Publications

measuring the immeasurable.		2001	11484018
growth of the purple bacterium rhodobacter capsulatus on the aromatic compound hippurate.	the purple nonsulfur bacterium rhodobacter capsulatus strain b10 grew phototrophically on the aromatic compound hippurate (n-benzoyl-l-glycine) and related benzoyl amino acids. absorption spectra, extraction, and gc/ms analysis of culture supernatants showed that hippurate was stoichiometrically converted to benzoate and glycine, with the latter used as a carbon or nitrogen source for growth. this conclusion was supported by detection of the enzyme hippuricase in permeabilized intact cells. chem ...	2001	11491088
aeration conditions affecting growth of purple nonsulfur bacteria in an organic wastewater treatment process.	effects of aeration on purple nonsulfur bacteria (pnsb) were studied in photobioreactors. bacterial community changes were analyzed by denaturing gradient gel electrophoresis (dgge) and fluorescence in situ hybridization (fish). dgge band pattern change was small and only few prominent bands were obtained at non-aeration condition. sequencing results of the prominent dgge bands obtained at this condition revealed that they represented mainly the pnsb, rhodobacter sphaeroides and rhodopseudomonas ...	2001	11518335
structure, expression and products of the ribosomal rna operons of rhodopseudomonas palustris no. 7.	rhodopseudomonas palustris strains carry one or two ribosomal rrna operons, and those with duplicated rrn operons grow faster. the two rrn operons in r. palustris no. 7 are virtually identical over a 54,70-bp stretch containing the genes for 16s rrna, trnaile, trnaala, 23s rrna and 5s rrna, as well as the intergenic spacers and part of the extragenic spacer. in r. palustris, unlike most bacteria with multiple rrn operons, the putative promoter sequences of the two operons are highly diverged, su ...	2001	11523795
identification and characterization of rhodopseudomonas spp., a purple, non-sulfur bacterium from microbial mats.	a species of facultative photo-organotrophic, purple, non-sulfur bacterium was isolated from mixed-species microbial mats, characterized and examined for metal tolerance and bioremediation potential. contributing mats were natural consortia of microbes, dominated by cyanobacteria and containing several species of bacteria arranged in a laminar structure, stabilized within a gel matrix. constructed microbial mats were used for bioremediation of heavy metals and organic chemical pollutants. purple ...	2001	11535416
efficient energy transfer from the carotenoid s(2) state in a photosynthetic light-harvesting complex.	previously, the spatial arrangement of the carotenoid and bacteriochlorophyll molecules in the peripheral light-harvesting (lh2) complex from rhodopseudomonas acidophila strain 10050 has been determined at high resolution. here, we have time resolved the energy transfer steps that occur between the carotenoid's initial excited state and the lowest energy group of bacteriochlorophyll molecules in lh2. these kinetic data, together with the existing structural information, lay the foundation for un ...	2001	11159459
acetate as a carbon source for hydrogen production by photosynthetic bacteria.	hydrogen is a clean energy alternative to fossil fuels. photosynthetic bacteria produce hydrogen from organic compounds by an anaerobic light-dependent electron transfer process. in the present study hydrogen production by three photosynthetic bacterial strains (rhodopseudomonas sp., rhodopseudomonas palustris and a non-identified strain), from four different short-chain organic acids (lactate, malate, acetate and butyrate) was investigated. the effect of light intensity on hydrogen production w ...	2001	11164959
simultaneous determination of delta-aminolevulinic acid, porphobilinogen, levulinic acid and glycine in culture broth by capillary electrophoresis.	capillary electrophoretic simultaneous determination of a mixture containing delta-aminolevulinic acid, porphobilinogen, levulinic acid and glycine was investigated. with increases in the sodium tetraborate buffer concentration (5-70 mm), resolution of the four components was improved, but the migration time was increased. alternatively, with increases in the applied voltage (5-22.5 kv), a shortened migration time was seen but this adversely affected resolution. the components were separated wit ...	2001	11771832
hydrophobicity and prediction of the secondary structure of membrane proteins and peptides.	reliability of the hydropathy method to predict the formation of membrane-spanning alpha-helices by integral membrane proteins and peptides whose structure is known from x-ray crystallography is analysed. it is shown that kyte-doolittle hydropathy plots do not predict accurately 22 transmembrane alpha-helices in the reaction centres (rc) of the photosynthetic bacteria rhodopseudomonas viridis and rhodobacter sphaeroides (r-26). the accuracy of prediction for these proteins was improved using an ...	2001	11699870
microbial genomes. sequences reveal borrowed genes.		2001	11721026
dynamics of excitation energy transfer in the lh1 and lh2 light-harvesting complexes of photosynthetic bacteria.	photosynthetic light harvesting is a unique life process that occurs with amazing efficiency. since the discovery of the structure of the bacterial peripheral light-harvesting complex (lh2), this process has been studied using a variety of advanced laser spectroscopic methods. we are now in a position to discuss the physical origins of excitation energy transfer and trapping in the lh2 and lh1 antennae of photosynthetic purple bacteria. we demonstrate that the time evolution of the state created ...	2001	11735388
cleavage of the iron-methionine bond in c-type cytochromes: crystal structure of oxidized and reduced cytochrome c(2) from rhodopseudomonas palustris and its ammonia complex.	the three-dimensional structures of the native cytochrome c(2) from rhodopseudomonas palustris and of its ammonia complex have been obtained at ph 4.4 and ph 8.5, respectively. the structure of the native form has been refined in the oxidized state at 1.70 a and in the reduced state at 1.95 a resolution. these are the first high-resolution crystal structures in both oxidation states of a cytochrome c(2) with relatively high redox potential (+350 mv). the differences between the two oxidation sta ...	2002	11742117
the 7.5-a electron density and spectroscopic properties of a novel low-light b800 lh2 from rhodopseudomonas palustris.	a novel low-light (ll) adapted light-harvesting complex ii has been isolated from rhodopseudomonas palustris. previous work has identified a ll b800-850 complex with a heterogeneous peptide composition and reduced absorption at 850 nm. the work presented here shows the 850 nm absorption to be contamination from a high-light b800-850 complex and that the true ll light-harvesting complex ii is a novel b800 complex composed of eight alpha beta(d) peptide pairs that exhibits unique absorption and ci ...	2002	11806936
