Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| 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 |
| 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 |
| enhanced production of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) copolymer with manipulated variables and its properties. | cupriavidus sp. usmaa1020, a local isolate was able to biosynthesis poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [p(3hb-co-4hb)] copolymer with various 4hb precursors as the sole carbon source. manipulation of the culture conditions such as cell concentration, phosphate ratio and culture aeration significantly affected the synthesis of p(3hb-co-4hb) copolymer and 4hb composition. p(3hb-co-4hb) copolymer with 4hb compositions ranging from 23 to 75 mol% 4hb with various mechanical and thermal prop ... | 2009 | 19189144 |
| enhanced selenate accumulation in cupriavidus metallidurans ch34 does not trigger a detoxification pathway. | cupriavidus metallidurans ch34 cells grown under sulfate-limited conditions accumulated up to six times more selenate than cells grown in sulfate-rich medium. the products of selenate reduction detected by x-ray absorption spectroscopy, electron microscopy, and energy-dispersive x-ray analysis did not define this strain as being a good candidate for bioremediation of selenate-contaminated environments. | 2009 | 19201966 |
| one-step production of immobilized alpha-amylase in recombinant escherichia coli. | industrial enzymes are often immobilized via chemical cross-linking onto solid supports to enhance stability and facilitate repeated use in bioreactors. for starch-degrading enzymes, immobilization usually places constraints on enzymatic conversion due to the limited diffusion of the macromolecular substrate through available supports. this study describes the one-step immobilization of a highly thermostable alpha-amylase (bla) from bacillus licheniformis and its functional display on the surfac ... | 2009 | 19201981 |
| chimeric enzyme composed of polyhydroxyalkanoate (pha) synthases from ralstonia eutropha and aeromonas caviae enhances production of phas in recombinant escherichia coli. | chimeric enzymes composed of polyhydroxyalkanoate (pha) synthases from ralstonia eutropha (cupriavidus necator) (phac(re)) and aeromonas caviae (phac(ac)) were constructed. phac(re) is known for its potent enzymatic activity among the characterized pha synthases. phacac has broad substrate specificity and synthesizes short-chain-length (scl)/medium-chain-length (mcl) pha. we attempted to create chimeric enzymes inheriting both of the advantageous properties. among eight chimeras, acre12, with 26 ... | 2009 | 19226108 |
| unprecedented binding cooperativity between cu(i) and cu(ii) in the copper resistance protein copk from cupriavidus metallidurans ch34: implications from structural studies by nmr spectroscopy and x-ray crystallography. | the bacterium cupriavidus metallidurans ch34 is resistant to high environmental concentrations of many metal ions, including copper. this ability arises primarily from the presence of a large plasmid pmol30 which includes a cluster of 19 cop genes that respond to copper. one of the protein products copk is induced at high levels and is expressed to the periplasm as a small soluble protein (8.3 kda). apo-copk associates in solution to form a dimer (k(d) approximately 10(-5) m) whose structure was ... | 2009 | 19236095 |
| arsr arsenic-resistance regulatory protein from cupriavidus metallidurans ch34. | the cupriavidus metallidurans ch34 arsr gene, which is part of the arsric(2)bc(1)hp operon, and its putative arsenic-resistance regulatory protein were identified and characterized. the arsenic-induced transcriptome of c. metallidurans ch34 showed that the genes most upregulated in the presence of arsenate were all located within the ars operon, with none of the other numerous heavy metal resistance systems present in ch34 being induced. a transcriptional fusion between the luxcdabe operon and t ... | 2009 | 19238575 |
| plasmids captured in c. metallidurans ch34: defining the proma family of broad-host-range plasmids. | the self-transmissible, broad-host-range (bhr) plasmid pmol98 was previously isolated from polluted soil using a triparental plasmid capture approach and shown to possess a replicon similar to that of the bhr plasmids psb102 and pipo2. here, complete sequence analysis and comparative genomics reveal that the 55.5 kb nucleotide sequence of pmol98 shows extensive sequence similarity and synteny with the bhr plasmid family that now includes pipo2, psb102, pter331, and pmrad02. they share a plasmid ... | 2009 | 19259779 |
| production of short-chain-length/medium-chain-length polyhydroxyalkanoate (pha) copolymer in the plastid of arabidopsis thaliana using an engineered 3-ketoacyl-acyl carrier protein synthase iii. | short-chain-length/medium-chain-length (scl/mcl) polyhydroxyalkanoate (pha) was produced in the plastids of arabidopsis thaliana. phe87thr (f87t) mutated 3-ketoacyl-acyl carrier protein (acp) synthase iii (fabh) from escherichia coli , and ser325thr/gln481lys (st/qk) mutated polyhydroxyalkanoate (pha) synthase (phac1) from pseudomonas sp. 61-3, along with the beta-ketothiolase (phaa) and acetoacetyl-coa reductase (phab) from ralstonia eutropha (cupriavidus necator) genes were introduced into ara ... | 2009 | 19265441 |
| microbial synthesis of poly((r)-3-hydroxybutyrate-co-3-hydroxypropionate) from unrelated carbon sources by engineered cupriavidus necator. | cupriavidus necator was engineered aiming to synthesize poly[(r)-3-hydroxybutyrate-co-3-hydroxypropionate] copolyester, p(3hb-co-3hp), from structurally unrelated carbon sources without addition of any precursor compounds. we modified a metabolic pathway in c. necator for generation of 3-hydroxypropionyl-coa (3hp-coa) by introducing malonyl-coa reductase and the 3hp-coa synthetase domain of trifunctional propionyl-coa synthase; both members of the 3-hydroxypropionate cycle, a novel co(2)-fixatio ... | 2009 | 19267466 |
