of iron-sulfur proteins, the rubredoxins and the high-potential iron-sulfur proteins (hipips), no structural explanations for these differences have been found. we calculated the classical electrostatic potential at the redox site using static crystal structures of four rubredoxins and four hipips to identify important structural determinants of their redox potentials. the contribu ...	1996	8968568
evaluation of solvent accessibility to the [fe(4)s(4)] binding pocket in native and tyr19 mutant high potential iron proteins by (1)h-(15)n hmqc and (19)f nmr experiments.	the solvent accessibility of chromatium vinosumhigh potential iron protein (hipip) has been investigated by use of (1)h-(15)n hmqc, and (19)f nmr spectroscopy. these nmr experiments indicate that solvent accessibility to the cluster core is similar, and minimal, for the reduced and oxidized states of native hipip, but increases significantly for mutant proteins (tyr19leu and tyr19his). these results support a proposed role [agarwal, a.; li, d.; cowan, j. a. proc. natl. acad. sci. u.s.a. 1995, 92 ...	1996	11666298
occurrence and purification of the photoactive yellow protein of ectothiorhodospira halophila (pyp) and of immunologically related proteins of rhodospirillum salexigens and chromatium salexigens and intracellular localization of pyp.	the photoactive yellow protein of ectothiohodospira halophila (pyp) was purified to homogeneity by an advanced method and applied as an affinity ligand for the isolation of an anti-pyp igg fraction which was used for immunoscreening. the distribution of proteins immunologically related to pyp was investigated in protein fractions of 51 strains from 38 species of non-halophilic and halophilic phototrophic and chemotrophic eubacteria and archaeobacteria. strong immunoreactive bands indicating the ...	1995	8519800
presence of chromatium vinosum chaperonins 10 and 60 in mitochondria and peroxisomes of rat hepatocytes.	in the present study we report the occurrence of chaperonins, cpn10 and cpn60, in chromatium vinosum and rat hepatocytes, using specific polyclonal antibodies in conjunction with the protein a-gold immunocytochemical technique. as demonstrated by quantitative evaluations, the immunolabeling for cpn10 and cpn60 in c vinosum cells was associated primarily with the bacterial cell envelope. in rat liver homogenates, western immunoblotting analysis has shown that antibodies to cpn10 from c vinosum re ...	1995	8882520
bacteriolytic activities of the free-living soil amoebae, acanthamoeba castellanii, acanthamoeba polyphaga and hartmannella vermiformis.	bacteriolytic activities of axenically grown free-living soil amoebae acanthamoeba castellanii, acanthamoeba polyphaga and hartmannella vermiformis towards various gram-positive and gram-negative bacteria were determined. a spectrophotometric assay revealed that the specific bacteriolytic activities of both acanthamoeba species were higher as those of the three hartmannella strains. bacillus megaterium, bacillus subtilis, chromatium vinosum, micrococcus luteus and pseudomonas fluorescens were mo ...	1995	8572682
molecular genetic analysis of a thioredoxin gene from thiobacillus ferrooxidans.	the thiobacillus ferrooxidans thioredoxin gene, trxa, was isolated by its ability to complement an escherichia coli gsha trxa mutant which was otherwise unable to grow on minimal medium lacking glutathione. the t. ferrooxidans thioredoxin also enabled the in vivo reduction by e. coli of methionine sulfoxide to methionine, as well as the in vitro reduction of insulin. when present in e. coli, the t. ferrooxidans thioredoxin supported the replication of phage t7, but not the growth of phage m13. t ...	1995	7496529
nmr of chromatium vinosum ferredoxin: evidence for structural inequivalence and impeded electron transfer between the two [4fe-4s] clusters.	the 2[4fe-4s] ferredoxin from chromatium vinosum has been investigated by 1h and 13c nuclear magnetic resonance. 1h nmr sequence-specific assignments have been obtained for a large majority of the residues. they indicate that the protein folds along a pattern similar to that previously evidenced for shorter 2[4fe-4s] ferredoxins. however, c. vinosum ferredoxin differs from other ferredoxins by the occurrence of a turn in an eight amino acid region separating two successive cysteines, cys-40 and ...	1995	7819196
the three-dimensional solution structure of the reduced high-potential iron-sulfur protein from chromatium vinosum through nmr.	the 1h nmr assignment of the reduced hipip from chromatium vinosum available in the literature [gaillard, j., albrand, j.-p., moulis, j.-m., & wemmer, d. e. (1992) biochemistry 31, 5632-5639] has been extended up to 85% of the total protein protons. ninety percent of the nitrogens have been assigned. then the solution structure has been obtained using as many as 1147 meaningful noe connectivities. the protein is sizably paramagnetic even though the ground state is a singlet. nevertheless, the fi ...	1995	7819198
