Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| impact of selective excitation on carbon longitudinal relaxation: towards fast solid-state nmr techniques. | the effect of selective pulses on the apparent carbon longitudinal relaxation is investigated in three fully (13)c-labeled systems, histidine as a model system and two proteins merp and yajg. it is shown that the longitudinal relaxation of a selectively excited carbon spin is greatly enhanced, mainly because of fast spin-diffusion. this relaxation enhancement allows reducing the time necessary for polarization recovery between two experiments. this effect can be exploited either to improve the s ... | 2009 | 19576829 |
| sequence-specific bacterial growth inhibition by peptide nucleic acid targeted to the mrna binding site of 16s rrna. | peptide nucleic acid (pna) targeted to the functional domains of 23s rrna can inhibit translation and cell growth. however, effective inhibition of translation and cell growth using 16s rrna-targeted pna has still not been achieved. here, we report that pna targeted to the functional site of 16s rrna could inhibit both gene expression in vitro and bacterial growth in pure culture with sequence specificity. we used 10-mer pnas conjugated with a cell-penetrating peptide, which targeted the mrna bi ... | 2009 | 19578844 |
| tolerance of the ralstonia eutropha class i polyhydroxyalkanoate synthase for translational fusions to its c terminus reveals a new mode of functional display. | here, the class i polyhydroxyalkanoate synthase (phac) from ralstonia eutropha was investigated regarding the functionality of its conserved c-terminal region and its ability to tolerate translational fusions to its c terminus. male, the maltose binding protein, and green fluorescent protein (gfp) were considered reporter proteins to be translationally fused to the c terminus. interestingly, phac remained active only when a linker was inserted between phac and male, whereas male was not function ... | 2009 | 19581473 |
| from industrial sites to environmental applications with cupriavidus metallidurans. | cupriavidus metallidurans ch34 and related strains are adapted to metal contaminated environments. a strong resistance to environmental stressors and adaptation make it ideal strains for survival in decreasing biodiversity conditions and for bioaugmentation purposes in environmental applications. the soil bacterium c. metallidurans is able to grow chemolithoautotrophically on hydrogen and carbon dioxide allowing a strong resilience under conditions lacking organic matter. the biofilm growth on s ... | 2009 | 19582590 |
| czcp is a novel efflux system contributing to transition metal resistance in cupriavidus metallidurans ch34. | cupriavidus metallidurans ch34 possesses a multitude of metal efflux systems. here, the function of the novel p(ib4)-type atpase czcp is characterized, which belongs to the plasmid pmol30-mediated cobalt-zinc-cadmium (czc) resistance system. contribution of czcp to transition metal resistance in c. metallidurans was compared with that of three p(ib2)-type atpases (cada, znta, prba) and to other efflux proteins by construction and characterization of multiple deletion mutants. these data also yie ... | 2009 | 19602147 |
| airway infection with a novel cupriavidus species in persons with cystic fibrosis. | we describe the recovery and identification of a bacterium that represents a new species of the genus cupriavidus from cultures of respiratory tract specimens from two patients with cystic fibrosis (cf). the elucidation of the role of this species in cf lung disease will require an evaluation of a greater number of cases. | 2009 | 19605576 |
| homotaurine metabolized to 3-sulfopropanoate in cupriavidus necator h16: enzymes and genes in a patchwork pathway. | homotaurine (3-aminopropanesulfonate), a natural product and an analogue of gaba (4-aminobutyrate), was found to be a sole source of nitrogen for cupriavidus necator (ralstonia eutropha) h16, whose genome sequence is known. homotaurine nitrogen was assimilated into cell material, and the quantitative fate of the organosulfonate was sulfopropanoate, which was recovered in the growth medium. the first scalar reaction was shown to be inducible homotaurine:2-oxoglutarate aminotransferase, which rele ... | 2009 | 19648235 |
| essential role of the hprk gene in ralstonia eutropha h16. | ralstonia eutropha h16 possesses an incomplete phosphoenolpyruvate (pep):sugar phosphotransferase system (pts) composed of ei, hpr, eiia(ntr) (ptsn) and eiia(man) (ptsm). we could show that in vitro the incomplete pts phosphorylation cascade is partially functional. hpr becomes phosphorylated by pep and ei, and transfers the phosphoryl group to eiia(ntr), but only extremely slowly to eiia(man). components of this system have previously been shown to regulate the metabolism of polyhydroxybutyrate ... | 2009 | 19672046 |
| amine- and carboxyl- quantum dots affect membrane integrity of bacterium cupriavidus metallidurans ch34. | the present study examines the interaction of amine- and carboxyl- peg core/shell quantum dots (qds) with metal resistant bacterium cupriavidus metallidurans ch34. the evolution of the number of qds, their hydrodynamic radius, diffusion coefficients, and single particle fluorescence were characterized before and during the contact with bacterium by fluorescence correlation spectroscopy (fcs). the obtained results showed that at nanomolar concentrations the amine- and carboxyl-peg-qds with averag ... | 2009 | 19673316 |
| identification, biosynthesis, and characterization of polyhydroxyalkanoate copolymer consisting of 3-hydroxybutyrate and 3-hydroxy-4-methylvalerate. | in this study, we found that ralstonia eutropha strain phb(-)4 expressing the polyhydroxyalkanoate (pha) synthase 1 (phac1(ps)) from pseudomonas sp. 61-3 synthesized a pha copolymer containing a 3-hydroxybutyrate (3hb) and small amounts of 3-hydroxy-4-methylvalerate (3h4mv) and 3-hydroxyvalerate (3hv) from fructose as a sole carbon source. 3h4mv is a monomer unit that has hitherto not been reported as a naturally occurring component of phas. to increase the 3h4mv fraction in pha copolymers, the ... | 2009 | 19681605 |
| genuine genetic redundancy in maleylacetate-reductase-encoding genes involved in degradation of haloaromatic compounds by cupriavidus necator jmp134. | maleylacetate reductases (mar) are required for biodegradation of several substituted aromatic compounds. to date, the functionality of two mar-encoding genes (tfdf(i) and tfdf(ii)) has been reported in cupriavidus necator jmp134(pjp4), a known degrader of aromatic compounds. these two genes are located in tfd gene clusters involved in the turnover of 2,4-dichlorophenoxyacetate (2,4-d) and 3-chlorobenzoate (3-cb). the c. necator jmp134 genome comprises at least three other genes that putatively ... | 2009 | 19684066 |
| construction of phb and phbv multiple-gene vectors driven by an oil palm leaf-specific promoter. | one of the targets in oil palm genetic engineering programme is the production of polyhydroxybutyrate (phb) and polyhydroxybutyrate-co-valerate (phbv) in the oil palm leaf tissues. production of phb requires the use of phba (beta-ketothiolase type a), phbb (acetoacetyl-coa reductase) and phbc (phb synthase) genes of ralstonia eutropha, whereas bktb (beta-ketothiolase type b), phbb, phbc genes of r. eutropha and tdcb (threonine dehydratase) gene of escherichia coli were used for phbv production. ... | 2009 | 19699761 |