| use of a microchip electrophoresis system for estimation of bacterial phylogeny and analysis of no3- reducing bacterial flora in field soils. | phylogenetic estimation method without determination of dna sequence was developed. by this method, fragment length polymorphism separately digested with multiple restriction enzymes was measured using microchip electrophoresis and affiliated with those calculated from corresponding dna sequence in the theoretical database. the phylogenies of 129 no(3)(-) reducing bacteria newly isolated from field soils were estimated by this method, and were compared to those by carbon source utilization profi ... | 2009 | 19270404 |
| diverse protein regulations on pha formation in ralstonia eutropha on short chain organic acids. | organic acids are considered as potential substrates for biosynthesis of polyhydroxyalkaonates. the acids may also be the metabolic inhibitors at moderate concentration levels. in this study, ralstonia eutropha was used to elucidate the protein regulations when the bacterial cells pre-cultivated on glucose were exposed to three representative short chain organic acids, acetic, propionic and levulinic acids. the research compared and examined the proteins that might participate in pha metabolism, ... | 2009 | 19270755 |
| optimal exponential feeding strategy for dual-substrate biostimulation of phenol degradation using cupriavidus taiwanensis. | the exponential feeding strategy (efs) of dual substrates (i.e., phenol and glycerol) was applied to optimize the overall performance of phenol degradation by cupriavidus taiwanensis r186. addition of a second substrate (e.g., glycerol) could stimulate the phenol biodegradation efficiency of strain r186. hence, a feasible efs was developed for fed-batch phenol biodegradation using the dual-substrate biostimulation technique. the phenol degradation kinetics was well characterized with proposed mo ... | 2009 | 19285800 |
| spectroscopic insights into the oxygen-tolerant membrane-associated [nife] hydrogenase of ralstonia eutropha h16. | this study provides the first spectroscopic characterization of the membrane-bound oxygen-tolerant [nife] hydrogenase (mbh) from ralstonia eutropha h16 in its natural environment, the cytoplasmic membrane. the h2-converting mbh is composed of a large subunit, harboring the [nife] active site, and a small subunit, capable in coordinating one [3fe4s] and two [4fe4s] clusters. the hydrogenase dimer is electronically connected to a membrane-integral cytochrome b. epr and fourier transform infrared s ... | 2009 | 19304663 |
| genetic and phenotypic diversity of fenitrothion-degrading bacteria isolated from soils. | twenty-seven fenitrothion-degrading bacteria were isolated from different soils, and their genetic and phenotypic characteristics were investigated. analysis of the 16s rdna sequence showed that the isolates were related to members of the genera burkholderia, pseudomonas, sphingomonas, cupriavidus, corynebacterium, and arthrobacter. among the 27 isolates, 12 different chromosomal dna fingerprinting patterns were obtained by polymerase chain reaction (pcr) amplification of repetitive extragenic p ... | 2009 | 19307758 |
| screening of strain-specific actinobacillus pleuropneumoniae genes using a combination method. | we describe a three-step method designed to identify distinct antigen-coding genes between two related bacterial genomes by: (a) constructing a subtractive library using representational difference analysis (rda), (b) characterization of gene expression in vitro using a ribosome display system combined with antibody screening and (c) gene recovery and confirmation using rt-pcr and reverse southern hybridization, respectively. to test the efficacy of this strategy we screened the antigen-coding g ... | 2009 | 19318057 |
| conversion of volatile fatty acids into polyhydroxyalkanoate by ralstonia eutropha. | the aims of this study were to optimize condensed corn solubles (ccs) as a medium for growth of ralstonia eutropha and to determine the effects of individual volatile fatty acids (vfas) on polyhydroxyalkanoate (pha) production. | 2009 | 19320958 |
| [the cnr-like operon in strain comamonas sp. encoding resistance to cobalt and nickel]. | plasmid pbs501 was detected in the strain comamonas sp. bs501. this plasmid specifies high level of induced resistance (5 mm) to cobalt/nickel both in the host strain and in related strains c. testosteroni b-1241 and c. acidovorans b-1251. hybridization analysis revealed a homology of pbs501 restriction fragments with the only well-characterized operon cnrxyhcbat that resides in plasmid pmol28 from cupriavidus metallidurans ch34. essential differences in the structural organization of the cobalt ... | 2009 | 19382684 |
| comparative metagenomics of daphnia symbionts. | shotgun sequences of dna extracts from whole organisms allow a comprehensive assessment of possible symbionts. the current project makes use of four shotgun datasets from three species of the planktonic freshwater crustaceans daphnia: one dataset from clones of d. pulex and d. pulicaria and two datasets from one clone of d. magna. we analyzed these datasets with three aims: first, we search for bacterial symbionts, which are present in all three species. second, we search for evidence for cyanob ... | 2009 | 19383155 |
| new mobile genetic elements in cupriavidus metallidurans ch34, their possible roles and occurrence in other bacteria. | cupriavidus metallidurans strain ch34 is a beta-proteobacterium that thrives in low concentrations of heavy metals. the genetic determinants of resistance to heavy metals are located on its two chromosomes, and are particularly abundant in the two megaplasmids, pmol28 and pmol30. we explored the involvement of mobile genetic elements in acquiring these and others traits that might be advantageous in this strain using genome comparison of cupriavidus/ralstonia strains and related beta-proteobacte ... | 2009 | 19390985 |
| isolation and characterization of a phorate degrading bacterium. | to study the degradation of phorate by a bacterium isolated from phorate-contaminated sites. | 2009 | 19413758 |
| building macroporous materials from microgels and microbes via one-step cryogelation. | macroporous materials are prepared from microgels or microbes by one-step chemical cross-linking under semifrozen conditions. this avoids the use of freeze drying of the sample because a chemically stable structure is prepared under semifrozen conditions. cryostructuration results in a material with pore walls composed of closely packed particles. | 2009 | 19419137 |