characterization of an acetyl-coa c-acetyltransferase (thiolase) gene from clostridium acetobutylicum atcc 824.	thiolase (thl) is an important enzyme at the junction in the pathway leading to the production of either acids (acetate or butyrate) or solvents (acetone, butanol or ethanol) during the growth of clostridium acetobutylicum atcc 824. cloning and expression of the thl-encoding gene (thl) has been described [petersen and bennett, appl. environ. microbiol. 57 (1991) 2735-2741], as has the purification and properties of the enzyme [wiesenborn et al., appl. environ. microbiol. 54 (1988) 2717-2722]. he ...	1995	7867955
rp-phosphorothioate modifications in rnase p rna that interfere with trna binding.	we have used rp-phosphorothioate modifications and a binding interference assay to analyse the role of phosphate oxygens in trna recognition by escherichia coli ribonuclease p (rnase p) rna. total (100%) rp-phosphorothioate modification at a, c or g positions of rnase p rna strongly impaired trna binding and pre-trna processing, while effects were less pronounced at u positions. partially modified e. coli rnase p rnas were separated into trna binding and non-binding fractions by gel retardation. ...	1995	7540978
role of aromatic residues in stabilization of the [fe4s4] cluster in high-potential iron proteins (hipips): physical characterization and stability studies of tyr-19 mutants of chromatium vinosum hipip.	the functional role of residue tyr-19 of chromatium vinosum hipip has been evaluated by site-directed mutagenesis experiments. the stability of the [fe4s4] cluster prosthetic center is sensitive to side-chain replacements. polar residues result in significant instability, while nonpolar residues (especially with aromatic side chains) maintain cluster stability. two-dimensional nmr data of native and mutant hipips are consistent with a model where tyr-19 serves to preserve the structural rigidity ...	1995	7568150
isolation and characterization of sulfur globule proteins from chromatium vinosum and thiocapsa roseopersicina.	purple sulfur bacteria store sulfur as intracellular globules enclosed by a protein envelope. the proteins associated with sulfur globules of chromatium vinosum and thiocapsa roseopersicina were isolated by extraction into 50% aqueous acetonitrile containing 1% trifluoroacetic acid and 10 mm dithiothreitol. the extracted proteins were separated by reversed-phase hplc, revealing three major proteins from c. vinosum and two from t. roseopersicina. all of these proteins have similar, rather unusual ...	1995	7575095
15n resonance assignments of oxidized and reduced chromatium vinosum high-potential iron protein.	the 15n resonances in reduced and oxidized chromatium vinosum high-potential iron protein have been assigned by use of 1h-1h cosy spectra and 1h-15n hmqc. hmqc-cosy, and hmqc-noesy spectra. unambiguous assignment of 70 of 85 backbone 15n resonances in the reduced protein and 62 of 85 resonances in the oxidized protein are made, as are 12 of 21 side-chain 15n resonances.	1995	7576079
influence of charge and polarity on the redox potentials of high-potential iron-sulfur proteins: evidence for the existence of two groups.	we have investigated the hipips from ectothiorhodospira vacuolata (iso-1 and iso-2), chromatium vinosum, rhodocyclus gelatinosus, rhodocyclus tenuis (strain 2761), rhodopila globiformis, and rhodospirillum salinarum (iso-2) by direct electrochemistry. using a glassy carbon electrode with a negatively charged surface, direct, unpromoted electrochemistry is possible with the positively charged hipips. with the negatively charged hipips, the positively charged and flexible bridging promoter poly(l- ...	1995	7578075
molecular cloning and sequencing of cytochrome c' from the phototrophic purple sulfur bacterium chromatium vinosum.	the gene for cytochrome c' from chromatium vinosum was cloned from a hindiii-sali digest of genomic dna. a 1.4 kbp fragment containing the gene was sequenced in both directions using the sanger dideoxy method. the cytochrome c' gene codes for a 154-residue peptide, of which the last 131 amino acids match the previously determined sequence of the protein. the remaining 23 residues represent a signal sequence that is cleaved from the polypeptide upon translocation to the periplasmic space. an addi ...	1995	7578212