| an efflux transporter pbra and a phosphatase pbrb cooperate in a lead-resistance mechanism in bacteria. | the gene cluster pbrtrabcd from cupriavidus metallidurans ch34 is thought to encode a unique, specific resistance mechanism for lead. however, the exact functions of these genes are unknown. in this study we examine the metal specificity and functions of pbrabcd by expressing these genes in different combinations and comparing their ability to restore pb(2+), zn(2+) and cd(2+) resistance in a metal-sensitive c. metallidurans strain dn440. we show that lead resistance in c. metallidurans is achie ... | 2009 | 19737357 |
| involvement of several transcriptional regulators in the differential expression of tfd genes in cupriavidus necator jmp134. | cupriavidus necator jmp134 has been extensively studied because of its ability to degrade chloroaromatic compounds, including the herbicides 2,4-dichlorophenoxyacetic acid (2,4-d) and 3-chlorobenzoic acid (3-cb), which is achieved through the pjp4-encoded chlorocatechol degradation gene clusters: tfdcidieifi and tfddiiciieiifii. the present work describes a different tfd-genes expression profile depending on whether c. necator cells were induced with 2,4-d or 3-cb. by contrast, in vitro binding ... | 2009 | 19784929 |
| a proteomic view of the facultatively chemolithoautotrophic lifestyle of ralstonia eutropha h16. | ralstonia eutropha h16 is an h(2)-oxidizing, facultative chemolithoautotroph. using 2-de in conjunction with peptide mass spectrometry we have cataloged the soluble proteins of this bacterium during growth on different substrates: (i) h(2) and co(2), (ii) succinate and (iii) glycerol. the first and second conditions represent purely lithoautotrophic and purely organoheterotrophic nutrition, respectively. the third growth regime permits formation of the h(2)-oxidizing and co(2)-fixing systems con ... | 2009 | 19798673 |
| crystal structure and catalytic mechanism of 4-methylmuconolactone methylisomerase. | when methyl-substituted aromatic compounds are degraded via ortho (intradiol)-cleavage of 4-methylcatechol, the dead-end metabolite 4-methylmuconolactone (4-ml) is formed. degradation of 4-ml has only been described in few bacterial species, including pseudomonas reinekei mt1. the isomerization of 4-ml to 3-methylmuconolactone (3-ml) is the first step required for the mineralization of 4-ml and is catalyzed by an enzyme termed 4-methylmuconolactone methylisomerase (mlmi). we identified the gene ... | 2009 | 19801657 |
| mechanisms of gold biomineralization in the bacterium cupriavidus metallidurans. | while the role of microorganisms as main drivers of metal mobility and mineral formation under earth surface conditions is now widely accepted, the formation of secondary gold (au) is commonly attributed to abiotic processes. here we report that the biomineralization of au nanoparticles in the metallophillic bacterium cupriavidus metallidurans ch34 is the result of au-regulated gene expression leading to the energy-dependent reductive precipitation of toxic au(iii)-complexes. c. metallidurans, w ... | 2009 | 19815503 |
| site-directed mutagenesis reveals a conservation of the copper-binding site and the crucial role of his24 in coph from cupriavidus metallidurans ch34. | coph is a periplasmic copper-binding protein from cupriavidus metallidurans ch34 that contains two histidine residues. both his24 and his26 contribute to the formation of two high-affinity copper-binding sites in wild-type coph and are likely involved in a 2n2o coordination sphere in the equatorial plane. we have used site-directed mutagenesis, and a series of spectroscopic and calorimetric studies to further characterize the copper-binding sites in coph. while his24 plays a predominant role in ... | 2009 | 19857899 |
| stable isotope metabolic labeling with a novel n-enriched bacteria diet for improved proteomic analyses of mouse models for psychopathologies. | the identification of differentially regulated proteins in animal models of psychiatric diseases is essential for a comprehensive analysis of associated psychopathological processes. mass spectrometry is the most relevant method for analyzing differences in protein expression of tissue and body fluid proteomes. however, standardization of sample handling and sample-to-sample variability are problematic. stable isotope metabolic labeling of a proteome represents the gold standard for quantitative ... | 2009 | 19915716 |
| size-, composition- and shape-dependent toxicological impact of metal oxide nanoparticles and carbon nanotubes toward bacteria. | ecotoxicological effects of nanoparticles (np) are still poorly documented while their commercialization for industrial and household applications increases. the aim of this study was to evaluate the influence of physicochemical characteristics on metal oxide np and carbon nanotubes toxicological effects toward bacteria. two strains of bacteria, cupriavidus metallidurans ch34 and escherichia coli mg1655 were exposed to tio(2) or al(2)o(3) np or to multiwalled-carbon nanotubes (mwcnt). particular ... | 2009 | 19924979 |
| a kinetic and thermodynamic understanding of o2 tolerance in [nife]-hydrogenases. | in biology, rapid oxidation and evolution of h(2) is catalyzed by metalloenzymes known as hydrogenases. these enzymes have unusual active sites, consisting of iron complexed by carbonyl, cyanide, and thiolate ligands, often together with nickel, and are typically inhibited or irreversibly damaged by o(2). the knallgas bacterium ralstonia eutropha h16 (re) uses h(2) as an energy source with o(2) as a terminal electron acceptor, and its membrane-bound uptake [nife]-hydrogenase (mbh) is an importan ... | 2009 | 19934053 |
| evaluating the ability of polyhydroxyalkanoate synthase mutants to produce p(3hb-co-3ha) from soybean oil. | polyhydroxyalkanoate (pha) synthase from pseudomonas sp 61-3 (phac1(ps)) is able to synthesize p(3hb-co-3ha), consisting of a 3hb unit and medium-chain-length 3ha units of 6-12 carbon atoms. expression vectors encoding 76 phac1(ps) mutants with an amino acid replacement at position 130, 325, 477 or 481 were individually introduced into ralstonia eutropha. the mutant enzyme genes were evaluated in terms of their abilities to synthesize p(3hb-co-3ha) using soybean oil as a carbon source. 20 mutant ... | 2009 | 18798179 |
| biostructural analysis of the metal-sensor domain of cnrx from cupriavidus metallidurans ch34. | in cupriavidus metallidurans ch34, the proteins cnrx, cnry, and cnrh regulate the expression of the cnrcba operon that codes for a cation-efflux pump involved in cobalt and nickel resistance. the periplasmic part of cnrx can be defined as the metal sensor in the signal transduction complex composed of the membrane-bound anti-sigma factor cnry and the extra-cytoplasmic function sigma factor cnrh. a soluble form of cnrx was overproduced and purified. this protein behaves as a dimer in solution as ... | 2009 | 18825506 |
| cupriavidus metallidurans: evolution of a metal-resistant bacterium. | cupriavidus metallidurans ch34 has gained increasing interest as a model organism for heavy metal detoxification and for biotechnological purposes. resistance of this bacterium to transition metal cations is predominantly based on metal resistance determinants that contain genes for rnd (resistance, nodulation, and cell division protein family) proteins. these are part of transenvelope protein complexes, which seem to detoxify the periplasm by export of toxic metal cations from the periplasm to ... | 2009 | 18830684 |