| high yield synthesis of 12-aminolauric acid by "enzymatic transcrystallization" of omega-laurolactam using omega-laurolactam hydrolase from acidovorax sp. t31. | the genes encoding omega-laurolactam hydrolases from cupriavidus sp. t7, acidovorax sp. t31, cupriavidus sp. u124, and sphingomonas sp. u238 were cloned and sequenced. nucleotide and amino acid sequence analysis of the four genes indicated that the primary structures of these omega-laurolactam hydrolases are significantly similar to the 6-aminohexanoate-cyclic-dimer hydrolase (ec 3.5.2.12). these genes were expressed in escherichia coli, and the omega-laurolactam hydrolysing activity of the reco ... | 2009 | 19420719 |
| 3-chlorobenzoate is taken up by a chromosomally encoded transport system in cupriavidus necator jmp134. | cupriavidus necator jmp134(pjp4) is able to grow on 3-chlorobenzoate (3-cb), a model chloroaromatic pollutant. catabolism of 3-cb is achieved via the expression of the chromosomally encoded benabcd genes and the tfd genes from plasmid pjp4. since passive diffusion of benzoic acid derivatives at physiological ph is negligible, the uptake of this compound should be facilitated by a transport system. however, no transporter has so far been described to perform this function, and identification of c ... | 2009 | 19423632 |
| intracellular excision and reintegration dynamics of the iceclc genomic island of pseudomonas knackmussii sp. strain b13. | genomic islands are dna elements acquired by horizontal gene transfer that are common to a large number of bacterial genomes, which can contribute specific adaptive functions, e.g. virulence, metabolic capacities or antibiotic resistances. some genomic islands are still self-transferable and display an intricate life-style, reminiscent of both bacteriophages and conjugative plasmids. here we studied the dynamical process of genomic island excision and intracellular reintegration using the integr ... | 2009 | 19432799 |
| biosorption equilibria of binary cd(ii) and ni(ii) systems onto saccharomyces cerevisiae and ralstonia eutropha cells: application of response surface methodology. | present study investigated the biosorption of cd(ii) and ni(ii) from aqueous solution onto saccharomyces cerevisiae and ralstonia eutropha non-living biomass. biomass inactivated by heat and pretreated by ethanol was used in determination of optimum conditions. the important process parameters, such as initial solution ph (2-8), initial ni(ii) concentration (11-42 mg/l), initial cd(ii) concentration (11-42 mg/l), and biomass dosage (0.2-4.7 g/l) were optimized using design of experiments (doe). ... | 2009 | 19443115 |
| production of functionalized biopolyester granules by recombinant lactococcus lactis. | many bacteria are naturally capable of accumulating biopolyesters composed of 3-hydroxy fatty acids as intracellular inclusions, which serve as storage granules. recently, these inclusions have been considered as nano-/microbeads with surface-attached proteins, which can be engineered to display various protein-based functions that are suitable for biotechnological and biomedical applications. in this study, the food-grade, generally-regarded-as-safe gram-positive organism lactococcus lactis was ... | 2009 | 19465535 |
| stable expression of the chlorocatechol dioxygenase gene from ralstonia eutropha nh9 in hybrid poplar cells. | the cbna gene encoding chlorocatechol dioxygenase from the soil bacterium ralstonia eutropha nh9 under the control of a modified cauliflower mosaic virus 35s promoter was introduced into a hybrid poplar (populus tremula x p. tremuloides). integration of the cbna gene in transgenic poplar was confirmed by pcr and genomic southern blot analysis. expression of the cbna gene was analyzed by western blot analysis. transgenic poplar calli efficiently converted 3-chlorocatechol to 2-chloro-cis,cis-muco ... | 2009 | 19502754 |
| detection of polyhydroxyalkanoate synthase activity on a polyacrylamide gel. | this study presents a method to detect active polyhydroxyalkanoate (pha) synthase on a polyacrylamide gel that combines the polyhydroxybutyrate (phb) polymerization reaction with sudan black b staining. after separation of the protein samples on a modified sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page), the slab gel was submerged in a buffer containing beta-hydroxybutyryl-coenzyme a (3-hbcoa) as substrate and incubated at room temperature for in vitro phb polymerization. th ... | 2009 | 19527674 |
| introduction to a special festschrift issue celebrating the microbiology of cupriavidus metallidurans strain ch34. | 2009 | 19551487 | |
| altered composition of ralstonia eutropha poly(hydroxyalkanoate) through expression of pha synthase from allochromatium vinosum atcc 35206. | the class iii poly(hydroxyalkanoate) synthase (phas) genes (phac and phae) of a photosynthetic bacterium, allochromatium vinosum atcc 35206, were cloned, sequenced and expressed in a heterologous host. pcr coupled with a chromosomal gene-walking method was used to clone and subsequently sequence the contiguous phac (1,068 bps) and phae (1,065 bps) genes of a. vinosum atcc 35206. blastp search of protein databases showed that the gene-products of phac and phae are different (<66% identities) from ... | 2009 | 19557308 |
| expression and regulation of ribulose 1,5-bisphosphate carboxylase/oxygenase genes in mycobacterium sp. strain jc1 dsm 3803. | ribulose 1,5-bisphosphate carboxylase/oxygenase (rubisco) is the key enzyme of the calvin reductive pentose phosphate cycle. two sets of structural genes (cbbls-1 and -2) for form i rubisco have been previously identified in the mycobacterium sp. strain jc1, which is able to grow on carbon monoxide (co) or methanol as sole sources of carbon and energy. northern blot and reverse transcriptase pcr showed that the cbbls-1 and -2 genes are expressed in cells grown on either carbon monoxide (co) or m ... | 2009 | 19557347 |