the aquatic budding bacterium blastobacter denitrificans is a nitrogen-fixing symbiont of aeschynomene indica.	blastobacter spp. are freshwater bacteria that form rosette structures by cellular attachment to a common base. comparative analyses of ribosomal 16s rrna gene and internally transcribed spacer region sequences indicated that b. denitrificans is a member of the alpha-subdivision of proteobacteria. among the alpha-proteobacteria, b. denitrificans was related to a cluster of genera, including rhodopseudomonas palustris, afipia felis, nitrobacter hamburgensis, and bradyrhizobium spp. although the p ...	2002	11872460
enzymatic synthesis and purification of aromatic coenzyme a esters.	two recombinant his-tagged proteins, a plant 4-coumarate:coenzyme a ligase (ec 6.2.1.12) and a bacterial benzoate:coenzyme a ligase (ec 6.2.1.25), were expressed in escherichia coli and purified in a single step using ni-chelating chromatography. purified enzymes were used to synthesize cinnamoyl-coenzyme a (coa), p-coumaroyl-coa, feruloyl-coa, caffeoyl-coa, and benzoyl-coa. conversions up to 95% were achieved. using a rapid solid-phase extraction procedure, the target coa esters were isolated w ...	2002	11878812
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 ...	2002	11916874
relationship between hydrogen-bonding network and reduction potential in c-type cytochromes.		2002	11959147
taxis response of various denitrifying bacteria to nitrate and nitrite.	the taxis response of rhodobacter sphaeroides 2.4.1 and 2.4.3, rhodopseudomonas palustris, and agrobacterium tumefaciens to nitrate and nitrite was evaluated by observing the macroscopic behavior of cells suspended in soft agar and incubated under various conditions. r. sphaeroides 2.4.3, which is capable of both nitrate and nitrite reduction, showed a taxis response to both nitrate and nitrite. r. sphaeroides 2.4.1, which contains nitrate reductase but not nitrite reductase, did not show a taxi ...	2002	11976082
photosynthetic apparatus of purple bacteria.		2002	11997980
bacteriophytochrome controls photosystem synthesis in anoxygenic bacteria.	plants use a set of light sensors to control their growth and development in response to changes in ambient light. in particular, phytochromes exert their regulatory activity by switching between a biologically inactive red-light-absorbing form (pr) and an active far-red-light absorbing form (pfr). recently, biochemical and genetic studies have demonstrated the occurrence of phytochrome-like proteins in photosynthetic and non-photosynthetic bacteria--but little is known about their functions. he ...	2002	12000965
effect of protein relaxation on electron transfer from the cytochrome subunit to the bacteriochlorophyll dimer in rps. sulfoviridis reaction centers within mixed adiabatic/nonadiabatic model.	the broad set of nonexponential electron transfer (et) kinetics in reaction centers (rc) from rhodopseudomonas sulfoviridis in temperature range 297-40 k are described within a mixed adiabatic/nonadiabatic model. the key point of the model is the combination of sumi-marcus and rips-jortner approaches which can be represented by the separate contributions of temperature-independent vibrational (v) and temperature-dependent diffusive (d) coordinates to the preexponential factor, to the free energy ...	2002	12009432
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 ...	2002	12018287
phototrophic transformation of phenol to 4-hydroxyphenylacetate by rhodopseudomonas palustris.	newly isolated and culture collection strains of rhodopseudomonas palustris were able to transform phenol to 4-hydroxyphenylacetate under phototrophic conditions in the presence of acetate, malate, benzoate, or cinnamate as growth substrates. the reaction was examined with uniformly (14)c-labelled phenol and the product was identified by hplc retention time, uv-scans, and (1)h- and (13)c-nmr analysis. the transformation reaction was detectable in cell-free extracts in the presence of nad(+) and ...	2002	12021805
kinetics, energetics, and electronic coupling of the primary electron transfer reactions in mutated reaction centers of blastochloris viridis.	femtosecond spectroscopy in combination with site-directed mutagenesis has been used to study the dynamics of primary electron transfer in native and 12 mutated reaction centers of blastochloris (b) (formerly called rhodopseudomonas) viridis. the decay times of the first excited state p* vary at room temperature between of 0.6 and 50 ps, and at low temperatures between 0.25 and 90 ps. these changes in time constants are discussed within the scope of nonadiabatic electron transfer theory using di ...	2002	12023243
quantum control of energy flow in light harvesting.	coherent light sources have been widely used in control schemes that exploit quantum interference effects to direct the outcome of photochemical processes. the adaptive shaping of laser pulses is a particularly powerful tool in this context: experimental output as feedback in an iterative learning loop refines the applied laser field to render it best suited to constraints set by the experimenter. this approach has been experimentally implemented to control a variety of processes, but the extent ...	2002	12037563
evolutionary relationship of phototrophic bacteria in the alpha-proteobacteria based on farnesyl diphosphate synthase.	partial sequences of farnesyl diphosphate (fpp) synthase genes derived from the rhodobacter-rhodovulum group and from the rhodopseudomonas palustris-bradyrhizobium japonicum group of the alpha-proteobacteria were subjected to phylogenetic analysis to investigate the relationships of phototrophic and non-phototrophic bacteria in the alpha-proteobacteria . the four rhodovulum species formed a monophyletic group within the rhodobacter cluster, and agrobacterium ferrugineum iam 12616(t) intermingled ...	2002	12055311
genotypic and phenotypic diversity within species of purple nonsulfur bacteria isolated from aquatic sediments.	to assess the extent of genotypic and phenotypic diversity within species of purple nonsulfur bacteria found in aquatic sediments, a total of 128 strains were directly isolated from agar plates that had been inoculated with sediment samples from haren and de biesbosch in the netherlands. all isolates were initially characterized by box-pcr genomic dna fingerprinting, and 60 distinct genotypes were identified. analyses of 16s rrna gene sequences of representatives of each genotype showed that fiv ...	2002	12089030