| lead(ii) resistance in cupriavidus metallidurans ch34: interplay between plasmid and chromosomally-located functions. | proteome and transcriptome analysis, combined with mutagenesis, were used to better understand the response of cupriavidus metallidurans ch34 against lead(ii). structural pb(ii)-resistance genes of the pmol30-encoded pbrutrabcd operon formed the major line of defense against pb(ii). however, several general stress response mechanisms under the control of alternative sigma factors such as sigma24/rpok, sigma32/rpoh and sigma28/flia were also induced. in addition, the expression of the pbrr(2) cad ... | 2009 | 18953667 |
| genomic view of energy metabolism in ralstonia eutropha h16. | ralstonia eutropha is a strictly respiratory facultative lithoautotrophic beta-proteobacterium. in the absence of organic substrates, h2 and co2 are used as sole sources of energy and carbon. in the absence of oxygen, the organism can respire by denitrification. the recent determination of the complete genome sequence of strain h16 provides the opportunity to reconcile the results of previous physiological and biochemical studies in light of the coding capacity. these analyses revealed genes for ... | 2009 | 18957861 |
| ralstonia eutropha strain h16 as model organism for pha metabolism and for biotechnological production of technically interesting biopolymers. | the gram-negative, facultative chemolithoautotrophic bacterium ralstonia eutropha has been intensively investigated for almost 50 years. today it is the best studied 'knallgas' bacterium and producer of poly(3-hydroxybutyric acid). this polyester provides the basis for renewable resource-based biodegradable plastic materials and has attracted much biotechnological interest. the polymer is accumulated in large amounts in the cell and can be used for various applications ranging from replacement o ... | 2009 | 18957865 |
| the genome organization of ralstonia eutropha strain h16 and related species of the burkholderiaceae. | ralstonia eutropha strain h16 is a facultatively chemolithoautotrophic, hydrogen-oxidizing bacterium belonging to the family burkholderiaceae of the betaproteobacteria. the genome of r. eutropha h16 consists of two chromosomes (chr1, chr2) and one megaplasmid (phg1), and thus shows a multi-replicon architecture, which is characteristic for all members of the burkholderiaceae sequenced so far. the genes for housekeeping cell functions are located on chr1. in contrast, many characteristic traits o ... | 2009 | 18957867 |
| on-line characterization of physiological state in poly(beta-hydroxybutyrate) production by wautersia eutropha. | culture fluorescence measurement technique has the potential for on-line characterization of metabolic status of fermentation processes. many fluorophores present inside the living cells such as nadh + h+, tryptophan, pyridoxine, and riboflavin fluoresce at specific excitation and emission wavelength combinations. since these key intracellular metabolites are involved in cell growth and metabolism, their concentration change at any time inside the cell could reflect the changes in cell metabolic ... | 2009 | 18958410 |
| burkholderia spp. are the most competitive symbionts of mimosa, particularly under n-limited conditions. | bacteria isolated from mimosa nodules in taiwan, papua new guinea, mexico and puerto rico were identified as belonging to either the alpha- or beta-proteobacteria. the beta-proteobacterial burkholderia and cupriavidus strains formed effective symbioses with the common invasive species mimosa diplotricha, m. pigra and m. pudica, but the alpha-proteobacterial rhizobium etli and r. tropici strains produced a range of symbiotic phenotypes from no nodulation through ineffective to effective nodulatio ... | 2009 | 19040456 |
| monitoring catalysis of the membrane-bound hydrogenase from ralstonia eutropha h16 by surface-enhanced ir absorption spectroscopy. | 2009 | 19067445 | |
| effect of anaerobic promoters on the microaerobic production of polyhydroxybutyrate (phb) in recombinant escherichia coli. | nine anaerobic promoters were cloned and constructed upstream of phb synthesis genes phbcab from ralstonia eutropha for the micro- or anaerobic phb production in recombinant escherichia coli. among the promoters, the one for alcohol dehydrogenase (padhe) was found most effective. recombinant e. coli jm 109 (pwcy09) harboring padhe and phbcab achieved a 48% phb accumulation in the cell dry weight after 48 h of static culture compared with only 30% phb production under its native promoter. sixty-s ... | 2009 | 19107470 |
| the abc-transporter atma is involved in nickel and cobalt resistance of cupriavidus metallidurans strain ch34. | cupriavidus metallidurans ch34 genome contains an ortholog of atm1p named atma (rmet_0391, yp_582546). in saccharomyces cerevisiae, the abc-type transport system atm1p is involved in export of iron-sulfur clusters from mitochondria into the cytoplasm for assembly of cytoplasmic iron-sulfur containing proteins. an atma mutant of c. metallidurans was sensitive to nickel and cobalt but not iron cations. atma increased also resistance to these cations in escherichia coli strains that carry deletions ... | 2009 | 19132541 |
| toxicity assessment upon augmented biostimulation source to indigenous rhizobium cupriavidus taiwanensis. | this novel-attempt study used chemostat pulse technique (cpt) and transient dynamics of dissolved oxygen (do) in cstr to quantify stimulating or inhibitory effects of augmented nutrient sources in the presence of phenol upon cupriavidus taiwanensis r186. with injected augmented nutrients, phenol degradation performance of r186 was directly dependent on combined toxicity between phenol and the augmented substrate and the biodegradability of phenol. the findings indicated that although phenol was ... | 2009 | 18684558 |
| a beta-barrel outer membrane protein facilitates cellular uptake of polychlorophenols in cupriavidus necator. | the tcprxabcyd operon of cupriavidus necator jmp134 is involved in the degradation of 2,4,6-trichlorophenol (tcp). all of the gene products except tcpy have assigned functions in tcp metabolism. sequence comparison identified tcpy as a member of cog4313, a group of hypothetical proteins. tcpy has a signal peptide, indicating it is a membrane or secreted protein. secondary structure and topology analysis indicated tcpy as a beta-barrel outer membrane protein, similar to the escherichia coli outer ... | 2010 | 19937267 |
| biosynthesis of polylactic acid and its copolymers using evolved propionate coa transferase and pha synthase. | for the synthesis of polylactic acid (pla) and its copolymers by one-step fermentation process, heterologous pathways involving clostridium propionicum propionate coa transferase (pct(cp)) and pseudomonas sp. mbel 6-19 polyhydroxyalkanoate (pha) synthase 1 (phac1(ps6-19)) were introduced into escherichia coli for the generation of lactyl-coa endogenously and incorporation of lactyl-coa into the polymer, respectively. since the wild-type phac1(ps6-19) did not efficiently accept lactyl-coa as a su ... | 2010 | 19937726 |
| metabolic engineering of escherichia coli for the production of polylactic acid and its copolymers. | polylactic acid (pla) is a promising biomass-derived polymer, but is currently synthesized by a two-step process: fermentative production of lactic acid followed by chemical polymerization. here we report production of pla homopolymer and its copolymer, poly(3-hydroxybutyrate-co-lactate), p(3hb-co-la), by direct fermentation of metabolically engineered escherichia coli. as shown in an accompanying paper, introduction of the heterologous metabolic pathways involving engineered propionate coa-tran ... | 2010 | 19937727 |