| matrix-assisted laser desorption ionization-time of flight mass spectrometry for identification of nonfermenting gram-negative bacilli isolated from cystic fibrosis patients. | the identification of nonfermenting gram-negative bacilli isolated from cystic fibrosis (cf) patients is usually achieved by using phenotype-based techniques and eventually molecular tools. these techniques remain time-consuming, expensive, and technically demanding. we used a method based on matrix-assisted laser desorption ionization-time of flight mass spectrometry (maldi-tof-ms) for the identification of these bacteria. a set of reference strains belonging to 58 species of clinically relevan ... | 2008 | 18685005 |
| the screening, characterization, and use of omega-laurolactam hydrolase: a new enzymatic synthesis of 12-aminolauric acid. | several omega-laurolactam degrading microorganisms were isolated from soil samples. these strains were capable of growing in a medium containing omega-laurolactam as sole source of carbon and nitrogen. among them, five strains (t7, t31, u124, u224, and u238) were identified as cupriavidus sp. t7, acidovorax sp. t31, cupriavidus sp. u124, rhodococcus sp. u224, and sphingomonas sp. u238, respectively. the omega-laurolactam hydrolyzing enzyme from rhodococcus sp. u224 was purified to homogeneity, a ... | 2008 | 18685217 |
| metabolic reconstruction of aromatic compounds degradation from the genome of the amazing pollutant-degrading bacterium cupriavidus necator jmp134. | cupriavidus necator jmp134 is a model for chloroaromatics biodegradation, capable of mineralizing 2,4-d, halobenzoates, chlorophenols and nitrophenols, among other aromatic compounds. we performed the metabolic reconstruction of aromatics degradation, linking the catabolic abilities predicted in silico from the complete genome sequence with the range of compounds that support growth of this bacterium. of the 140 aromatic compounds tested, 60 serve as a sole carbon and energy source for this stra ... | 2008 | 18691224 |
| characterization of new isolated ralstonia eutropha strain a-04 and kinetic study of biodegradable copolyester poly(3-hydroxybutyrate-co-4-hydroxybutyrate) production. | a new isolated bacterial strain a-04 capable of producing high content of polyhydroxyalkanoates (phas) was morphologically and taxonomically identified based on biochemical tests and 16s rrna gene analysis. the isolate is a member of the genus ralstonia and close to ralstonia eutropha. hence, this study has led to the finding of a new and unexplored r. eutropha strain a-04 capable of producing phas with reasonable yield. the kinetic study of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [p(3hb-co ... | 2008 | 18712546 |
| characterization of biofilm formation on a humic material. | biofilms are major sites of carbon cycling in streams. therefore, it is crucial to improve knowledge about biofilms' structure and microbial composition to understand their contribution in the self-purification of surface water. the present work intends to study biofilm formation in the presence of humic substances (hss) as a carbon source. two biofilm flowcells were operated in parallel; one with synthetic stream water, displaying a background carbon concentration of 1.26+/-0.84 mg l(-1), the o ... | 2008 | 18712549 |
| expression of copa and cusa in shewanella during copper stress. | copper homeostasis is tightly regulated in all living cells as a result of the necessity and toxicity of this metal in free cationic form. in gram-negative bacteria cpx-type atpases (e.g. copa in escherichia coli) and heavy-metal efflux rnd proteins (e.g. cusa in e. coli) play an important role in transport of copper across the cytoplasmic and outer membrane. we investigated the expression of cusa- and copa-like proteins in shewanella oneidensis mr1 and shewanella strain mb4, a mn(iv)-reducing i ... | 2008 | 18757804 |
| isolation of dieldrin- and endrin-degrading bacteria using 1,2-epoxycyclohexane as a structural analog of both compounds. | this report describes the selective isolation of dieldrin- and endrin-degrading bacteria from soil with high degradation activity toward dieldrin and endrin. several enrichment cultures from the soil were arranged with several structural analogs of dieldrin and endrin as a growth substrate and examined for their degradation activities toward dieldrin and endrin. an enrichment culture with 1,2-epoxycyclohexane (ech) was found to aerobically degrade dieldrin and endrin. denaturing gradient gel ele ... | 2008 | 18769917 |
| polyhydroxyalkanoate film formation and synthase activity during in vitro and in situ polymerization on hydrophobic surfaces. | in vitro and in situ enzymatic polymerization of polyhydroxyalkanoate (pha) on two hydrophobic surfaces, a highly oriented pyrolytic graphite (hopg) and an alkanethiol self-assembled monolayer (sam), was studied by atomic force microscopy (afm) and quartz crystal microbalance (qcm), using purified ralstonia eutropha pha synthase (phac(re)) as a biocatalyst. (r)-specific enoyl-coa hydratase was used to prepare r-enantiomer monomers [(r)-3-hydroxyacyl-coa] with an acyl chain length of 4-6 carbon a ... | 2008 | 18771315 |
| biosynthesis of polyhydroxyalkanoate copolymers from mixtures of plant oils and 3-hydroxyvalerate precursors. | the combination of plant oils and 3-hydroxyvalerate (3hv) precursors were evaluated for the biosynthesis of polyhydroxyalkanoate (pha) copolymers containing 3hv monomers by cupriavidus necator h16. among various mixtures of plant oils and 3hv-precursors, the mixture of palm kernel oil and sodium propionate was suitable for the biosynthesis of high concentration of pha (6.8gl(-1)) containing 7mol% of 3hv. the 3hv monomer composition can be regulated in the range of 0-23mol% by changing culture pa ... | 2008 | 18325764 |
| quantifying the surface characteristics and flocculability of ralstonia eutropha. | the microbial surface and flocculability were qualitatively characterized through the combination of the surface thermodynamic and the extended dlvo approaches, with ralstonia eutropha, a polyhydroxybutyrate-producing bacterium, as an example. the negativity of the zeta potential of r. eutropha decreased from the initial -19.5 to -11 mv in its cultivation with the consumption of glucose. the total interfacial free energy (deltagadh) was changed from -80 to 28.5 mj m(-2) in its entire growth proc ... | 2008 | 18347792 |