three-dimensional solution structure of the oxidized high potential iron-sulfur protein from chromatium vinosum through nmr. comparative analysis with the solution structure of the reduced species.	the nmr solution structure of the oxidized hipip from chromatium vinosum has been solved. despite the fact that the protein is paramagnetic, 85% of the 1h and 80% of the 15n signals have been assigned. through 1537 noes, out of which 1142 were found to be relevant for the structure determination, a family of structures has been obtained by distance geometry calculations. these structures have then been subjected to restrained energy minimization (rem) and restrained molecular dynamics (rmd) calc ...	1995	7632685
characterization of the dynamic properties of rhodobacter capsulatus ferricytochrome c'--a 28 kda paramagnetic heme protein.	the cytochrome c' are paramagnetic heme proteins generally consisting of two identical 14 kda subunits. the recent assignment of the 1h and 15n resonances of the rhodobacter capsulatus ferricytochrome c' has allowed characterization of the dynamic properties by measurement of the heteronuclear noe for each resolved amide group. the relative importance of fast local motion and paramagnetic effect on nuclear relaxation were distinguished by comparison of the measured heteronuclear noe with that of ...	1995	7635212
partial sequence of ribulose-1,5-bisphosphate carboxylase/oxygenase and the phylogeny of prochloron and prochlorococcus (prochlorales).	the prochlorophytes, oxygenic photosynthetic prokaryotes having no phycobiliprotein but possessing chlorophylls a and b, have been proposed to have a common ancestry with green chloroplasts, yet this is still controversal. we report here that partial sequence comparisons of the large subunit of ribulose-1,5'-bisphosphate carboxylase/oxygenase, including sequence data from two prochlorophytes, prochlorococcus and prochloron, indicate that prochlorococcus is more closely related to a photosyntheti ...	1995	7643418
electron paramagnetic resonance studies of ferric cytochrome c' from photosynthetic bacteria.	electronic ground nature of ferric cytochromes c' isolated from five photosynthetic bacteria. chromatium vinosum atcc 17899, rhodobacter capsulatus atcc 11166, rhodopseudomonas palustris atcc 17001, rhodospirillum molischianum atcc 14031, and rhodospirillum rubrum atcc 11170 has been investigated by electron paramagnetic resonance (epr) spectroscopy. epr spectra indicate that the electronic ground state of five ferric cytochromes c' is a quantum mechanical admixed-spin state of a high spin (s = ...	1995	7669805
infrared-detectable groups sense changes in charge density on the nickel center in hydrogenase from chromatium vinosum.	fourier transform infrared studies of nickel hydrogenase from chromatium vinosum reveal the presence of a set of three absorption bands in the 2100-1900 cm-1 spectral region. these bands, which do not arise from carbon monoxide, have line widths and intensities rivaling those of a band arising from the carbon monoxide stretching frequency (v(co)) in the ni(ii).co species of this enzyme [bagley, k. a., van garderen, c. j., chen, m., duin, e. c., albracht, s. p. j., & woodruff, w. h. (1994) bioche ...	1995	7727413
the structure of flavocytochrome c sulfide dehydrogenase from a purple phototrophic bacterium.	the structure of the heterodimeric flavocytochrome c sulfide dehydrogenase from chromatium vinosum was determined at a resolution of 2.53 angstroms. it contains a glutathione reductase-like flavin-binding subunit and a diheme cytochrome subunit. the diheme cytochrome folds as two domains, each resembling mitochondrial cytochrome c, and has an unusual interpropionic acid linkage joining the two heme groups in the interior of the subunit. the active site of the flavoprotein subunit contains a cata ...	1994	7939681
purification and characterization of the poly(hydroxyalkanoic acid) synthase from chromatium vinosum and localization of the enzyme at the surface of poly(hydroxyalkanoic acid) granules.	a recombinant strain of escherichia coli, which overexpressed phac and phae from chromatium vinosum, was used to isolate poly(3-hydroxyalkanoic acid) synthase. the isolation was performed by a two-step procedure including chromatography on deae-sephacel and procion blue h-erd. the poly(3-hydroxyalkanoic acid) synthase consisted of two different kinds of subunit (phac, m(r) 39,500 and phae, m(r) 40.500). phac was separated from the poly(3-hydroxyalkanoic acid) synthase complex by chromatography o ...	1994	7957260
characterization of flavocytochrome c552 from the thermophilic photosynthetic bacterium chromatium tepidum.	a m(r) 68 kda flavocytochrome c552 has been isolated from the thermophilic photosynthetic purple sulfur bacterium chromatium tepidum and shown to consist of a m(r) 25 kda subunit that contains two covalently bound heme c and a m(r) 43 kda subunit that probably contains a single fad. the prosthetic group content, absorbance spectra, and subunit composition of the c. tepidum flavocytochrome are quite similar to those previously reported for the flavocytochrome c552 isolated from a mesophilic chrom ...	1994	7986066