| enhanced polyhydroxybutyrate (phb) production via the coexpressed phacab and vgb genes controlled by arabinose p promoter in escherichia coli. | to develop an approach to enhance polyhydroxybutyrate (phb) production via the coexpressed phacab and vgb genes controlled by arabinose p(bad) promoter in escherichia coli. | 2010 | 19943886 |
| unravelling the c3/c4 carbon metabolism in ralstonia eutropha h16. | detailed knowledge about the enzymes responsible for conversion of c(3) and c(4) compounds will be helpful to establish the bacterial strain ralstonia eutropha as platform for the production of biotechnologically interesting compounds. although various studies about these enzymes were accomplished in the past, some contradicting information about the enzyme pattern in this bacterium still exists. to resolve these discrepancies, the c(3) /c(4) metabolism was reinvestigated after the genome sequen ... | 2010 | 20002867 |
| cupriavidus pampae sp. nov., a novel herbicide-degrading bacterium isolated from agricultural soil. | a bacterial consortium able to degrade the herbicide 4-(2,4-dichlorophenoxy) butyric acid (2,4-db) was obtained from an agricultural soil of the argentinean humid pampa region which has a history of long-term herbicide use. four bacterial strains were isolated from the consortium and identified as members of the genera cupriavidus, labrys and pseudomonas. a polyphasic systematic analysis was carried out on strain cpdb6(t), the member of the 2,4-db-degrading consortium able to degrade 2,4-db as a ... | 2010 | 20023053 |
| modeling of p-nitrophenol biodegradation by ralstonia eutropha via application of the substrate inhibition concept. | in this study, the capability of ralstonia eutropha h16 to degrade p-nitrophenol with or without a supplementary substrate (glucose or yeast extract) was investigated. using pnp as the sole energy and carbon source, the biodegradation behavior of the bacterium was modeled by applying a modified form of the monod equation that considers substrate inhibition, as suggested in the literature (mu=(mu(m)s/k(s) +s)(1-(s/s(m)(n)). pnp at a 6 mg/l initial level was degraded within 20h under the defined i ... | 2010 | 20061083 |
| fatal infection caused by cupriavidus gilardii in a child with aplastic anemia. | cupriavidus gilardii is a gram-negative bacterium that has rarely been associated with human infections. we report a fatal case of sepsis caused by c. gilardii in a previously healthy 12-year-old female. | 2010 | 20071544 |
| experimental evolution of a plant pathogen into a legume symbiont. | rhizobia are phylogenetically disparate alpha- and beta-proteobacteria that have achieved the environmentally essential function of fixing atmospheric nitrogen in symbiosis with legumes. ample evidence indicates that horizontal transfer of symbiotic plasmids/islands has played a crucial role in rhizobia evolution. however, adaptive mechanisms that allow the recipient genomes to express symbiotic traits are unknown. here, we report on the experimental evolution of a pathogenic ralstonia solanacea ... | 2010 | 20084095 |
| evidence for conformational changes upon copper binding to cupriavidus metallidurans czce. | czce is a periplasmic protein from cupriavidus metallidurans ch34 that can bind four copper atoms per dimer. we have crystallized the apo form of the protein and determined its structure at 1.85 a resolution. three cu atoms were localized by soaking apo-czce crystals into a cucl(2) solution. we identified his24 as a cu(ii) ligand in each protomer and asp100 as a key residue for cu binding at the interface of the dimer. the role of these amino acids was confirmed by site-directed mutagenesis and ... | 2010 | 20112954 |
| statistical medium optimization and biodegradative capacity of ralstonia eutropha toward p-nitrophenol. | the effect of p-nitrophenol (pnp) concentration with or without glucose and yeast extract on the growth and biodegradative capacity of ralstonia eutropha was examined. the chemical constituents of the culture medium were modeled using a response surface methodology. the experiments were performed according to the central composite design arrangement considering pnp, glucose and yeast extract as the selected variables whose influences on the degradation was evaluated (shaking in reciprocal mode, ... | 2010 | 20140697 |
| 2,3-dihydroxypropane-1-sulfonate degraded by cupriavidus pinatubonensis jmp134: purification of dihydroxypropanesulfonate 3-dehydrogenase. | 2,3-dihydroxypropane-1-sulfonate (dhps) is a widespread intermediate in plant and algal transformations of sulfoquinovose (sq) from the plant sulfolipid sulfoquinovosyl diacylglycerol. further, dhps is recovered quantitatively during bacterial degradation of sq by klebsiella sp. strain abr11. dhps is also a putative precursor of sulfolactate in e.g. ruegeria pomeroyi dss-3. a bioinformatic approach indicated that some 28 organisms with sequenced genomes might degrade dhps inducibly via sulfolact ... | 2010 | 20150239 |
| requirements for construction of a functional hybrid complex of photosystem i and [nife]-hydrogenase. | the development of cellular systems in which the enzyme hydrogenase is efficiently coupled to the oxygenic photosynthesis apparatus represents an attractive avenue to produce h(2) sustainably from light and water. here we describe the molecular design of the individual components required for the direct coupling of the o(2)-tolerant membrane-bound hydrogenase (mbh) from ralstonia eutropha h16 to the acceptor site of photosystem i (ps i) from synechocystis sp. pcc 6803. by genetic engineering, th ... | 2010 | 20154103 |
| application of polyhydroxyalkanoate granules for sizing of paper. | polyhydroxyalkanoates (phas) are characterized by the chemistry of the biodegradable inclusions inside the microbial membrane. they are produced by a wide variety of bacteria, where they function as energy and carbon storage materials. this intracellular bioplastic forms a stable latex suitable for surface treatments of paper such as sizing and coating. in this work, we compare native granules and artificial granules made from market poly(3-hydroxybutyrate) (phb) and poly(3-hydroxybutyrate-co-hy ... | 2010 | 20155934 |
| comparison of the membrane-bound [nife] hydrogenases from r. eutropha h16 and d. vulgaris miyazaki f in the oxidized ready state by pulsed epr. | the geometric and electronic structures of the active sites in the oxidized ni(r)-b state of the [nife] hydrogenases from ralstonia eutropha h16 and desulfovibrio vulgaris miyazaki f were investigated in pulsed epr and endor experiments at two different microwave frequencies (x- and q-band). two hyperfine-couplings were clearly resolved in the frozen solution spectra arising from the beta-protons of the nickel-coordinating cysteine residues cys549 and cys586 from the desulfovibrio vulgaris and r ... | 2010 | 20165762 |
| bacterial deposition of gold on hair: archeological, forensic and toxicological implications. | trace metal analyses in hair are used in archeological, forensic and toxicological investigations as proxies for metabolic processes. we show metallophilic bacteria mediating the deposition of gold (au), used as tracer for microbial activity in hair post mortem after burial, affecting results of such analyses. | 2010 | 20174476 |