| protein engineering of streptavidin for in vivo assembly of streptavidin beads. | escherichia coli was engineered to intracellularly manufacture streptavidin beads. variants of streptavidin (monomeric, core and mature full length streptavidin) were c-terminally fused to phac, the polyester granule forming enzyme of cupriavidus necator. all streptavidin fusion proteins mediated formation of the respective granules in e. coli and were overproduced at the granule surface. the monomeric streptavidin showed biotin binding (0.7 ng biotin/microg bead protein) only when fused as sing ... | 2008 | 18367283 |
| isolation and characterization of new cyclohexylacetic acid-degrading bacteria. | six cyclohexylacetic acid-degrading strains were isolated from soil samples in japan and identified as members of the genera cupriavidus (strain kua-1), rhodococcus, and dietzia by 16s rrna gene sequence analysis. for the first time members of these genera were shown to be capable of degrading cyclohexylacetic acid. a selected strain, kua-1, which is the first reported gram-negative organism capable of growth on cyclohexylacetic acid, was identified as a cupriavidus metallidurans, based on morph ... | 2008 | 18392890 |
| uv mutagenesis of cupriavidus necator for extracellular production of (r)-3-hydroxybutyric acid. | ultraviolet (uv) mutagenesis was carried out to obtain mutant strains of cupriavidus necator that could produce (r)-3-hydroxybutyric acid [(r)-3-hb] in the culture supernatant. | 2008 | 18399978 |
| redox-controlled dinitrosyl formation at the diiron-oxo center of nora. | in the denitrifying bacterium ralstonia eutropha h16, the nora protein is coproduced with the respiratory nitric oxide (no) reductase. nora contains a diiron-oxo center, which can form stable adducts with dioxygen and no. in contrast to other diiron proteins, the formation of nora-no requires both fully reduced protein and additional electrons. a minor fraction of in vitro nora-no represents a paramagnetic dinitrosyl iron complex (dnic), while the major fraction is attributed to a dnic of the st ... | 2008 | 18433625 |
| biosynthesis of enantiopure (s)-3-hydroxybutyric acid in metabolically engineered escherichia coli. | a biosynthetic pathway for the production of (s)-3-hydroxybutyric acid (s3hb) from glucose was established in recombinant escherichia coli by introducing the beta-ketothiolase gene from ralstonia eutropha h16, the (s)-3-hydroxybutyryl-coa dehydrogenase gene from r. eutropha h16, or clostridium acetobutylicum atcc824, and the 3-hydroxyisobutyryl-coa hydrolase gene from bacillus cereus atcc14579. artificial operon consisting of these genes was constructed and was expressed in e. coli bl21 (de3) co ... | 2008 | 18461320 |
| microbial utilization and biopolyester synthesis of bagasse hydrolysates. | cellulosic biomass is a potentially inexpensive renewable feedstock for the biorefineries of fuels, chemicals and materials. sugarcane bagasse was pretreated in dilute acid solution under moderately severe conditions, releasing sugars and other hydrolysates including volatile organic acids, furfurals and acid soluble lignin. utilization of the hydrolysates by an aerobic bacterium, ralstonia eutropha, was investigated to determine if the organic inhibitors can be removed for potential recycling a ... | 2008 | 18474421 |
| genome sequence of the beta-rhizobium cupriavidus taiwanensis and comparative genomics of rhizobia. | we report the first complete genome sequence of a beta-proteobacterial nitrogen-fixing symbiont of legumes, cupriavidus taiwanensis lmg19424. the genome consists of two chromosomes of size 3.42 mb and 2.50 mb, and a large symbiotic plasmid of 0.56 mb. the c. taiwanensis genome displays an unexpected high similarity with the genome of the saprophytic bacterium c. eutrophus h16, despite being 0.94 mb smaller. both organisms harbor two chromosomes with large regions of synteny interspersed by speci ... | 2008 | 18490699 |
| molecular structure and metal-binding properties of the periplasmic copk protein expressed in cupriavidus metallidurans ch34 during copper challenge. | the copk gene is localized on the pmol30 plasmid of cupriavidus metallidurans ch34 within the complex cop cluster of genes, for which 21 genes have been identified. the expression of the corresponding periplasmic copk protein is strongly upregulated in the presence of copper, leading to a high periplasmic accumulation. the structure and metal-binding properties of copk were investigated by nmr and mass spectrometry. the protein is dimeric in the apo state with a dissociation constant in the rang ... | 2008 | 18533181 |
| factors influencing the release of mitragyna speciosa crude extracts from biodegradable p(3hb-co-4hb). | copolyesters of 3-hydroxybutyrate (3hb) and 4-hydroxybutyrate (4hb) were produced by cupriavidus sp. (usmaa2-4) (dsm 19379) from carbon sources of 1,4-butanediol and gamma-butyrolactone. the composition of copolyesters produced varied from 0 to 45 mol% 4hb, depending on the combination of carbon sources supplied. the p(3hb-co-4hb) films containing mitragyna speciosa crude extract were prepared with the ratio varying from 10 to 40% (w/w). the in vitro crude extract release of the films was studie ... | 2008 | 18584978 |
| [cupriavidus pauculus isolation in the intensive care unit]. | 2008 | 18588825 | |
| x-ray structure of the metal-sensor cnrx in both the apo- and copper-bound forms. | both the x-ray structures of the apo- and the copper-bound forms of the metal-sensor domain (residues 31-148) of cnrx from cupriavidus metallidurans ch34 were obtained at 1.74a resolution from a selenomethionine derivative. this four-helix hooked-hairpin is the first structure of a metal-sensor in an ecf-type signaling pathway. the copper ion is bound in a type 2-like center with a 3n1o coordination in the equatorial plane and shows an unprecedented remote fifth axial ligand with met93 contribut ... | 2008 | 18992246 |