heterologous expression of a bacterial homospermidine synthase gene in transgenic tobacco: effects on the polyamine pathway.	homospermidine synthase (hss) is a branch-point enzyme that links the secondary pathway (pyrrolizidine alkaloids) to primary metabolism (polyamines). since the diamine putrescine is a precursor of homospermidine and nicotine in tobacco, we performed heterologous expression of a bacterial homospermidine synthase gene (hss)in nicotiana tabacum and determined the effect on free and conjugated polyamine levels. the hss gene from rhodopseudomonas viridis was placed under the control of the cauliflowe ...	2002	12112034
cysteine activation is an inherent in vitro property of prolyl-trna synthetases.	aminoacyl-trna synthetases are well known for their remarkable precision in substrate selection during aminoacyl-trna formation. some synthetases enhance the accuracy of this process by editing mechanisms that lead to hydrolysis of incorrectly activated and/or charged amino acids. prolyl-trna synthetases (prorss) can be divided into two structurally divergent groups, archaeal-type and bacterial-type enzymes. a striking difference between these groups is the presence of an insertion domain (appro ...	2002	12130657
conservation of the free energy change of the alkaline isomerization in mitochondrial and bacterial cytochromes c.	the thermodynamic parameters of the alkaline transition for oxidized native yeast iso-1 cytochrome c and rhodopseudomonas palustris cytochrome c(2) (cytc(2)) have been determined through direct electrochemistry experiments carried out at variable ph and temperature and compared to those for horse and beef heart cytochromes c. we have found that both transition enthalpy and entropy are remarkably species dependent, following the order r. palustris cytc(2) >> beef (horse) heart cytc>yeast iso-1 cy ...	2002	12147260
aerobic metabolism of phenylacetic acids in azoarcus evansii.	the aerobic metabolism of phenylacetic acid (pa) and 4-hydroxyphenylacetic acid (4-ohpa) was investigated in the beta-proteobacterium azoarcus evansii. evidence for the existence of two independent catabolic pathways for pa and 4-ohpa is presented. 4-ohpa metabolism involves the formation of 2,5-dihydroxyphenylacetate (homogentisate) and maleylacetoacetate catalyzed by specifically induced 4-ohpa 1-monooxygenase and homogentisate 1,2-dioxygenase. the metabolism of pa starts by its activation to ...	2002	12189419
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 ...	2002	12202393
in search of a bacterial species definition. 1997.		2002	12362904
[hydrogen photoproduction from acetate by rhodopseudomonas palustris].	based on the characteristics of metabolism of photosynthetic bacteria and the major kinds of organic compounds produced in wastewater degradation, eleven kinds of organic compounds were chosen for hydrogen photoproduction using rhodopseudomonas palustris z strain. the maximal volumetric h2 productivity was obtained using acetate as the sole carbon source and electron donor. the kinetics of cell growth and h2 liberation, and the influences of several major limiting factors on photoevolution of h2 ...	2002	12385249
vibrational spectroscopy favors a unique qb binding site at the proximal position in wild-type reaction centers and in the pro-l209 --> tyr mutant from rhodobacter sphaeroides.	in the various x-ray structures of native reaction centers (rcs) from the photosynthetic bacterium rhodobacter sphaeroides, two distinct main binding sites (distal and proximal) for the secondary quinone q(b) have been described in the literature. the movement of q(b) from its distal to proximal position has been proposed to account for the conformational gate limiting the rate of the first electron transfer from the primary quinone q(a-) to q(b). recently, q(b) was found to bind in the proximal ...	2002	12390017
evolutionary implications of phylogenetic analyses of the gene transfer agent (gta) of rhodobacter capsulatus.	the gene transfer agent (gta) of the a-proteobacterium rhodobacter capsulatus is a cell-controlled genetic exchange vector. genes that encode the gta structure are clustered in a 15-kb region of the r. capsulatus chromosome, and some of these genes show sequence similarity to known bacteriophage head and tail genes. however, the production of gta is controlled at the level of transcription by a cellular two-component signal transduction system. this paper describes homologues of both the gta str ...	2002	12399927
characterization of the rrna locus of pfiesteria piscicida and development of standard and quantitative pcr-based detection assays targeted to the nontranscribed spacer.	pfiesteria piscicida is a heterotrophic dinoflagellate widely distributed along the middle atlantic shore of the united states and associated with fish kills in the neuse river (north carolina) and the chesapeake bay (maryland and virginia). we constructed a genomic dna library from clonally cultured p. piscicida and characterized the nontranscribed spacer (nts), small subunit, internal transcribed spacer 1 (its1), 5.8s region, its2, and large subunit of the rrna gene cluster. based on the p. pi ...	2002	12406730
protein-lipid interactions in the purple bacterial reaction centre.	the purple bacterial reaction centre uses the energy of sunlight to power energy-requiring reactions such as the synthesis of atp. during the last 20 years, a combination of x-ray crystallography, spectroscopy and mutagenesis has provided a detailed insight into the mechanism of light energy transduction in the bacterial reaction centre. in recent years, structural techniques including x-ray crystallography and neutron scattering have also been used to examine the environment of the reaction cen ...	2002	12409196
rhodopseudomonas acidophila strain 10050 contains photosynthetic lh2 antenna complexes that are not enriched with phosphatidylglycerol, and the phospholipids have a fatty acyl composition that is unusual for purple non-sulfur bacteria.	the phospholipid composition of rhodopseudomonas acidophila strain 10050 grown aerobically or anaerobically in the light was determined. the major phospholipids present in the aerobic cells were phosphatidylethanolamine (pe; 54%), phosphatidylglycerol (pg; 24%) and cardiolipin (diphosphatidylglycerol, dpg) (14%), together with phosphatidylcholine (pc; 5%). on moving the cells to anaerobic photosynthetic growth in the light pe remained the major phospholipid (37-49%), but there was a major change ...	2002	12460683
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 ...	2002	12484747
on the involvement of the water-polaron mechanism in energy trapping by reaction centers of purple bacteria.	a locus for binding a mobile water molecule was searched for in the immediate vicinity of the special pair in the reaction center. using the proteus pc-program (a part of the grasp package) atomic structures of the reaction centers were analyzed in purple bacteria rhodopseudomonas viridis and rhodobacter sphaeroides. in both structures the loci for binding mobile water molecules were found at the distance of about 4.5 a from the middle of the special pair in the reaction center. the reorientatio ...	2002	12495417