| h2 conversion in the presence of o2 as performed by the membrane-bound [nife]-hydrogenase of ralstonia eutropha. | [nife]-hydrogenases catalyze the oxidation of h(2) to protons and electrons. this reversible reaction is based on a complex interplay of metal cofactors including the ni-fe active site and several [fe-s] clusters. h(2) catalysis of most [nife]-hydrogenases is sensitive to dioxygen. however, some bacteria contain hydrogenases that activate h(2) even in the presence of o(2). there is now compelling evidence that o(2) affects hydrogenase on three levels: 1) h(2) catalysis, 2) hydrogenase maturation ... | 2010 | 20186906 |
| copk from cupriavidus metallidurans ch34 binds cu(i) in a tetrathioether site: characterization by x-ray absorption and nmr spectroscopy. | cupriavidus metallidurans ch34 is a bacterium that is resistant to high metal concentrations in the environment. increased copper resistance is associated with the cop cluster on the large plasmid pmol30 that is composed of at least 21 genes. the copk gene encodes a 74 residue periplasmic protein whose expression is strongly upregulated in the presence of copper. copk was previously shown to cooperatively bind cu(i) and cu(ii) in distinct, specific sites. the solution structure of cu(i)-copk and ... | 2010 | 20192263 |
| identification and characterization of the furfural and 5-(hydroxymethyl)furfural degradation pathways of cupriavidus basilensis hmf14. | the toxic fermentation inhibitors in lignocellulosic hydrolysates pose significant problems for the production of second-generation biofuels and biochemicals. among these inhibitors, 5-(hydroxymethyl)furfural (hmf) and furfural are specifically notorious. in this study, we describe the complete molecular identification and characterization of the pathway by which cupriavidus basilensis hmf14 metabolizes hmf and furfural. the identification of this pathway enabled the construction of an hmf and f ... | 2010 | 20194784 |
| gene clusters involved in isethionate degradation by terrestrial and marine bacteria. | ubiquitous isethionate (2-hydroxyethanesulfonate) is dissimilated by diverse bacteria. growth of cupriavidus necator h16 with isethionate was observed, as was inducible membrane-bound isethionate dehydrogenase (isej) and inducible transcription of the genes predicted to encode isej and a transporter (iseu). biodiversity in isethionate transport genes was observed and investigated by transcription experiments. | 2010 | 19933343 |
| a new concept for reduction of diffuse contamination by simultaneous application of pesticide and pesticide-degrading microorganisms. | pesticide residues and their transformation products are frequently found in groundwater and surface waters. this study examined whether adding pesticide-degrading microorganisms simultaneously with the pesticide at application could significantly reduce diffuse contamination from pesticide use. degradation of the phenoxyacetic acid herbicides mcpa (4-chloro-2-methylphenoxyacetic acid) and 2,4-d (2,4-dichlorophenoxyacetic acid) was studied in soil microcosm experiments after simultaneous sprayin ... | 2010 | 19557524 |
| production of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) from unrelated carbon sources by metabolically engineered escherichia coli. | a metabolically engineered escherichia coli has been constructed for the production of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [p(3hb-co-4hb)] from unrelated carbon sources. genes involved in succinate degradation in clostridium kluyveri and p(3hb) accumulation pathway of ralstonia eutropha were co-expressed for the synthesis of the above copolyester. e. coli native succinate semialdehyde dehydrogenase genes sad and gabd were both deleted for eliminating succinate formation from succinate s ... | 2010 | 20304089 |
| use of controlled exogenous stress for improvement of poly(3-hydroxybutyrate) production in cupriavidus necator. | the phb production by cupriavidus necator h16 depends on the type and concentration of stress factors and on the time of stress application. hydrogen peroxide and ethanol significantly enhanced phb accumulation in c. necator cells. improved yields (10.9 g/l phb) were observed after exposure of bacterial culture to 0.5 mmol/l h2o2 at the beginning of cultivation and to additional peroxide stress (5 mmol/l h2o2) after 60 h of cultivation (beginning of the stationary phase). production was then app ... | 2010 | 20336499 |
| the complete multipartite genome sequence of cupriavidus necator jmp134, a versatile pollutant degrader. | cupriavidus necator jmp134 is a gram-negative beta-proteobacterium able to grow on a variety of aromatic and chloroaromatic compounds as its sole carbon and energy source. | 2010 | 20339589 |
| protein-protein complex formation affects the ni-fe and fe-s centers in the h2-sensing regulatory hydrogenase from ralstonia eutropha h16. | the regulatory ni-fe hydrogenase (rh) from the h(2)-oxidizing bacterium ralstonia eutropha functions as an oxygen-resistant hydrogen sensor, which is composed of the large, active-site-containing hoxc subunit and the small subunit hoxb carrying fe-s clusters. in vivo, the hoxbc subunits form a dimer designated as rh(wt). the rh(wt) protein transmits its signals to the histidine protein kinase hoxj, which itself forms a homotetramer and a stable complex with rh(wt) (rh(wt)-hoxj(wt)), located in t ... | 2010 | 20340124 |
| efficient whole-cell biotransformation of 5-(hydroxymethyl)furfural into fdca, 2,5-furandicarboxylic acid. | 2,5-furandicarboxylic acid (fdca) is a promising bio-based platform chemical that may serve as a 'green' substitute for terephthalate in polyesters. recently, a novel hmf/furfural oxidoreductase from cupriavidus basilensis hmf14 was identified that converts 5-(hydroxymethyl)furfural (hmf) into fdca. the hmfh gene encoding this oxidoreductase was introduced into pseudomonas putida s12 and the resulting whole-cell biocatalyst was employed to produce fdca from hmf. in fed-batch experiments using gl ... | 2010 | 20363622 |
| impact of amino acid substitutions near the catalytic site on the spectral properties of an o2-tolerant membrane-bound [nife] hydrogenase. | [nife] hydrogenases are widespread among microorganisms and catalyze the reversible cleavage of molecular hydrogen. however, only a few bacteria, such as ralstonia eutropha h16 (re), synthesize [nife] hydrogenases that perform h(2) cycling in the presence of o(2). these enzymes are of special interest for biotechnological applications. to gain further insight into the mechanism(s) responsible for the remarkable o(2) tolerance, we employ ftir and epr spectroscopy to study mutant variants of the m ... | 2010 | 20376875 |
| crystallization and preliminary x-ray crystallographic analysis of the [nife]-hydrogenase maturation factor hypf1 from ralstonia eutropha h16. | the hydrogenase maturation factor hypf1 is a truncated but functional version of the hypf protein. hypf is known to be involved in the supply of the cn(-) ligands of the active site of [nife]-hydrogenases, utilizing carbamoyl phosphate as a substrate. the first crystallization and preliminary x-ray studies of hypf1 from ralstonia eutropha h16 are reported here. crystals of hypf1 (394 amino acids, 40.7 kda) were obtained by the sitting-drop vapour-diffusion technique using sodium formate as a pre ... | 2010 | 20383020 |