| degradation behaviors of nonylphenol ethoxylates by isolated bacteria using improved isolation method. | nonylphenol ethoxylate (npeo)-degrading bacteria were isolated from activated sludge using an improved isolation method, and the corresponding degradation behaviours were investigated. eight npeo-degrading strains distributed in genera pseudomonas, sphingomonas, sphingobium, cupriavidus, ralstonia, achromobacter, and staphylococcus were acquired. the latter five genera have never been reported for the degradation of npeos. four degradation patterns were observed for the eight pure strains. in pa ... | 2008 | 19143306 |
| [beta-proteorhizobia and nonrhizobial species--a review]. | the terms alpha- and beta-rhizobia were proposed to distinguish the rhizobial alpha- and beta-proteorhizobia respectively. in this review we present recently development of rhizobial taxonomy about beta-rhizobia in the genus burkholeria, cupriavidus isolated from mimosa and alpha-proteorhizobia belonging to methylobacterium, devosia, ochrobactrum, phyllobacterium and blastobacter lineage. furthermore, we also introduced the evolution of symbiosis related genes such as noda and nifh, and posed so ... | 2008 | 19160827 |
| production and characterization of poly-(3-hydroxybutyrate) from recombinant escherichia coli grown on cheap renewable carbon substrates. | although the biopolymer poly-(3-hydroxybutyrate), p[3hb], presents physicochemical properties that make it an alternative material to conventional plastics, its biotechnological production is quite expensive. as carbon substrates contribute greatly to p[3hb] production cost, the utilization of a cheaper carbon substrate and less demanding micro-organisms should decrease its cost. in the present study a 2(3) factorial experimental design was applied, aiming to evaluate the effects of using hydrol ... | 2008 | 19039071 |
| fed-batch cultivation of wautersia eutropha. | batch kinetics of polyhydroxybutyrate (phb) synthesis in a bioreactor under controlled conditions of ph and dissolved oxygen gave a biomass of 14 g l(-1) with a phb concentration of 6.1 g l(-1) in 60 h. the data of the batch kinetics was used to develop a mathematical model, which was then extrapolated to fed-batch by incorporating the dilution due to substrate feeding. offline computer simulation of the fed-batch model was done to develop the nutrient feeding strategies in the fed-batch cultiva ... | 2008 | 17532211 |
| combined effects of external mass transfer and biodegradation rates on removal of phenol by immobilized ralstonia eutropha in a packed bed reactor. | biodegradation of phenol by calcium-alginate immobilized ralstonia eutropha was carried out in a batch stirred and a packed bed reactor. in the batch system studies, the effect of initial phenol concentration on biodegradation was investigated at 30 degrees c and ph 7 while in the continuous system studies, the effects of flow rate and inlet phenol concentration on biodegradation were tested at the same temperature and ph. the observed biodegradation rate constant was calculated at different flo ... | 2008 | 17611023 |
| metal biosorption capability of cupriavidus taiwanensis and its effects on heavy metal removal by nodulated mimosa pudica. | a novel metal biosorption system consisting of the symbiotic combination of an indigenous metal-resistant rhizobial strain, cupriavidus taiwanensis tj208, and its host plant mimosa pudica has been developed for the removal of heavy-metal pollutants. free-living c. taiwanensis tj208 cells were able to adsorb 50.1, 19.0, and 19.6 mg/g of pb, cu, and cd, respectively. after nodulation via inoculation with strain tj208, the metal uptake ability of m. pudica markedly increased, as the nodulated m. pu ... | 2008 | 17624667 |
| mechanisms of bacterial resistance to chromium compounds. | chromium is a non-essential and well-known toxic metal for microorganisms and plants. the widespread industrial use of this heavy metal has caused it to be considered as a serious environmental pollutant. chromium exists in nature as two main species, the trivalent form, cr(iii), which is relatively innocuous, and the hexavalent form, cr(vi), considered a more toxic species. at the intracellular level, however, cr(iii) seems to be responsible for most toxic effects of chromium. cr(vi) is usually ... | 2008 | 17934697 |
| mobility and recalcitrance of organo-chromium(iii) complexes. | hexavalent chromium [cr(vi)] is a major industrial pollutant. bioremediation of cr(vi) to cr(iii) is a viable clean-up approach. however, cr(vi) bioreduction also produces soluble organo-cr(iii) complexes, and little is known about their behavior in the environment. when tested with soil columns, citrate-cr(iii) showed little sorption to soil; malate-cr(iii) had limited partitioning with soil; and histidine-cr(iii) exhibited significant interaction with soil. it appears that the mobility varies ... | 2008 | 17959226 |
| treatment of arsenic contaminated water in a batch reactor by using ralstonia eutropha mtcc 2487 and granular activated carbon. | this paper presents the observations on the bio-removal of arsenic from contaminated water by using ralstonia eutropha mtcc 2487 and activated carbon in a batch reactor. the effects of agitation time, ph, type of granular activated carbon (gac) and initial arsenic concentration (as(o)) on the % removal of arsenic have been discussed. under the experimental conditions, optimum removal was obtained at the ph of 6-7 with agitation time of 100 h. the % removal of as(t) increased initially with the i ... | 2008 | 17980486 |
| biosynthesis of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) copolymer by cupriavidus sp. usmaa1020 isolated from lake kulim, malaysia. | cupriavidus sp. usmaa1020 was isolated from malaysian environment and able to synthesize poly(3-hydroxybutyrate-co-4-hydroxybutyrate), [p(3hb-co-4hb)] when grown on gamma-butyrolactone as the sole carbon source. the polyester was purified from freeze-dried cells and analyzed by nuclear magnetic resonance (nmr) spectroscopy. 1h and 13c nmr results confirmed the presence of 3hb and 4hb monomers. in a one-step cultivation process, p(3hb-co-4hb) accumulation by cupriavidus sp. usmaa1020 was affected ... | 2008 | 17981028 |