susceptibility of various purple and green sulfur bacteria to different antimicrobial agents.	several purple and green sulfur bacteria (genera chromatium, thiocapsa and chlorobium) were tested for their sensitivity to different antimicrobial agents by a disc diffusion assay, using thioacetamide as a source of hydrogen sulfide for plate growth. chlorobium limicola strains were more sensitive to amoxicillin, erythromycin and nalidixic acid, whereas gentamicin and netilmicin were more active against the purple bacteria tested. none of the organisms were sensitive to oxacillin and trimethopr ...	1994	7988896
the photoactive yellow protein from ectothiorhodospira halophila as studied with a highly specific polyclonal antiserum: (intra)cellular localization, regulation of expression, and taxonomic distribution of cross-reacting proteins.	a rabbit antiserum was raised against the photoactive yellow protein (pyp) from ectothiorhodospira halophila and purified by adsorption experiments to obtain a highly specific polyclonal antiserum. this antiserum was used to obtain the following results. (i) in e. halophila, pyp can be isolated from the fraction of soluble proteins. in the intact cell, however, pyp appeared to be associated with (intra)cytoplasmic membranes, as was concluded from analysis of immunogold-labelled thin sections of ...	1994	8021174
preliminary x-ray crystallographic studies of photosynthetic reaction center from a thermophilic sulfur bacterium, chromatium tepidum.	a membrane protein complex, photosynthetic reaction center purified from the thermophilic purple sulfur bacterium, chromatium tepidum has been crystallized from a phosphate buffer containing a detergent, n-octyl-beta-d-glucopyranoside and a precipitant, polyethylene glycol 4000. the crystals diffracted x-rays beyond 3a resolution with synchrotron radiation and are suitable for high-resolution x-ray crystallographic studies. the crystals belong to the orthorhombic space group p2(1)2(1)2(1) with u ...	1994	8034032
infrared studies on the interaction of carbon monoxide with divalent nickel in hydrogenase from chromatium vinosum.	infrared spectra of a carbon monoxy-bound form of the epr silent ni(ii) species of hydrogenase isolated from chromatium vinosum are presented. these spectra show a band at 2060 cm-1 due to v(co) for a metal-co complex. this absorbance shifts to 2017 cm-1 upon exposure of the enzyme to 13co. this band is attributed to v(co) from a ni(ii)-co species. it is shown that the co on this species is photolabile at cryogenic temperatures but rebinds to form the original carbon monoxy species at temperatur ...	1994	8049224
phylogenetic analysis of sequences from diverse bacteria with homology to the escherichia coli rho gene.	genes from pseudomonas fluorescens, chromatium vinosum, micrococcus luteus, deinococcus radiodurans, and thermotoga maritima with homology to the escherichia coli rho gene were cloned and sequenced, and their sequences were compared with other available sequences. the species for all of the compared sequences are members of five bacterial phyla, including thermotogales, the most deeply diverged phylum. this suggests that a rho-like gene is ubiquitous in the bacteria and was present in their comm ...	1994	8051015
calculation of the redox potentials of iron-sulfur proteins: the 2-/3-couple of [fe4s*4cys4] clusters in peptococcus aerogenes ferredoxin, azotobacter vinelandii ferredoxin i, and chromatium vinosum high-potential iron protein.	calculations of the redox potentials of the 2-/3-couples of [fe4s*4cys4] clusters in the iron-sulfur proteins peptococcus aerogenes ferredoxin (pafd), azotobacter vinelandii ferredoxin i (avfdi) and chromatium vinosum high potential iron protein (cvhipip) based on the protein dipoles langevin dipoles (pdld) method are reported. the structures of these proteins have been determined by x-ray crystallography; in the case of pafd the structure has recently been revised due to a change in the sequenc ...	1994	8086408
purification and characterization of the peripheral antenna of the purple-sulfur bacterium chromatium purpuratum: evidence of an unusual pigment-protein composition.	the purification and characterization of the peripheral antenna and the preliminary characterization of a carotenoid-protein complex from the purple-sulfur bacterium chromatium purpuratum are described. the peripheral antenna of c. purpuratum is unusual among purple bacteria in that it can be resolved by sds-page into six subunits, the largest number observed thus far for a spectrally pure antenna complex. n-terminal sequence analyses of these subunits suggest that they may have an additional ba ...	1994	8117674