| characterization of mnpc, a hydroquinone dioxygenase likely involved in the meta-nitrophenol degradation by cupriavidus necator jmp134. | cupriavidus necator jmp134 utilizes meta-nitrophenol (mnp) as the sole source of carbon, nitrogen, and energy. the metabolic reconstruction of mnp degradation performed in silico suggested that mnpc might have played an important role in mnp degradation. in order to experimentally confirm the prediction, we have now characterized the mnpc-encoded (amino)hydroquinone dioxygenase involved in the ring-cleavage reaction of mnp degradation. real-time pcr analysis indicated that mnpc played an essenti ... | 2010 | 20386911 |
| differential proteomic analysis using isotope-coded protein-labeling strategies: comparison, improvements and application to simulated microgravity effect on cupriavidus metallidurans ch34. | among differential proteomic methods based on stable isotopic labeling, isotope-coded protein labeling (icpl) is a recent non-isobaric technique devised to label primary amines found in proteins. icpl overcomes some of the disadvantages found in other chemical-labeling techniques, such as itraq or icat. however, previous analyses revealed that more than 30% of the proteins identified in regular icpl generally remain unquantified. in this study, we describe a modified version of icpl, named post- ... | 2010 | 20391527 |
| [cloning and molecular organization of the polyhydroxyalkanoic acid synthase gene (phac) of ralstonia eutropha strain b5786]. | class i polyhydroxyalkanoic acid (pha) synthase gene (phac) of ralstonia eutropha strain b5786 was cloned and characterized. r. eutropha b5786 features the ability to synthesize multicomponent phas with short- and medium-chain-length monomers from simple carbohydrate substrate. a correlation was made between the molecular structure of pha synthase and substrate specificity and the ability of strain-producers to accumulate phas of this or that structure. a strong similarity of pha synthase of r. ... | 2010 | 20391757 |
| genome-wide transcriptome analyses of the 'knallgas' bacterium ralstonia eutropha h16 with regard to polyhydroxyalkanoate metabolism. | ralstonia eutropha h16 is probably the best-studied 'knallgas' bacterium and producer of poly(3-hydroxybutyrate) (phb). genome-wide transcriptome analyses were employed to detect genes that are differentially transcribed during phb biosynthesis. for this purpose, four transcriptomes from different growth phases of the wild-type h16 and of the two phb-negative mutants phb(-)4 and delta phac1 were compared: (i) cells from the exponential growth phase with cells that were in transition to stationar ... | 2010 | 20395272 |
| biofilms formed on humic substances: response to flow conditions and carbon concentrations. | stream biofilms are exposed to dynamic conditions of flow velocity and organic carbon availability. thus, the aim of this study was to investigate the response of biofilms formed with and without humic substances (hss) to an increase in flow velocity (0.04-0.10 ms(-1)) and hss concentration (9.7+/-1.0 to 19.8+/-0.4 mgl(-1) c). the highest amount of biofilm, measured as volatile suspended solids and total countable cells, was observed at 0.10 m s(-1) without hss. the bacterial community compositi ... | 2010 | 20413305 |
| mineralization of pcbs by the genetically modified strain cupriavidus necator jms34 and its application for bioremediation of pcbs in soil. | polychlorobiphenyls (pcbs) are classified as "high-priority pollutants." diverse microorganisms are able to degrade pcbs. however, bacterial degradation of pcbs is generally incomplete, leading to the accumulation of chlorobenzoates (cbas) as dead-end metabolites. to obtain a microorganism able to mineralize pcb congeners, the bph locus of burkholderia xenovorans lb400, which encodes one of the most effective pcb degradation pathways, was incorporated into the genome of the cba-degrading bacteri ... | 2010 | 20414654 |
| chain transfer reaction catalyzed by various polyhydroxyalkanoate synthases with poly(ethylene glycol) as an exogenous chain transfer agent. | polyhydroxyalkanoate (pha) synthases catalyze chain transfer (ct) reaction after polymerization reaction of pha by transferring pha chain from pha synthase to a ct agent, resulting in covalent bonding of ct agent to pha chain at the carboxyl end. previous studies have shown that poly(ethylene glycol) (peg) is an effective exogenous ct agent. this study aimed to compare the effects of peg on ct reaction during poly[(r)-3-hydroxybutyrate] [p(3hb)] synthesis by using six pha synthases in escherichi ... | 2010 | 20422180 |
| implantable cardiac defibrillator pocket infection due to a previously undescribed cupriavidus species. | the genus cupriavidus consists of gram-negative, nonfermenting bacteria most of which are environmental organisms, though some species have been associated with human disease. we report the recovery and identification of an isolate that represents a previously undescribed species of cupriavidus from an implantable cardiac defibrillator pocket infection. | 2010 | 20427695 |
| comonomer compositional distribution, physical properties, and enzymatic degradability of bacterial poly(3-hydroxybutyrate-co-3-hydroxy-4-methylvalerate) copolyesters. | poly(3-hydroxybutyrate-co-3-hydroxy-4-methylvalerate) (p(3hb-co-3h4mv)) was synthesized by using ralstonia eutropha strain phb(-)4 (pha-negative mutant) harboring with the n149s/d171g double mutation of pha synthase gene from aeromonas caviae (phac(ac) nsdg mutant) with 4-methylvaleric acid and fructose as the carbon sources. because the microbially synthesized p(3hb-co-3h4mv) samples were found to have broad comonomer compositional distribution, p(3hb-co-3h4mv) samples with 3h4mv content of 7, ... | 2010 | 20441146 |
| pseudo-outbreak of cupriavidus pauculus infection at an outpatient clinic related to rinsing culturette swabs in tap water. | cupriavidus pauculus is a water microorganism rarely isolated from clinical specimens. we describe a pseudo-outbreak in which multiple strains that were associated with moistening of culturette swabs with tap water were isolated from a single clinic before collecting the patient specimen. | 2010 | 20444965 |
| a new shuttle vector for gene expression in biopolymer-producing ralstonia eutropha. | ralstonia eutropha (formerly alcaligenes eutrophus) is a fascinating microorganism with a great scientific importance and an immense commercial potential. a new genetic transformation system for the organism would greatly facilitate the biological study and molecular engineering of this organism. we report here a versatile gene expression method for the genetic engineering of r. eutropha. this method, based on a simplified electroporation protocol, uses a recombinant plasmid, pbs29-p2, containin ... | 2010 | 20447426 |
| [a case of ventilator-associated pneumonia caused by cupriavidus pauculus]. | cupriavidus pauculus (formerly cdc group ivc-2) is a non-fermentative, motile, gram-negative bacillus, rarely associated with human infections. it has been isolated from water, water from ultrafiltration systems and bottled mineral water. to date, 19 cases of bacteremia, two cases of peritonitis and one case of tenosynovitis associated with c. pauculus have been reported in english literature. in this paper, we report the first case of c. pauculus ventilator-associated pneumonia (vap) in turkey. ... | 2010 | 20455409 |