| phap is involved in the formation of a network on the surface of polyhydroxyalkanoate inclusions in cupriavidus necator h16. | polyhydroxyalkanoate (pha) inclusions are polymeric storage inclusions formed in some bacterial species when carbon levels are high but levels of another essential nutrient, such as nitrogen, are low. though much is known about pha synthesis, little is known about inclusion structure. in this study, atomic force microscopy (afm) was employed to elucidate the structure of pha inclusions at the nanoscale level, including the characterization of different layers of structure. afm data suggest that ... | 2008 | 17981962 |
| czce from cupriavidus metallidurans ch34 is a copper-binding protein. | czce is encoded by the most distal gene of the czc determinant that allows cupriavidus metallidurans ch34 to modulate its internal concentrations of cobalt, zinc and cadmium by regulation of the expression of the efflux pump czccba. we have overproduced and purified czce. czce is a periplasm-located dimeric protein able to bind specifically 4 cu-equivalent per dimer. spectrophotometry and epr are indicative of type ii copper with typical d-d transitions. re-oxidation of fully reduced czce led to ... | 2008 | 18029263 |
| cytomics reaches microbiology-population heterogeneity on the protein level caused by chemical stress. | 2008 | 18061956 | |
| modeling synchronous growth of bacterial populations in phased cultivation. | the phasing technique is a method for synchronizing cell populations in a bioreactor. periodic changes of substrate supply and depletion can provoke a cell cycle phasing of originally stochastic scattered proliferation patterns. synchronized cell populations characterized by changes in dna content distribution can be monitored by flow cytometry. thus, studies of the dynamics of single cells in specific cell cycle phases are facilitated. here we present an age structured model framework investiga ... | 2008 | 18084780 |
| in vivo production of scfv-displaying biopolymer beads using a self-assembly-promoting fusion partner. | recombinant production and, in particular, immobilization of antibody fragments onto carrier materials are of high interest with regard to diagnostic and therapeutic applications. in this study, the recombinant production of scfv-displaying biopolymer beads intracellularly in escherichia coli was investigated. an anti-beta-galactosidase scfv (single chain variable fragment of an antibody) was c-terminally tagged with the polymer-synthesizing enzyme phac from cupriavidus necator by generating the ... | 2008 | 18088086 |
| poly(3-hydroxybutyrate) (phb) depolymerase phaza1 is involved in mobilization of accumulated phb in ralstonia eutropha h16. | the recently finished genome sequence of ralstonia eutropha h16 harbors nine genes that are thought to encode functions for intracellular depolymerization (mobilization) of storage poly(3-hydroxybutyrate) (phb). based on amino acid similarities, the gene products belong to four classes (phaza1 to phaza5, phazb, phazc, and phazd1/phazd2). however, convincing direct evidence for the in vivo roles of the gene products is poor. in this study, we selected four candidate genes (phaza1, phazb, phazc, a ... | 2008 | 18156336 |
| functions of flavin reductase and quinone reductase in 2,4,6-trichlorophenol degradation by cupriavidus necator jmp134. | the tcprxabcyd operon of cupriavidus necator jmp134 is involved in the degradation of 2,4,6-trichlorophenol (2,4,6-tcp), a toxic pollutant. tcpa is a reduced flavin adenine dinucleotide (fadh2)-dependent monooxygenase that converts 2,4,6-tcp to 6-chlorohydroxyquinone. it has been implied via genetic analysis that tcpx acts as an fad reductase to supply tcpa with fadh2, whereas the function of tcpb in 2,4,6-tcp degradation is still unclear. in order to provide direct biochemical evidence for the ... | 2008 | 18165297 |
| degradation of ambient carbonyl sulfide by mycobacterium spp. in soil. | the ability to degrade carbonyl sulfide (cos) was confirmed in seven bacterial strains that were isolated from soil, without the addition of cos. comparative 16s rrna gene sequence analysis indicated that these isolates belonged to the genera mycobacterium, williamsia and cupriavidus. for example, mycobacterium sp. strain thi401, grown on pyg agar medium, was able to degrade an initial level of 30 parts per million by volume cos within 1 h, while 60 % of the initial cos was decreased by abiotic ... | 2008 | 18174143 |
| bacterial sulfite dehydrogenases in organotrophic metabolism: separation and identification in cupriavidus necator h16 and in delftia acidovorans sph-1. | the utilization of organosulfonates as carbon sources by aerobic or nitrate-reducing bacteria usually involves a measurable, uncharacterized sulfite dehydrogenase. this is tacitly assumed to be sulfite : ferricytochrome-c oxidoreductase [ec 1.8.2.1], despite negligible interaction with (eukaryotic) cytochrome c: the enzyme is assayed at high specific activity with ferricyanide as electron acceptor. purified periplasmic sulfite dehydrogenases (sorab, soxcd) are known from chemoautotrophic growth ... | 2008 | 18174144 |
| production of poly(3-hydroxybutyrate) from waste potato starch. | there has been a considerable interest in using low cost carbon substrates for the production of poly(3-hydroxybutyrate) (phb). we have shown that saccharified waste potato starch can be used as a viable alternative carbon source in high cell density phb production. using ralstonia eutropha ncimb 11599 with phosphate limitation, 179 g/l biomass, 94 g/l phb, y(biomass/starch) = 0.46 g/g, y(phb/starch) = 0.22 g/g, and phb productivity = 1.47 g/(l*h) were achieved. residual maltose accumulated in t ... | 2008 | 18175895 |
| transcription dynamics of the functional tfda gene during mcpa herbicide degradation by cupriavidus necator aeo106 (pro101) in agricultural soil. | a modified protocol for simultaneous extraction of rna and dna, followed by real-time polymerase chain reaction quantification, was used to investigate tfda gene expression during in situ degradation of the herbicide mcpa (4-chloro-2-methylphenoxy-acetic acid) in soil. tfda encodes an alpha-ketoglutarate-dependent dioxygenase catalysing the first step in the degradation pathway of mcpa and 2,4-d (2,4-dichlorophenoxy-acetic acid). a linear recovery of tfda mrna over three orders of magnitude was ... | 2008 | 18190516 |