photobiodegradation of pyridine by rhodopseudomonas palustris ja1.	a purple non-sulfur bacterium isolated from dairy effluent was identified as rps. palustris ja1. this organism was able to grow on pyridine as sole source of carbon in a light dependent anaerobic process with a doubling time of 30 h. intermediates of pyridine photobiodegradation were identified as glycine and malonate, produced in stoichiometric molar ratios with simultaneous utilization, yielding biomass.	2002	12597034
a fast in silico simulation of ion flux through the large-pore channel proteins.	the psst program (see accompanying article) utilizes the detailed structure of a large-pore channel protein as the sole input for selection of trajectories along which negative and positive ions propagate. in the present study we applied this program to reconstruct the ion flux through five large-pore channel proteins (phoe, ompf, the wt r. blastica general diffusion porin and two of its mutants). the conducting trajectories, one for positive and one for negative particles, are contorted pathway ...	2002	12496073
rhodopseudomonas faecalis sp. nov., a phototrophic bacterium isolated from an anaerobic reactor that digests chicken faeces.	five isolates of a previously undescribed species of purple non-sulfur phototrophic bacteria were characterized. they were gram-negative, had mobile, budding vibrioid cells and contained lamellar intracytoplasmic membranes. cultures produced red pigments in the light. live cells of photosynthetic cultures exhibited absorption maxima at 382, 460-464, 494-496, 534-538, 596, 804-806 and 870-874 nm, indicating the presence of bacteriochlorophyll a and carotenoids belonging to the spirilloxanthin ser ...	2002	12508868
[a comparative study of the isocitrate dehydrogenases of chlorobium limicola forma chlorobium thiosulfatophilum and rhodopseudomonas palustris].	the carboxylation of 2-oxoglutarate in the reductive tricarboxylic acid cycle in the obligate photolithotroph chlorobium limicola forma thiosulfatophilum and the oxidation of isocitrate in the tricarboxylic acid cycle in the photoheterotroph rhodopseudomonas palustris are catalyzed by isocitrate dehydrogenases. a comparative study of these enzymes isolated from the two bacteria showed that they virtually do not differ in the enzymatic and kinetic properties.	2002	12526196
detergent structure in crystals of the integral membrane light-harvesting complex lh2 from rhodopseudomonas acidophila strain 10050.	integral membrane proteins are solubilized by their incorporation into a detergent micelle. the detergent micelle has a critical influence on the formation of a three-dimensional crystal lattice. the bulk detergent phase is not seen in x-ray crystal structures of integral membrane proteins, due to its disordered character. here, we describe the detergent structure present in crystals of the peripheral light-harvesting complex of the purple bacteria rhodopseudomonas acidophila strain 10050 at a m ...	2003	12547211
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 ...	2003	12570988
nanodissection and high-resolution imaging of the rhodopseudomonas viridis photosynthetic core complex in native membranes by afm. atomic force microscopy.	in photosynthesis, highly organized multiprotein assemblies convert sunlight into biochemical energy with high efficiency. a challenge in structural biology is to analyze such supramolecular complexes in native membranes. atomic force microscopy (afm) with high lateral resolution, high signal-to-noise ratio, and the possibility to nanodissect biological samples is a unique tool to investigate multiprotein complexes at molecular resolution in situ. here we present high-resolution afm of the photo ...	2003	12574504
an artificial antenna complex containing four ru(bpy)3(2+)-type chromophores as light-harvesting components and a ru(bpy)(cn)4(2-) subunit as the energy trap. a structural motif which resembles the natural photosynthetic systems.	a cyclam subunit bearing four light-harvesting ru(bpy)3(2+)-type species is connected to a ru(ii) compound having low-lying excited states (energy trap) by hydrogen bonding: the light absorbed by the light-harvesting elements is funnelled to the energy trap with high efficiency.	2003	12585433
the structure and thermal motion of the b800-850 lh2 complex from rps.acidophila at 2.0a resolution and 100k: new structural features and functionally relevant motions.	the structure at 100k of integral membrane light-harvesting complex ii (lh2) from rhodopseudomonas acidophila strain 10050 has been refined to 2.0a resolution. the electron density has been significantly improved, compared to the 2.5a resolution map, by high resolution data, cryo-cooling and translation, libration, screw (tls) refinement. the electron density reveals a second carotenoid molecule, the last five c-terminal residues of the alpha-chain and a carboxy modified alpha-met1 which forms t ...	2003	12595263
removal of organics and nutrients from tannery effluent by advanced integrated wastewater pond systems technology.	in this study, a pilot-scale experiment was carried out on a pre-settled combined tannery effluent from modjo tannery, ethiopia, to evaluate the feasibility of the advanced integrated wastewater pond systems or aiwps technology, for the treatment of tannery effluent. the pilot-scale aiwps facility was comprised of an advanced facultative pond (afp), secondary facultative pond (sfp) and maturation pond (mp) all arranged in series. three feed phases with low, moderate and overloading organic loadi ...	2003	14510225
helical lévy walks: adjusting searching statistics to resource availability in microzooplankton.	the searching trajectories of different animals can be described with a broad class of flight length (lj) distributions with p(lj) = lj-mu. theoretical studies have shown that changes in these distributions (i.e., different mu values) are key to optimizing the long-term encounter statistics under certain searcher-resource scenarios. in particular, they predict the advantage of lévy searching (mu approximately 2) over brownian motion (mu > or = 3) for low-prey-density scenarios. here, we present ...	2003	14566048
membrane protein stability: high pressure effects on the structure and chromophore-binding properties of the light-harvesting complex lh2.	using the bacteriochlorophyll a (bchl) cofactors as intrinsic probes to monitor changes in membrane protein structure, we investigate the response to high-pressure of the lh2 complexes from the photosynthetic bacteria rhodobacter sphaeroides 2.4.1 and rhodopseudomonas acidophila 10050. by ft-raman spectroscopy, we demonstrate that high pressure does not induce significant distortion of the protein-bound 850 nm-absorbing bacteriochlorophyll molecules, or break of the hydrogen bond they are involv ...	2003	14596617