molecular structure of the oxidized high-potential iron-sulfur protein isolated from ectothiorhodospira vacuolata.	the high-potential iron-sulfur protein (iso-form ii) isolated from ectothiorhodospira vacuolata has been crystallized and its three-dimensional structure determined by molecular replacement procedures and refined to 1.8-a resolution with a crystallographic r factor of 16.3%. crystals employed in the investigation belonged to the space group c222(1) with unit cell dimensions of a = 58.4 a, b = 64.7 a, and c = 39.3 a and one molecule per asymmetric unit. like those hipips structurally characterize ...	1994	8117708
spectroscopic characterization of flavocytochrome c-552 from the photosynthetic purple sulfur bacterium chromatium vinosum.	the identities of the axial ligands to the two hemes of the flavocytochrome c-552 isolated from the photosynthetic purple sulfur bacterium chromatium vinosum have been investigated by visible/near-infrared absorption and magnetic circular dichroism (mcd) spectroscopies, with parallel electron paramagnetic resonance (epr) studies. one of the hemes has histidine and methionine as axial ligands and has a local environment that is relatively insensitive to the composition of the bulk medium. the sec ...	1994	8130252
further characterization of the spin coupling observed in oxidized hydrogenase from chromatium vinosum. a mössbauer and multifrequency epr study.	hydrogenase from chromatium vinosum contains 1 ni, 11-12 fe, and ca. 9 sulfides. epr and mössbauer studies of the enzyme prepared in four different oxidation states show that the enzyme contains two fe4s4 and one fe3s4 cluster. in the oxidized (2+) state, the mössbauer parameters of the two fe4s4 clusters are typical for this cluster type. upon reduction, however, these clusters do not exhibit the familiar g = 1.94 signal. the unusual nature of the reduced clusters is also borne out by the mössb ...	1994	8161560
biochemical and spectroscopic characterization of the reaction center-lh1 complex and the carotenoid-containing b820 subunit of chromatium purpuratum.	two complexes, the reaction center light-harvesting complex 1 (rc-lh1) and the b820 subunit of the lh1, have been isolated and characterized from the purple-sulfur photosynthetic bacterium chromatium purpuratum. the rc-lh1 consists of the b870 antenna and a p-870 rc with an associated tetraheme cytochrome. this complex can be further fractionated to yield the b820 subunit of the lh1. the c. purpuratum b820 subunit is the first isolated from a purple-sulfur bacterium. it is also the first that re ...	1994	8167136
anaerobic bacteria from hypersaline environments.	strictly anaerobic halophiles, namely fermentative, sulfate-reducing, homoacetogenic, phototrophic, and methanogenic bacteria are involved in the oxidation of organic carbon in hypersaline environments. to date, six anaerobic fermentative genera, containing nine species, have been described. two of them are homoacetogens. six species belong to the family haloanaerobiaceae, as indicated by their unique 16s rrna oligonucleotide sequences. desulfohalobium retbaense and desulfovibrio halophilus repr ...	1994	8177169
phylogenetic comparative chemical footprint analysis of the interaction between ribonuclease p rna and trna.	ribonuclease p rna is the catalytic moiety of the ribonucleoprotein enzyme that endonucleolytically cleaves precursor sequences from the 5' ends of pre-trnas. the bacterial rnase p rna-trna complex was examined with a footprinting approach, utilizing chemical modification to determine rnase p rna nucleotides that potentially contact trna. rnase p rna was modified with dimethylsulfate or kethoxal in the presence or absence of trna, and sites of modification were detected by primer extension. comp ...	1994	7521296
anaerobic oxidation of ferrous iron by purple bacteria, a new type of phototrophic metabolism.	anoxic iron-rich sediment samples that had been stored in the light showed development of brown, rusty patches. subcultures in defined mineral media with ferrous iron (10 mmol/liter, mostly precipitated as feco3) yielded enrichments of anoxygenic phototrophic bacteria which used ferrous iron as the sole electron donor for photosynthesis. two different types of purple bacteria, represented by strains l7 and sw2, were isolated which oxidized colorless ferrous iron under anoxic conditions in the li ...	1994	7811087
synthesis, cloning and expression of a synthetic gene for high potential iron protein from chromatium vinosum.	a synthetic gene encoding the peptide sequence for the low molecular weight (m(r) approximately 9600 da) high-potential iron protein (hipip) from the photosynthetic bacterium chromatium vinosum has been constructed by shotgun ligation of twelve complimentary oligonucleotides varying in size from 42-mers to 48-mers. after cloning the gene into a pet-21d(+) vector, expression of holoprotein in yields of 35 mg/liter of culture was obtained following induction with isopropyl-beta-d-thiogalactoside ( ...	1993	7916611