| binding of the major phasin, phap1, from ralstonia eutropha h16 to poly(3-hydroxybutyrate) granules. | the surface of polyhydroxybutyrate (phb) storage granules in bacteria is covered mainly by proteins referred to as phasins. the layer of phasins stabilizes the granules and prevents coalescence of separated granules in the cytoplasm and nonspecific binding of other proteins to the hydrophobic surfaces of the granules. phasin phap1(reu) is the major surface protein of phb granules in ralstonia eutropha h16 and occurs along with three homologues (phap2, phap3, and phap4) that have the capacity to ... | 2008 | 18223073 |
| structural studies on flavohemoglobins. | the key three-dimensional features of flavohemoglobins have been unveiled by x-ray crystallographic investigations carried out on the alcaligenes eutrophus and escherichia coli proteins. flavohemoglobins are made of a globin domain fused with a ferredoxin reductase-like fad binding module and display highly conserved sequences in the active sites of both the heme-binding domain and the flavin-binding domain. structural studies are discussed and methodological approaches to the solution of the cr ... | 2008 | 18237633 |
| expression, purification, and crystallization and preliminary x-ray crystallographic analysis of cnrx from cupriavidus metallidurans ch34. | the nickel and cobalt resistance of cupriavidus metallidurans ch34 is mediated by the cnrcba efflux pump encoded by the cnryhxcbat metal resistance determinant. the products of the three genes cnryxh transcriptionally regulate expression of cnr. cnry and cnrx are membranebound proteins, probably functioning as anti-sigma factors, whereas cnrh is a cnr-specific extracytoplasmic functions (ecf) sigma factor. the periplasmic domain of cnrx (residues 29- 148) was cloned as a n-terminal his-tagged pr ... | 2008 | 18239414 |
| monitoring poly(3-hydroxybutyrate) production in cupriavidus necator dsm 428 (h16) with raman spectroscopy. | this study explored the potential of raman spectroscopy for the analysis of poly(3-hydroxybutyrate) (phb) in bacteria. phb can be formed in large amounts by certain bacteria as a storage material and is of high importance for industrial biodegradable plastic production. raman spectra were collected from cupriavidus necator dsm 428 (h16), from its non-phb-producing mutant strain c. necator dsm 541, and from pure phb, in order to determine at which raman shifts a contribution of phb in bacterial s ... | 2008 | 18266340 |
| comparative phylogenies of burkholderia, ralstonia, comamonas, brevundimonas and related organisms derived from rpob, gyrb and rrs gene sequences. | phylogenetic analysis of strains from burkholderia, ralstonia, cupriavidus, comamonas, delftia, acidovorax, brevundimonas, herbaspirillum huttiense and "pseudomonas butanovora" was performed based on the protein-coding genes rpob and gyrb and on the 16s rrna-coding gene rrs. overall, the phylogenies deduced from the three genes were concordant among themselves and with current taxonomy. however, a few differences among individual gene phylogenies were noted. for example, the separation of cupria ... | 2008 | 18280706 |
| [biosynthesis of multicomponent polyhydroxyalkanoates by wautersia eutropha]. | the effect of carbon supply on polyhydroxyalkanoate (pha) synthesis by bacteria wautersia eutropha was studied. synthesis of multicomponent pha composed of short- and long-chain monomers (c4-c8) by two natural strains (h16 and b5786) under mixotrophic conditions (co2 + alkane acids as cosubstrates) was demonstrated for the first time. the pha composition was shown to be dependent on the cosubstrate type. in the presence of odd fatty acids, four- and five-component polymers were synthesized; hydr ... | 2007 | 18297870 |
| [fatty acid composition of wautersia eutropha lipids under conditions of active polyhydroxyalkanoates synthesis]. | the fatty acid composition of the lipids of a wautersia eutropha polyhydroxyalkanoate-producing strain was studied by chromato-mass spectrometry. a total of 27 fatty acids were identified; their distribution in the cell fractions was determined. in the cytoplasmic membrane, palmitic, palmitoleic, and cis-vaccenic acids were the major components. long-chain beta-hydroxy acids and myristic acid (components of the lipopolysaccharides of the cell envelope) predominated in the fraction of strongly bo ... | 2007 | 18069320 |
| combination of n149s and d171g mutations in aeromonas caviae polyhydroxyalkanoate synthase and impact on polyhydroxyalkanoate biosynthesis. | aeromonas caviae polyhydroxyalkanoate synthase (phac(ac)) is an important biocatalyst for the synthesis of practically useful two-component polyhydroxyalkanoate copolymer, poly[(r)-3-hydroxybutyrate-co-(r)-3-hydroxyhexanoate] [p(3hb-co-3hhx)]. in a previous study, two phac(ac) mutants that have a single amino acid substitution of either asparagine 149 by serine (n149s) or aspartate 171 by glycine (d171g) were isolated as higher active enzymes by means of evolutionary engineering. in this study, ... | 2007 | 18031343 |
| the geomicrobiology of gold. | microorganisms capable of actively solubilizing and precipitating gold appear to play a larger role in the biogeochemical cycling of gold than previously believed. recent research suggests that bacteria and archaea are involved in every step of the biogeochemical cycle of gold, from the formation of primary mineralization in hydrothermal and deep subsurface systems to its solubilization, dispersion and re-concentration as secondary gold under surface conditions. enzymatically catalysed precipita ... | 2007 | 18043665 |
| oxalate-degrading bacteria can protect arabidopsis thaliana and crop plants against botrytis cinerea. | botrytis cinerea and sclerotinia sclerotiorum secrete oxalic acid as a pathogenicity factor with a broad action. consequently, it should be possible to interfere with the infection process by degrading oxalic acid during the interaction of these pathogens with their hosts. we have evaluated the potential of oxalate-degrading bacteria to protect plants against pathogenic fungi. such bacteria were isolated from agricultural soil and selected on agar plates with ca-oxalate as the sole carbon source ... | 2007 | 17990961 |