acidobacteria form a coherent but highly diverse group within the bacterial domain: evidence from environmental genomics.	acidobacteria have been established as a novel phylum of bacteria that is consistently detected in many different habitats around the globe by 16s rdna-based molecular surveys. the phylogenetic diversity, ubiquity and abundance of this group, particularly in soil habitats, suggest an important ecological role and extensive metabolic versatility. however, the genetic and physiological information about acidobacteria is scarce. in order to gain insight into genome structure, evolution and diversit ...	2003	14617179
the structural basis of light-harvesting in purple bacteria.	a typical purple bacterial photosynthetic unit consists of two types of light-harvesting complex (lh1 and lh2) together with a reaction centre. this short review presents a description of the structure of the lh2 complex from rhodopseudomonas acidophila, which has recently been improved to a resolution of 2.0 a [papiz et al., j. mol. biol. 326 (2003) 1523-1538]. we show how this structure has helped to reveal the details of the various excitation energy transfer events in which it is involved.	2003	14630315
crystal structure of the rc-lh1 core complex from rhodopseudomonas palustris.	the crystal structure at 4.8 angstrom resolution of the reaction center-light harvesting 1 (rc-lh1) core complex from rhodopseudomonas palustris shows the reaction center surrounded by an oval lh1 complex that consists of 15 pairs of transmembrane helical alpha- and beta-apoproteins and their coordinated bacteriochlorophylls. complete closure of the rc by the lh1 is prevented by a single transmembrane helix, out of register with the array of inner lh1 alpha-apoproteins. this break, located next ...	2003	14671305
shotgun proteomic analysis of a chromatophore-enriched preparation from the purple phototrophic bacterium rhodopseudomonas palustris.	a proteomics approach was evaluated for analysis of photosyntheis-related proteins that are characteristic of chromatophores, particles derived from purple phototrophic bacterial intracytoplasmic membranes. proteins of purified chromatophores from rhodopseudomonas palustris were solubilized and digested with trypsin, to create a collection of peptides that were fractionated by liquid chromatography. peptide sequences were determined and assigned to specific proteins by analysis of tandem mass sp ...	2003	16245051
characterization of expressed pigmented core light harvesting complex (lh 1) in a reaction center deficient mutant of blastochloris viridis.	the utility of photosynthetically defective mutants in the purple photosynthetic bacterium blastochloris viridis (formerly rhodopseudomonas viridis)was demonstrated with construction of a reaction-center deficient mutant, lh 1-h. this lh 1-h mutant has a photosynthetic apparatus in which most of the puf operon genes were deleted, resulting in an organism containing only the genes for the light harvesting polypeptides and the h subunit of the reaction center. this b. viridisstrain containing a tr ...	2003	16228384
anaerobic biodegradation of aromatic compounds.	many aromatic compounds and their monomers are existing in nature. besides they are introduced into the environment by human activity. the conversion of these aromatic compounds is mainly an aerobic process because of the involvement of molecular oxygen in ring fission and as an electron acceptor. recent literatures indicated that ring fission of monomers and obligomers mainly occurs in anaerobic environments through anaerobic respiration with nitrate, sulphate, carbon dioxide or carbonate as el ...	2003	15242297
the ring structure and organization of light harvesting 2 complexes in a reconstituted lipid bilayer, resolved by atomic force microscopy.	the main function of the transmembrane light-harvesting complexes in photosynthetic organisms is the absorption of a light quantum and its subsequent rapid transfer to a reaction center where a charge separation occurs. a combination of freeze-thaw and dialysis methods were used to reconstitute the detergent-solubilized light harvesting 2 complex (lh2) of the purple bacterium rhodopseudomonas acidophila strain 10050 into preformed egg phosphatidylcholine liposomes, without the need for extra che ...	2003	12668456
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 ...	2003	12669192
[calculation of spectra of absorption and circular dichroism of rhodopseudomonas acidophila light harvesting complexes based on roentgen structural data].	absorption and circular dichroism spectra of two forms of the peripheral light-harvesting complex from photosynthetic purple bacteria rhodopseudomonas acidophila were calculated. calculations were carried out on the basis of exciton theory for circular aggregates of bacteriochlorophyll molecules and x-ray data for these forms of the complex. it was shown that theoretical spectra fit well experimental ones at the same values of excitation energy, homogeneous and inhomogeneous broadening, and band ...	2003	12723345
some properties of glycine aminotransferase purified from rhodopseudomonas palustris no. 7 concerning extracellular porphyrin production.	glycine aminotransferase (ec 2.6.1.4; glyat) was presumed to be an enzyme concerning the supply of glycine for the extracellular porphyrin production by rhodopseudomonas palustris no. 7. glyat was purified from strain no. 7 as an electrophoretically homogenous protein. the enzyme was a monomer protein with the molecular weight of about 42,000. from the absorption spectrum of the enzyme (350 nm, 410 nm), it was indicated that the enzyme had pyridoxal phosphate as a prosthetic group. the enzyme sh ...	2003	12784618
influence of carotenoid molecules on the structure of the bacteriochlorophyll binding site in peripheral light-harvesting proteins from rhodobacter sphaeroides.	in the lh2 proteins from rhodobacter (rb.) sphaeroides, the hydrogen bonds between the bacteriochlorophyll (bchl) molecules and their proteic binding sites exhibit a strong variance with respect to carotenoid content and type. in the absence of the carotenoid molecule, such as in the lh2 from rb. sphaeroides r26.1, the void in the protein structure induces a significant reorganization of the binding site of both bchl molecules responsible for the 850 nm absorption, which is not observed when the ...	2003	12795622
afm imaging of bacteria in liquid media immobilized on gelatin coated mica surfaces.	immobilization of particulates, especially biomolecules and cells, onto surfaces is critical for imaging with the atomic force microscope (afm). in this paper, gelatin coated mica surfaces are shown to be suitable for immobilizing and imaging both gram positive, staphylococcus aureus, and gram negative, escherichia coli, bacteria in both air and liquid environments. gelatin coated surfaces are shown to be superior to poly-l-lysine coated surfaces that are commonly used for the immobilization of ...	2003	12801673