| isolation of phylogenetically diverse nonylphenol ethoxylate-degrading bacteria and characterization of their corresponding biotransformation pathways. | most nonylphenol ethoxylate (npeo)-degrading isolates have been assigned to gamma-proteobacteria, which is different from the results acquired by using molecular ecological techniques. to better understand the environmental fate of npeos, bacterial isolation strategy characterized by the use of gellan gum as a gelling reagent and a low concentration of target carbon source were used to isolate phylogenetically diverse npeo-degrading bacteria from activated sludge, and the biotransformation pathw ... | 2010 | 20457466 |
| the complete genome sequence of cupriavidus metallidurans strain ch34, a master survivalist in harsh and anthropogenic environments. | many bacteria in the environment have adapted to the presence of toxic heavy metals. over the last 30 years, this heavy metal tolerance was the subject of extensive research. the bacterium cupriavidus metallidurans strain ch34, originally isolated by us in 1976 from a metal processing factory, is considered a major model organism in this field because it withstands milli-molar range concentrations of over 20 different heavy metal ions. this tolerance is mostly achieved by rapid ion efflux but al ... | 2010 | 20463976 |
| isolation and characterization of fenamiphos degrading bacteria. | the biological factors responsible for the microbial breakdown of the organophosphorus nematicide fenamiphos were investigated. microorganisms responsible for the enhanced degradation of fenamiphos were isolated from soil that had a long application history of this nematicide. bacteria proved to be the most important group of microbes responsible for the fenamiphos biodegradation process. seventeen bacterial isolates utilized the pure active ingredient fenamiphos as a carbon source. sixteen isol ... | 2010 | 20464454 |
| modeling of cd uptake and efflux kinetics in metal-resistant bacterium cupriavidus metallidurans. | the model of uptake with instantaneous adsorption and efflux, muiae, describing and predicting the overall cd uptake by the metal-resistant bacterium cupriavidus metallidurans ch34, is presented. muiae takes into account different processes at the bacteria-medium interface with specific emphasis on the uptake and efflux kinetics and the decrease in bulk metal concentration. a single set of eight parameters provides a reasonable description of experimentally determined adsorbed and internalized c ... | 2010 | 20491434 |
| formation of palladium(0) nanoparticles at microbial surfaces. | the increasing demand and limited natural resources for industrially important platinum-group metal (pgm) catalysts render the recovery from secondary sources such as industrial waste economically interesting. in the process of palladium (pd) recovery, microorganisms have revealed a strong potential. hitherto, bacteria with the property of dissimilatory metal reduction have been in focus, although the biochemical reactions linking enzymatic pd(ii) reduction and pd(0) deposition have not yet been ... | 2010 | 20506339 |
| characterization of catabolic meta-nitrophenol nitroreductase from cupriavidus necator jmp134. | cupriavidus necator jmp134 utilizes meta-nitrophenol (mnp) as a sole source of carbon, nitrogen, and energy. the metabolic reconstruction of mnp degradation performed in silico suggested that the mnp cluster might have played important roles in mnp degradation. in order to experimentally confirm the prediction, we have now characterized mnpa-encoded meta-nitrophenol nitroreductase involved in the initial reaction of mnp degradation. real-time pcr analysis indicated that mnpa played an essential ... | 2010 | 20508930 |
| separation of pha-accumulating cells in activated sludge based on differences in buoyant density. | 2010 | 20513964 | |
| a metal-repressed promoter from gram-positive bacillus subtilis is highly active and metal-induced in gram-negative cupriavidus metallidurans. | a synthetic version of the metal-regulated gene a (mrga) promoter from bacillus subtilis, which in this gram-positive bacterium is negatively regulated by manganese, iron, cobalt, or copper turned out to promote high level of basal gene expression that is further enhanced by co(ii), cd(ii), mn(ii), zn(ii), cu(ii), or ni(ii), when cloned in the gram-negative bacterium cupriavidus metallidurans. promoter activity was monitored by expression of the reporter gene coding for the enhanced green fluore ... | 2010 | 20517979 |
| polyphasic analysis of the bacterial community in the rhizosphere and roots of cyperus rotundus l. grown in a petroleum-contaminated soil. | cyperus rotundus l. is a perennial herb which was found prevailing in an area in the northeast of brazil previously contaminated with petroleum. in order to enlarge the knowledge of microorganism-plant interaction in phytoremediation, the bacterial community present in the rhizosphere and roots of c. rotundus was evaluated by culture-dependent and molecular approaches. pcr-dgge analyses based on the 16s rrna gene showed that the profiles of bulk soil, rhizosphere and root samples had a high degr ... | 2010 | 20519908 |
| metal-induced conformational changes in zneb suggest an active role of membrane fusion proteins in efflux resistance systems. | resistance nodulation cell division (rnd)-based efflux complexes mediate multidrug and heavy-metal resistance in many gram-negative bacteria. efflux of toxic compounds is driven by membrane proton/substrate antiporters (rnd protein) in the plasma membrane, linked by a membrane fusion protein (mfp) to an outer-membrane protein. the three-component complex forms an efflux system that spans the entire cell envelope. the mfp is required for the assembly of this complex and is proposed to play an imp ... | 2010 | 20534468 |
| optimization of growth media components for polyhydroxyalkanoate (pha) production from organic acids by ralstonia eutropha. | we employed systematic mixture analysis to determine optimal levels of acetate, propionate, and butyrate for cell growth and polyhydroxyalkanoate (pha) production by ralstonia eutropha h16. butyrate was the preferred acid for robust cell growth and high pha production. the 3-hydroxyvalerate content in the resulting pha depended on the proportion of propionate initially present in the growth medium. the proportion of acetate dramatically affected the final ph of the growth medium. a model was con ... | 2010 | 20535466 |
| polyhydroxyalkanoates production by engineered cupriavidus necator from waste material containing lactose. | cupriavidus necator dsm 545 is a well-known polyhydroxyalkanoates (phas) producer, but unable to grow on lactose. the aim of this study was to construct a recombinant strain of c. necator that can use lactose-containing waste material such as cheese whey, to produce phas. one of the intracellular pha depolymerases (phaz1) of c. necator was chosen to insert the lacz, laci and laco genes of escherichia coli. this would have the effect to allow polymer production on lactose and, at the same time, t ... | 2010 | 20537531 |
| efficacy of various chemical disinfectants on biofilms formed in spacecraft potable water system components. | as the provision of potable water is critical for successful habitation of the international space station (iss), life support systems were installed in december 2008 to recycle both humidity from the atmosphere and urine to conserve available water in the station. in-flight pre-consumption testing from the dispensing needle at the potable water dispenser (pwd) indicated that bacterial concentrations exceeded the current iss specifications of 50 colony-forming units (cfu) ml(-1). subsequent inve ... | 2010 | 20544435 |