lead-catalyzed cleavage of ribonuclease p rna as a probe for integrity of tertiary structure.	pb(2+)-catalyzed cleavage of rna has been shown previously to be a useful probe for tertiary structure. in the present study, pb2+ cleavage patterns were identified for ribonuclease p rnas from three phylogenetically disparate organisms, escherichia coli, chromatium vinosum, bacillus subtilis, and for e. coli rnase p rnas that had been altered by deletions. each of the native rnas undergoes cleavage at several sites in the core structure that is common to all bacterial rnase p rnas. all the clea ...	1993	7507234
atomic structure of a cytochrome c' with an unusual ligand-controlled dimer dissociation at 1.8 a resolution.	the crystallographic structure of cytochrome c' from the purple phototrophic bacterium chromatium vinosum (cvcp) has been determined at 1.8 a resolution using multiple isomorphous replacement. the molecule is a dimer, with each 131-residue chain folding as a four-helical bundle incorporating a covalently bound heme group at the core. this structure is the third of the ubiquitous cytochromes c' to be solved and is similar to the known structures of cytochrome c' from r. molischianum (rmcp) and r. ...	1993	8230224
picosecond dynamics of excitations in light-harvesting complex b800-850 from chromatium minutissimum studied using fluorescence spectrochronography.	the picosecond dynamics of excitations in the isolated b800-850 light-harvesting complex of the purple sulfur bacterium chromatium minutissimum has been studied using picosecond fluorescence spectrochronography. a short-lived component of about 20 ps lifetime has been found at 77k at the short wavelength part of the b850 fluorescence spectrum similar to that previously described for the core antenna bacteriochlorophyll band b880 of rhodospirillum rubrum. evidence has been presented indicating th ...	1993	8335097
arhodomonas aquaeolei gen. nov., sp. nov., an aerobic, halophilic bacterium isolated from a subterranean brine.	arhodomonas aquaeolei gen. nov., sp. nov., isolated from a petroleum reservoir production fluid, is described. the single isolate was an obligately halophilic, aerobic, gram-negative, oval rod-shaped bacterium that was actively motile by means of a single polar flagellum. it was catalase and oxidase positive. the isolate had a specific requirement for nacl; growth occurred at nacl concentrations between 6 and 20%, and optimal growth occurred in the presence of 15% nacl. this species metabolized ...	1993	8347510
amplification of ribulose biphosphate carboxylase/oxygenase large subunit (rubisco lsu) gene fragments from thiobacillus ferrooxidans and a moderate thermophile using polymerase chain reaction.	southern blot analysis of dna from an iron-oxidising moderate thermophile nmw-6 and from thiobacillus ferrooxidans strain tfi-35 demonstrated sequences homologous to the rubisco lsu gene of synechococcus. dna fragments (457 bp) encoding part of the rubisco lsu gene (amino acids 73-200) were amplified from the genomic dna of thiobacillus ferrooxidans and the moderate thermophile nmw-6 using the polymerase chain reaction (pcr) technique (saiki et al. (1985) science 233, 1350-1354). a comparison wi ...	1993	8357616
excitonic interactions in the light-harvesting antenna of photosynthetic purple bacteria and their influence on picosecond absorbance difference spectra.	a new model of the light-harvesting antenna (core complex) of purple photosynthetic bacteria is proposed based on excitonic interactions in circular aggregates of bacteriochlorophyll molecules. the calculated absorbance difference spectra of circular aggregates demonstrate all special features observed in the experimental spectra of purple bacteria. in particular, the absorption changes with high amplitude of bleaching at the long-wavelength side of the absorption band at different excitation en ...	1993	8370458
kinetics of photooxidation of soluble cytochromes, hipip, and azurin by the photosynthetic reaction center of the purple phototrophic bacterium rhodopseudomonas viridis.	the photosynthetic reaction center of rhodopseudomonas viridis contains a bound tetraheme cytochrome c subunit which is the primary electron donor to the photooxidized special pair bacteriochlorophyll. we have tested a variety of soluble electron-transfer proteins for their ability to serve as secondary electron donors to the bacteriochlorophyll via the bound cytochrome by measuring the kinetics of reaction center heme reduction following photooxidation by a laser flash, as a function of soluble ...	1993	8387812