multichannel carotenoid deactivation in photosynthetic light harvesting as identified by an evolutionary target analysis.	a new channel of excitation energy deactivation in bacterial light harvesting was recently discovered, which leads to carotenoid triplet population on an ultrafast timescale. here we show that this mechanism is also active in lh2 of rhodopseudomonas acidophila through analysis of transient absorption data with an evolutionary target analysis. the algorithm offers flexible testing of kinetic network models with low a priori knowledge requirements. it applies universally to the simultaneous fittin ...	2003	12829499
in most bradyrhizobium groups sequence comparison of 16s-23s rdna internal transcribed spacer regions corroborates dna-dna hybridizations.	in an extension of a previous small-scale test to assess the use of 16s-23s rdna internal transcribed spacer (its) sequences for rapid grouping of bradyrhizobia, we have sequenced the its region of 32 isolates of bradyrhizobium that had previously been studied using aflp and dna-dna hybridizations. we also included representatives of afipia and rhodopseudomonas. our results indicate that its sequences are very diverse among bradyrhizobia. nevertheless, for most of the bradyrhizobia, the grouping ...	2003	12866847
phytoplankton successions under ice cover in four lakes located in north-eastern sweden: effects of liming.	phytoplankton successions under ice cover (january-march) were determined in four oligotrophic lakes (burtjärn, aspen, vialamptjärn and storkorstjärn) located in north-eastern sweden. the total phosphorus concentration in the lakes was less than 10 micrograms/l. lake burtjärn (reference lake) had a similar hydrology as lake aspen. storkorstjärn and vialamptjärn were of similar hydrology and had heavily colored water (> 100 mgpt/l). aspen as well as vialamptjärn became continuously limed with cal ...	2003	12879750
augmentation of h2 photoproduction in rhodopseudomonas palustris by n-heterocyclic aromatic compounds.	increases of 23- (5.6 mmol acetylene reduced mg dry wt(-1)) and 16- (4 mmol acetylene reduced mg dry wt(-1)) fold in nitrogenase activity and 12- (671 microl h2 mg dry wt(-1) h(-1)) and 6- (349 microl mg dry wt(-1) h(-1)) fold in h2 photoproduction in rhodopseudomonas palustris ja1 over 24 h were achieved with pyrazine 2-carboxylate (3 mm) and 3-picoline (3 mm), respectively, and were higher than earlier reports of enhancement (1.5 to 5-fold) in biological h2 production using various alternative ...	2003	12882311
effects of photosynthetic reaction center h protein domain mutations on photosynthetic properties and reaction center assembly in rhodobacter sphaeroides.	purple bacterial photosynthetic reaction center (rc) h proteins comprise three cellular domains: an 11 amino acid n-terminal sequence on the periplasmic side of the inner membrane; a single transmembrane alpha-helix; and a large c-terminal, globular cytoplasmic domain. we studied the roles of these domains in rhodobacter sphaeroides rc function and assembly, using a mutagenesis approach that included domain swapping with blastochloris viridis rc h segments and a periplasmic domain deletion. all ...	2003	12885224
construction of a genetically engineered microorganism for co2 fixation using a rhodopseudomonas/escherichia coli shuttle vector.	the co2 fixation ability of rhodopseudomonas palustris dh was enhanced by introducing the recombinant plasmid pmg-cbbm containing the form ii ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco) gene (cbbm) isolated from rps. palustris no. 7. sequencing of a 3.0-kb psti fragment containing the cbbm gene revealed an open reading frame encoding 461 amino acids, homologous to known cbbm genes, with a ribosome binding site upstream of cbbm and a terminator downstream of cbbm, without promoter. ...	2003	12900023
changing concepts in the systematics of bacterial nitrogen-fixing legume symbionts.	as of february 2003, bacteria that form nitrogen-fixing symbiotic associations with legumes have been confirmed in 44 species of 12 genera. phylogenies of these taxa containing legume symbionts based on the comparative analysis of 16s rdna sequences show that they are not clustered in one lineage but are distributed in the classes alphaproteobacteria and betaproteobacteria, and dispersed over the following nine monophyletic groups, being intermingled with other taxa that do not contain legume sy ...	2003	12949698
biogeography of the purple nonsulfur bacterium rhodopseudomonas palustris.	the biogeography of the purple nonsulfur bacterium rhodopseudomonas palustris on a local scale was investigated. thirty clones of phototrophic bacteria were isolated from each of five unevenly spaced sampling locations in freshwater marsh sediments along a linear 10-m transect, and a total of 150 clones were characterized by box-pcr genomic dna fingerprinting. cluster analysis of 150 genomic fingerprints yielded 26 distinct genotypes, and 106 clones constituted four major genotypes that were rep ...	2003	12957900
spatial distribution of rhodopseudomonas palustris ecotypes on a local scale.	the number, spatial distribution, and significance of genetically distinguishable ecotypes of prokaryotes in the environment are poorly understood. oda et al. (y. oda, b. star, l. a. huisman, j. c. gottschal, and l. j. forney, appl. environ. microbiol. 69:xxx-xxx, 2003) have shown that rhodopseudomonas palustris ecotypes were lognormally distributed along a 10-m transect and that multiple strains of the species could coexist in 0.5-g sediment samples. to extend these observations, we investigate ...	2003	12957901
tuning heme redox potentials in the cytochrome c subunit of photosynthetic reaction centers.	the photosynthetic reaction center (rc) from rhodopseudomonas viridis contains four cytochrome c hemes. they establish the initial part of the electron transfer (et) chain through the rc. despite their chemical identity, their midpoint potentials cover an interval of 440 mv. the individual heme midpoint potentials determine the et kinetics and are therefore tuned by specific interactions with the protein environment. here, we use an electrostatic approach based on the solution of the linearized ...	2003	12975370
cloning, heterologous expression, and characterization of recombinant class ii cytochromes c from rhodopseudomonas palustris.	the cytochrome (cyt) c', cyt c(556), and cyt c(2) genes from rhodopseudomonas palustris have been cloned; recombinant cyt c' and cyt c(556) have been expressed, purified, and characterized. unlike mitochondrial cyt c, these two proteins are structurally similar to cyt b(562), in which the heme is embedded in a four-helix bundle. the hemes in both recombinant proteins form covalent thioether links to two cys residues. uv/vis spectra of the fe(ii) and fe(iii) states of the recombinant cyts are ide ...	2003	12495812