| functional expression of phacab genes from cupriavidus taiwanensis strain 184 in escherichia coli for polyhydroxybutyrate production. | polyhydroxyalkanoates are polyesters synthesized by numerous microorganisms. these polyesters are biodegradable and have similar properties to those of conventional plastics. cupriavidus taiwanensis strain 184 is phylogenetically related to the well-known polyhydroxybutyrate (phb) producer ralstonia eutropha (cupriavidus necator) and is also shown to be able to accumulate significant amounts of phb. in this study, we cloned the phb synthesis genes (phacab) from c. taiwanensis 184 into escherichi ... | 2010 | 20556541 |
| expression and single-step purification of mercury transporter (mert) from cupriavidus metallidurans in e. coli. | the mercury transporter, mert, from cupriavidus metallidurans was cloned into prset-c and expressed in various e. coli hosts. expression of mert gene failed in common expression hosts like e. coli bl21(de3), e. coli bl21(de3)plyss and e. coli gj1158 due to expression induced toxicity. the protein was successfully expressed in e. coli c43(de3) as inclusion bodies. the inclusion bodies were solubilized with triton x-100 detergent. the detergent solubilized protein with n-terminal his-tag was purif ... | 2010 | 20574829 |
| in vivo enzyme immobilization by inclusion body display. | a novel strategy for in vivo immobilization of enzymes on the surfaces of inclusion bodies has been established. it relies on expression in escherichia coli of the polyhydroxybutyrate synthase phac from cupriavidus necator, which carries at its amino terminus an engineered negatively charged alpha-helical coil (ecoil) and forms inclusion bodies upon high-level expression. coexpression in the same cell of galactose oxidase (goase) from fusarium spp. carrying a carboxy-terminal positively charged ... | 2010 | 20581198 |
| impact of multiple beta-ketothiolase deletion mutations in ralstonia eutropha h16 on the composition of 3-mercaptopropionic acid-containing copolymers. | beta-ketothiolases catalyze the first step of poly(3-hydroxybutyrate) [poly(3hb)] synthesis in bacteria by condensing two molecules of acetyl coenzyme a (acetyl-coa) to acetoacetyl-coa. analyses of the genome sequence of ralstonia eutropha h16 revealed 15 isoenzymes of phaa in this bacterium. in this study, we generated knockout mutants of various phaa homologues to investigate their role in and contributions to poly(3hb) metabolism and to suppress biosynthesis of 3hb-coa for obtaining enhanced ... | 2010 | 20601511 |
| development of a gene knockout system for ralstonia eutropha h16 based on the broad-host-range vector expressing a mobile group ii intron. | ralstonia eutropha h16 is a gram-negative lithoautotrophic bacterium and is one of the best biopolymer-producing bacteria. it can grow to high cell densities either under lithoautotrophic or under heterotrophic conditions, which makes it suitable for a number of biotechnological applications. also, r. eutropha h16 can degrade various aromatic compounds for environmental applications. the mobile group ii intron can be used for the rapid and specific disruption of various bacterial genes by insert ... | 2010 | 20608980 |
| comprehensive analysis of an antarctic bacterial community with the adaptability of growth at higher temperatures than those in antarctica. | to investigate the adaptability to higher temperatures of antarctic microorganisms persisting in low temperature conditions for a long time, antarctic lake samples were incubated in several selection media at 25 degrees c and 30 degrees c. the microorganisms did not grow at 30 degrees c; however, some of them grew at 25 degrees c, indicating that the bacteria in antarctic have the ability to grow at a wide range of temperatures. total dna was extracted from these microorganisms and amplified usi ... | 2010 | 20616433 |
| reaction engineering studies for the production of 2-hydroxyisobutyric acid with recombinant cupriavidus necator h 16. | recombinant cupriavidus necator h 16 with a novel metabolic pathway using a cobalamin-dependent mutase was exploited to produce 2-hydroxyisobutyric acid (2-hiba) from renewable resources through microbial fermentation. 2-hiba production capacities of different strains of c. necator h 16 deficient in the phb synthase gene and genetically engineered to enable the production of 2-hiba from the intracellular phb precursor (r)-3-hydroxybutyryl-coa were evaluated in 48 parallel milliliter-scale stirre ... | 2010 | 20625719 |
| environmentally benign recovery and reactivation of palladium from industrial waste by using gram-negative bacteria. | 2010 | 20652926 | |
| [characteristics of proteins synthesized by hydrogen-oxidizing microorganisms]. | the study was conducted to determine the biological value of proteins synthesized by hydrogen-oxidizing microorganisms--the hydrogen bacteria alcaligenes eutrophus z1 and ralstonia eutropha b5786 and the co-resistant strain of carboxydobacterium seliberia carboxydohydrogena z1062. based on a number of significant parameters characterizing the biological value of a product, the proteins of hydrogen-oxidizing microorganisms have been found to occupy an intermediate position between traditional ani ... | 2010 | 21261071 |
| isolation and characterization of cupriavidus basilensis hmf14 for biological removal of inhibitors from lignocellulosic hydrolysate. | the formation of toxic fermentation inhibitors such as furfural and 5-hydroxy-2-methylfurfural (hmf) during acid (pre-)treatment of lignocellulose, calls for the efficient removal of these compounds. lignocellulosic hydrolysates can be efficiently detoxified biologically with microorganisms that specifically metabolize the fermentation inhibitors while preserving the sugars for subsequent use by the fermentation host. the bacterium cupriavidus basilensis hmf14 was isolated from enrichment cultur ... | 2010 | 21255332 |
| highly selective l-threonine 3-dehydrogenase from cupriavidus necator and its use in determination of l-threonine. | l-threonine level in blood plasma is a biomarker of some diseases and nitrogen imbalance in the body. the determination of l-threonine is interesting and is required for diagnosis and management of inherited metabolic disorder. this is the first report of the specific enzymatic determination of l-threonine by a newly discovered l-threonine 3-dehydrogenase (thrdh, ec 1.1.1.103) from cupriavidus necator nbrc 102504. thrdh, a key enzyme in l-threonine catabolism in microorganisms and animals, catal ... | 2010 | 21073854 |
| characterization of phosphate solubilizing bacteria in sediments from a shallow eutrophic lake and a wetland: isolation, molecular identification and phosphorus release ability determination. | the transformation of phosphorus (p) is a major factor of lake eutrophication, and phosphate releasing bacteria play an important role in the release process. experiments were conducted to investigate p content and characterize phosphate solubilizing bacterial composition at the molecular level in a shallow eutrophic lake and a wetland. results showed that p concentrations were relatively high and derived from agricultural runoff and domestic or industrial pollution. enumeration and molecular id ... | 2010 | 21102378 |
| first case of invasive human infection caused by cupriavidus metallidurans. | we describe the first case of invasive human infection (a nosocomial septicemia) caused by cupriavidus metallidurans. this metal-resistant bacterium has not been reported to be pathogenic in humans or animals. | 2010 | 21106795 |