nucleotide sequence of the heme subunit of flavocytochrome c from the purple phototrophic bacterium, chromatium vinosum. a 2.6-kilobase pair dna fragment contains two multiheme cytochromes, a flavoprotein, and a homolog of human ankyrin.	the gene for the cytochrome subunit of chromatium vinosum flavocytochrome c (sulfide dehydrogenase) was cloned from an ecori digest of chromosomal dna. the mature cytochrome subunit contains 175 amino acid residues and two heme binding sites in agreement with the previously reported amino acid sequence. there is also a signal peptide of 25 residues, which apparently directs the protein to the periplasmic space. there are two open reading frames upstream of the heme subunit gene, which encode a t ...	1993	8390993
primary structure of chromatium tepidum high-potential iron-sulfur protein in relation to thermal denaturation.	a high-potential ferredoxin (hipip) has been purified from the thermophilic purple sulfur bacterium chromatium tepidum. most of the properties of this protein, including absorption and electron paramagnetic resonance spectra as well as redox potential, are identical to those of the similar protein isolated from the mesophilic organism chromatium vinosum. the similarity extends to the amino acid sequences, which share 74 of the 83 residues composing the primary structure of c. tepidum hipip. the ...	1993	8393645
the reaction center associated tetraheme cytochrome subunit from chromatium vinosum revisited: a reexamination of its epr properties.	the heme components of chromatophore membranes from the purple bacterium chromatium vinosum have been studied by epr. five different heme species could be distinguished on the basis of their g values, redox midpoint potentials, and orientations of heme planes with respect to the membrane plane: gz = 2.94, em = +10 mv, 40 degrees-50 degrees; gz = 2.94, em = +10 mv, 0 degree; gz = 3.1, em = +330 mv, 90 degrees; gz = 3.3, em = 360 mv, 30 degrees; gz = 3.4, em = 0 mv, no detectable orientation. four ...	1993	8395884
the electronic structure of [fe4s4]3+ clusters in proteins. an investigation of the oxidized high-potential iron-sulfur protein ii from ectothiorhodospira vacuolata.	within the framework of an investigation of the electronic structure of oxidized high-potential iron-sulfur proteins (hipip), we have studied the hipip ii from ectothiorhodospira vacuolata, which was known to have a peculiar temperature dependence of the 1h nmr isotropic hyperfine shifts. the signals of the cysteine ligand protons have been sequence specifically assigned through noe, noesy, and tocsy experiments. nine hyperfine-shifted signals are observed: seven in the downfield and two in the ...	1993	8396428
crystallization of two integral membrane pigment-protein complexes from the purple-sulfur bacterium chromatium purpuratum.		1993	8401219
specific binding of thiobacillus ferrooxidans rbcr to the intergenic sequence between the rbc operon and the rbcr gene.	the presence of two sets (rbcl1-rbcs1 and rbcl2-rbcs2) of rbc operons has been demonstrated in thiobacillus ferrooxidans fe1 (t. kusano, t. takeshima, c. inoue, and k. sugawara, j. bacteriol. 173:7313-7323, 1991). a possible regulatory gene, rbcr, 930 bp long and possibly translated into a 309-amino-acid protein, was found upstream from the rbcl1 gene as a single copy. the gene is located divergently to rbcl1 with a 144-bp intergenic sequence. as in the cases of the chromatium vinosum rbcr and a ...	1993	8432695
1h-nmr investigation of oxidized and reduced high-potential iron-sulfur protein from rhodopseudomonas globiformis.	1h one-dimensional and two-dimensional nmr spectra have been recorded for the oxidized and reduced forms of the high-potential iron-sulfur protein (hipip) from rhodopseudomonas globiformis which has the highest known reduction potential. the spectrum of the oxidized protein is similar to that of chromatium vinosum and rhodocyclus gelatinosus hipip but different from that of the hipip ii from ectothiorhodospira halophila. surprisingly, site-specific assignment has shown that in the oxidized prote ...	1993	8444166
cloning, characterization, and functional expression in escherichia coli of chaperonin (groesl) genes from the phototrophic sulfur bacterium chromatium vinosum.	a recombinant lambda phage which was able to propagate in groe mutants of escherichia coli was isolated from a chromatium vinosum genomic dna library. a 4-kbp sali dna fragment, isolated from this phage and subcloned in plasmid vectors, carried the c. vinosum genes that allowed lambda growth in these mutants. sequencing of this fragment indicated the presence of two open reading frames encoding polypeptides of 97 and 544 amino acids, respectively, which showed high similarity to the molecular ch ...	1993	8444812