cloning, expression, and characterization of 5-aminolevulinic acid synthase from rhodopseudomonas palustris kugb306.	the hema gene encoding 5-aminolevulinic acid synthase (alas) was cloned from the genomic dna of photosynthetic bacterium rhodopseudomonas palustris kugb306. the deduced protein (alas) of this gene contained 409 amino acids. the hema gene was subcloned into an expression vector pgex-kg and the encoded protein was overexpressed as a fusion protein with glutathione-s-transferase (gst) in escherichia coli bl21. the recombinant alas was purified and isolated free of the fusion partner (gst) by affini ...	2004	15251194
analysis of absorption spectra of rc from the bacteria blastochlorii viridis in near ir region using high-order derivative spectroscopy.		2004	15253552
the nitrogen-fixing gene (nifh) of rhodopseudomonas palustris: a case of lateral gene transfer?	nitrogen fixation is catalysed by some photosynthetic bacteria. this paper presents a phylogenetic comparison of a nitrogen fixation gene (nifh) with the aim of elucidating the processes underlying the evolutionary history of rhodopseudomonas palustris. in the nifh phylogeny, strains of rps. palustris were placed in close association with rhodobacter spp. and other phototrophic purple non-sulfur bacteria belonging to the alpha-proteobacteria, separated from its close relatives bradyrhizobium jap ...	2004	15256566
predator/prey interaction between pfiesteria piscicida and rhodomonas mediated by a marine alpha proteobacterium.	the dinoflagellate pfiesteria piscicida coexists with bacteria in aquatic environments and as such, may interact with them at the physiological level. this study was designed to investigate the influence of bacteria, present in a clonal culture of pfiesteria piscicida, on the predator/prey relationship of this dinoflagellate with the alga rhodomonas. a series of replenishment experiments with bacteria isolated from p. piscicida clonal culture and the bacteria-free p. piscicida derived from the s ...	2004	15259269
analysis of diversity among 3-chlorobenzoate-degrading strains of rhodopseudomonas palustris.	the phenotypic and genetic characteristics of 14 strains of the purple nonsulfur bacterium rhodopseudomonas palustris were studied to assess diversity within this species. while all strains had certain phenotypic characteristics in common, including the ability to metabolize benzoate and degrade 2- and 3-chlorobenzoate, there were also significant differences among the strains such as the rate of growth in media containing benzoate as a carbon source. genetic characterization of the strains reve ...	2004	15259271
odorous swine wastewater treatment by purple non-sulfur bacteria, rhodopseudomonas palustris, isolated from eutrophicated ponds.	three strains of phototrophic, purple, non-sulfur bacteria, isolated from eutrophic ponds, were used to treat odorous swine wastewater. one isolate, rhodopseudomonas palustris, when cultured in swine wastewater without supplementation for 7 d, removed odorous organic acids (170 mg l(-1)), cod (10,000 mg l(-1)) and phosphate (180 mg l(-1)).	2004	15269554
heterologous production of the antifungal polyketide antibiotic soraphen a of sorangium cellulosum so ce26 in streptomyces lividans.	the antifungal polyketide soraphen a is produced by the myxobacterium sorangium cellulosum so ce26. the slow growth, swarming motility and general intransigence of the strain for genetic manipulations make industrial strain development, large-scale fermentation and combinatorial biosynthetic manipulation of the soraphen producer very challenging. to provide a better host for soraphen a production and molecular engineering, the biosynthetic gene cluster for this secondary metabolite was integrate ...	2004	15289572
the electron conduction of photosynthetic protein complexes embedded in a membrane.	the conductivity of two photosynthetic protein-pigment complexes, a light harvesting 2 complex and a reaction center, was measured with an atomic force microscope capable of performing electrical measurements. current-voltage measurements were performed on complexes embedded in their natural environment. embedding the complexes in lipid bilayers made it possible to discuss the different conduction behaviors of the two complexes in light of their atomic structure.	2004	14988007
iron(ii) carboxylate complexes based on a tetraimidazole ligand as models of the photosynthetic non-heme ferrous sites: synthesis, crystal structure, and mössbauer and magnetic studies.	the preparations, x-ray structures, and detailed physical characterization are presented for new complexes involving an iron(ii) center, a tetraimidazole ligand (tim), and different carboxylates. [fe(tim)(c(6)h(5)ch(2)co(2))](clo(4)) (1) crystallizes in the pbca space group with a = 10.8947(13), b = 20.343(2), and c = 22.833(3) a, z = 8, and v = 5060.6(11) a(3). [fe(tim)(ch(3)co(2))](clo(4)) (2) crystallizes in the ia space group with a = 17.117(2), b = 10.3358(12), and c = 25.658(3) a, beta = 9 ...	2004	15018534
from ruthenium(ii) to iridium(iii): 15 years of triads based on bis-terpyridine complexes.	in order to mimic the photosynthetic reaction centre and better understand photoinduced electron transfer processes, a family of compounds has been studied for the past 15 years. these are transition metal complexes, m(tpy)(2) where tpy is a 2,2':6',2" terpyridine based ligand, bearing on one side a donor group and on the other side an acceptor group. the resulting triad molecules or their two-component reference compounds (donor-m(tpy)(2) and m(tpy)(2-acceptor) can contain ru, os, rh or ir as t ...	2004	15026819
electron acquisition system constructed from an nad-independent d-lactate dehydrogenase and cytochrome c2 in rhodopseudomonas palustris no. 7.	the activities of nad-independent d- and l-lactate dehydrogenases (d-ldh, l-ldh) were detected in rhodopseudomonas palustris no. 7 grown photoanaerobically on lactate. one of these enzymes, d-ldh, was purified as an electrophoretically homogeneous protein (m(r), about 235,000; subunit m(r) about 57,000). the pi was 5.0. the optimum ph and temperature of the enzyme were ph 8.5 and 50 degrees c, respectively. the km of the enzyme for d-lactate was 0.8 mm. the enzyme had narrow substrate specificit ...	2004	15056881
champions of versatility.		2004	15058278
root nodule bradyrhizobium spp. harbor tfdaalpha and cada, homologous with genes encoding 2,4-dichlorophenoxyacetic acid-degrading proteins.	the distribution of tfdaalpha and cada, genes encoding 2,4-dichlorophenoxyacetate (2,4-d)-degrading proteins which are characteristic of the 2,4-d-degrading bradyrhizobium sp. isolated from pristine environments, was examined by pcr and southern hybridization in several bradyrhizobium strains including type strains of bradyrhizobium japonicum usda110 and bradyrhizobium elkanii usda94, in phylogenetically closely related agromonas oligotrophica and rhodopseudomonas palustris, and in 2,4-d-degradi ...	2004	15066803