molecular modeling studies on the proposed nacl-induced dimerization of chromatium vinosum high-potential iron protein.	previous work (dunham, w.r., hagen, w.r., fee, j.a., sands, r.h., dunbar, j.b., humblet, c. (1991) an investigation of chromatium vinosum high-potential iron-sulfur protein by epr and mössbauer spectroscopy; evidence for a freezing-induced dimerization in nacl solutions, biochimica biophysica acta 1079, 253-262) suggested that under specific solution conditions and slow freezing times, samples of oxidized chromatium vinosum (cv) high-potential, iron-sulfur protein (hipip) form dimeric structures ...	1993	8457586
chemical crosslinking studies of the isolated light-harvesting b800-850 complex of chromatium minutissimum.	the spatial relationship of polypeptides comprising the light-harvesting b800-850 complex of chromatium minutissimum has been studied by means of chemical crosslinking of the isolated complex with cleavable, 1.2 nm-long dithiobis(succinimidyl propionate). the samples were analyzed by different types of electrophoresis and spectrophotometrically. no difference was shown between crosslinking of the b800-850 complex either solubilized or incorporated into proteoliposomes. it was found that two main ...	1993	8462670
cloning and molecular analysis of the poly(3-hydroxybutyric acid) biosynthetic genes of thiocystis violacea.	from a genomic library of thiocystis violaceae strain 2311 in lambda l47, two adjacent ecori restriction fragments of 5361 base pairs (bp) and of 1978 bp were cloned. the 5361-bp ecori restriction fragment hybridized with a dna fragment harbouring the alcaligenes eutrophus poly(3-hydroxyalkanoate) (pha) synthase operon (phbcab) and restored the ability to synthesize and accumulate pha in pha-negative mutants derived from a. eutrophus. the nucleotide sequence analysis of both fragments revealed f ...	1993	7763384
effects of grazing by the free-living soil amoebae acanthamoeba castellanii, acanthamoeba polyphaga, and hartmannella vermiformis on various bacteria.	cultures of 10 different bacteria were used to serve as food sources for axenically grown acanthamoeba castellanii, acanthamoeba polyphaga, and hartmannella vermiformis. the nonpigmented enterobacteriaceae escherichia coli k-12 and klebsiella aerogenes appeared to be excellent feed to all three amoebae. hardly any growth or ammonium production was observed in tests with chromatium vinosum and serratia marcescens, which share the presence of pigmented compounds. distinct differences in net ammoni ...	1993	16349000
noe and two-dimensional correlated 1h-nmr spectroscopy of cytochrome c' from chromatium vinosum.	1h two-dimensional (nuclear overhauser effect spectroscopy (noesy) and two-dimensional correlated spectroscopy (cosy) spectra of cytochrome c' from chromatium vinosum have been obtained. the protein is of medium size (mr 28,000), essentially high spin (s = 5/2) although some quantum mechanical spin admixing with s = 3 2 may be present. under these circumstances noesy cross peaks have been revealed between geminal protons (alpha-ch2 propionate and beta-ch2 protons of the bound histidine) and betw ...	1992	1310939
on the redox equilibrium between h2 and hydrogenase.	redox titrations of the nickel ion in active hydrogenase from methanobacterium thermoautotrophicum and chromatium vinosum were performed in the absence of artificial redox mediators, by variation of the h2-partial pressure. these experiments revealed a redox behaviour of the nickel ion which differed remarkably from previous redox titrations in the presence of redox mediators. notably the epr signal of the species earlier characterized as monovalent nickel with bound hydrogen, behaved as an n = ...	1992	1311607
purification and characterization of chaperonin 10 from chromatium vinosum.	chromatium vinosum contains a polypeptide that is functionally and structurally similar to the escherichia coli chaperonin 10. the protein has been purified to homogeneity by sucrose density gradient centrifugation followed by gel filtration using a bio-gel a-1.5 m column. the molecular mass of chaperonin 10, as determined by gel filtration or nondenaturing polyacrylamide gel electrophoresis, is 95 kda. the oligomer is composed of seven or eight subunits. comparisons of the overall amino acid co ...	1992	1349470
assembly of plant ferredoxin-nadp+ oxidoreductase in escherichia coli requires groe molecular chaperones.	we have recently reported the expression in escherichia coli of an enzymatically competent ferredoxin-nadp+ oxidoreductase from cloned pea genes encoding either the mature enzyme or its precursor protein (ceccarelli, e. a., viale, a. m., krapp, a. r., and carrillo, n. (1991) j. biol. chem. 266, 14283-14287). processing to the mature form by bacterial protease(s) and fad assembly occurred in the bacterial cytosol. expression of ferredoxin-nadp+ reductase in chaperonin-deficient (groe-) mutants of ...	1992	1353496