time-resolved crystallographic studies of light-induced structural changes in the photosynthetic reaction center.	light-induced structural changes in the bacterial reaction center were studied by a time-resolved crystallographic experiment. crystals of protein from blastochloris viridis (formerly rhodopseudomonas viridis) were reconstituted with ubiquinone and analyzed by monochromatic and laue diffraction, in the dark and 3 ms after illuminating the crystal with a pulsed laser (630 nm, 3 mj/pulse, 7 ns duration). refinement of monochromatic data shows that ubiquinone binds only in the "proximal" q(b) bindi ...	2004	15073325
fluorescence spectral fluctuations of single lh2 complexes from rhodopseudomonas acidophila strain 10050.	we have investigated the energy landscape of the bacterial photosynthetic peripheral light-harvesting complex lh2 of purple bacterium rhodopseudomonas acidophila by monitoring sequences of fluorescence spectra of single lh2 assemblies, at room temperature, with different excitation intensities as well as at elevated temperatures, utilizing a confocal microscope. the fluorescence peak wavelength of individual lh2 complexes was found to abruptly move between quasi-stable levels differing by up to ...	2004	15078088
single-molecule optics.	we review recent developments in single-molecule spectroscopy and microscopy. new optical methods provide access to the absorption, emission, or excitation spectra of single nano-objects and can determine either the positions of these objects with subwavelength accuracy or the full three-dimensional orientation of their transition dipole moments. recent work aims at using single molecules as nanoparts or nanoelements in a variety of molecular-scale devices, from triggered sources of single photo ...	2004	15117263
investigation of the thermal stability of porin from paracoccus denitrificans by site-directed mutagenesis and fourier transform infrared spectroscopy.	the folding of membrane proteins was addressed using outer membrane protein porin from the soil bacterium paracoccus denitrificans (p. den.). ir spectroscopy and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page) analysis were used to probe the effect of mutagenesis on the thermal stability of the protein. secondary structure analysis by amide i ir spectroscopy showed that the wild-type protein was predominantly composed of beta-sheet, which supports the x-ray crystal structure ...	2004	15137100
photoactive yellow protein, bacteriophytochrome, and sensory rhodopsin in purple phototrophic bacteria.	the purple photosynthetic bacteria contain a large variety of sensory and regulatory proteins, and those responding to light are among the most interesting. these currently include bacteriophytochrome (bph), sensory rhodopsin (sr), and photoactive yellow protein (pyp), which all appear to function as light sensors. we herein interpret new findings within the context of current knowledge. for greater detail, the reader is referred to comprehensive reviews on these topics. of the three proteins, o ...	2004	15170480
bacteriophytochrome and regulation of the synthesis of the photosynthetic apparatus in rhodopseudomonas palustris: pitfalls of using laboratory strains.	the synthesis of the photosynthetic apparatus of different strains of rhodopseudomonas palustris has been studied as a function of the oxygen concentration and far-red light. for strain cea001, only a small amount of photosynthetic apparatus is synthesized in the dark for oxygen concentration higher than 8% whereas synthesis is strongly enhanced by far-red light illumination. this enhancement is due to the action of a bacteriophytochrome (orf2127/orf2128), which antagonizes the repressor ppsr. o ...	2004	15170489
phototrophic utilization of taurine by the purple nonsulfur bacteria rhodopseudomonas palustris and rhodobacter sphaeroides.	taurine metabolism by two phototrophically grown purple nonsulfur bacteria enrichment isolates has been examined. rhodopseudomonas palustris (strain tau1) grows with taurine as a sole electron donor, sulfur and nitrogen source during photoautotrophic growth. rhodobacter sphaeroides (strain tau3) grows on the compound as sole electron donor, sulfur and nitrogen source, and partial carbon source, in the presence of co(2) during photoheterotrophic growth. both organisms utilize an inducible taurine ...	2004	15184574
evolution of function in the crotonase superfamily: the stereochemical course of the reaction catalyzed by 2-ketocyclohexanecarboxyl-coa hydrolase.	members of the mechanistically diverse enoyl-coa hydratase (crotonase) superfamily catalyze reactions that involve stabilization of an enolate anion derived from an acyl thioester of coenzyme a. 2-ketocyclohexanecarboxyl-coa hydrolase (badi), found in a pathway for anaerobic degradation of benzoate by rhodopseudomonas palustris, is a member of the crotonase superfamily that catalyzes a reverse dieckmann reaction in which the substrate is hydrolyzed to pimelyl-coa. the substrate is the configurat ...	2004	15186151
[cobalt- and chromium-containing inclusions in bacterial cells].	bacteria belonging to different taxonomic and physiological groups (members of the genera pseudomonas, brevibacterium, rhodopseudomonas, and lactococcus) are able to form intracellular cobalt- and chromium-containing magnetic inclusions. the paper deals with the structure and the intracellular localization of these inclusions and their similarity to the known noncrystalline iron-containing magnetic inclusions. the possible biological role of the magnetic inclusions is discussed.	2004	15198031
light and redox control of photosynthesis gene expression in bradyrhizobium: dual roles of two ppsr.	the two closely related bacteria bradyrhizobium and rhodopseudomonas palustris show an unusual mechanism of regulation of photosystem formation by light thanks to a bacteriophytochrome that antirepresses the regulator ppsr. in these two bacteria, we found out, unexpectedly, that two ppsr genes are present. we show that the two bradyrhizobium ppsr proteins exert antagonistic effects in the regulation of photosystem formation with a classical repressor role for ppsr2 and an unexpected activator ro ...	2004	15304477
hydrogen production from propionate by rhodopseudomonas capsulata.	hydrogen production from propionate at various concentrations by rhodopseudomonas capsulata, a purple nonsulfur bacterium, was studied at a temperature of 31 degrees c, a ph of 7.0, and an illumination intensity of 3000 lux. among the six levels of propionate, 3.84 g/l was found to be the optimum propionate concentration for h2 production in terms of substrate utilization efficiency, h2 percentage, cumulative h2 production, and h2 yield. a modified gompertz equation was able to describe properly ...	2004	15304766