| comparative evaluation of the bd phoenix and vitek 2 automated instruments for identification of isolates of the burkholderia cepacia complex. | we evaluated two new automated identification systems, the bd phoenix (becton dickinson) and the vitek 2 (biomérieux), for identification of isolates of the burkholderia cepacia complex (bcc). the test sample included 42 isolates of the highly virulent and epidemic genomovar iii, 45 isolates of b. multivorans, and 47 isolates of other members of the bcc. rates of correct identification by the bd phoenix and vitek 2 were similar when all bcc isolates were considered (50 and 53%, respectively) but ... | 2002 | 11980954 |
| identification of novel sulfur-containing bacterial polyesters: biosynthesis of poly(3-hydroxy-s-propyl-omega-thioalkanoates) containing thioether linkages in the side chains. | this study describes the biosynthesis of novel sulfur-containing polyhydroxyalkanoates (phas), which consist exclusively of hydroxypropylthioalkanoic acid containing thioether groups in the side chains. in addition, the utilization of alkylthioalkanoic acids (=thia fatty acids) by various bacteria was investigated. based on feedings with propylthiooctanoic acid (pto) or propylthiohexanoic acid, the metabolically engineered pha-negative mutant phb(-)4 of ralstonia eutropha, which harbours plasmid ... | 2002 | 11988513 |
| distribution of type iii secretion gene clusters in burkholderia pseudomallei, b. thailandensis and b. mallei. | burkholderia pseudomallei, the causative agent of melioidosis, carries a cluster of genes closely related in organisation to the type iii secretion (tts) system gene clusters of the plant pathogens ralstonia solanacearum and xanthomonas spp. the tts gene cluster (tts1) is present only in b. pseudomallei and not in avirulent b. thailandensis. adjacent to the gene cluster encoding putative secreton structural proteins lie a number of open reading frames (orfs) encoding putative proteins with littl ... | 2002 | 11990489 |
| engineering of ralstonia eutropha for production of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) from fructose and solid-state properties of the copolymer. | recombinant ralstonia eutropha capable of producing poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) copolymer [p(3hb-co-3hhx)] from fructose was engineered by introduction of genes for crotonyl-coa reductase (ccr) from streptomyces cinnamonensis (ccrsc) and for pha synthase and (r)-specific enoyl-coa hydratase from aeromonas caviae (phac-jac). in this recombinant strain, c6-acyl-coa intermediates were provided via beta-ketothiolase-mediated elongation of butyryl-coa, which was generated from croto ... | 2002 | 12005535 |
| the role of hydrogenases in the anaerobic microbiologically influenced corrosion of steels. | the direct electron transfer between 316 l stainless steel and the nad-dependent hydrogenase from ralstonia eutropha was studied by spectroelectrochemistry. the presence of hydrogenase and nad+ clearly increased the quantity of electricity, which was consumed during the electrolysis performed at potential lower than -0.70 v/sce. the involvement of hydrogenase in the cathodic depolarisation theory was discussed in the light of these results. | 2002 | 12009448 |
| the iron-containing superoxide dismutase of ralstonia metallidurans ch34. | the iron-containing superoxide dismutase (fe-sod) of ralstonia metallidurans ch34 was purified and characterised as a homodimer of 2 x 21500 da containing one iron atom per monomer and exhibiting all the characteristics of the prokaryotic fe-sods except for a higher isoelectric point. the protein was 2-fold overexpressed in the presence of selenite, zinc or paraquat. r. metallidurans ch34 was suggested to contain a gene encoding for a manganese-containing sod located in the inducible chromate re ... | 2002 | 12023089 |
| osmoregulated periplasmic glucans of the free-living photosynthetic bacterium rhodobacter sphaeroides. | the osmoregulated periplasmic glucans (opgs) produced by rhodobacter sphaeroides, a free-living organism, were isolated by trichloracetic acid treatment and gel permeation chromatography. compounds obtained were characterized by compositional analysis, matrix-assisted laser desorption ionization mass spectrometry and nuclear magnetic resonance. r. sphaeroides predominantly synthesizes a cyclic glucan containing 18 glucose residues that can be substituted by one to seven succinyl esters residues ... | 2002 | 12027884 |
| catabolic and genetic diversity of degradative bacteria from fuel-hydrocarbon contaminated aquifers. | a bstractsubsurface sediments were recovered from two aquifers contaminated with petroleum hydrocarbons in order to isolate and characterize indigenous microorganisms capable of biodegrading fuel-related compounds. these sediments had been previously studied using catabolic gene probes providing putative demonstration of significant biodegradation potential. based on 16s rdna sequence analysis, the isolates were phylogenetically similar to common soil microorganisms, including members of the gen ... | 2000 | 12035098 |
| characterization of unusual bacteria isolated from respiratory secretions of cystic fibrosis patients and description of inquilinus limosus gen. nov., sp. nov. | using a polyphasic approach (including cellular protein and fatty acid analysis, biochemical characterization, 16s ribosomal dna sequencing, and dna-dna hybridizations), we characterized 51 bacterial isolates recovered from respiratory secretions of cystic fibrosis (cf) patients. our analyses showed that 24 isolates belong to taxa that have so far not (or only rarely) been reported from cf patients. these taxa include acinetobacter sp., bordetella hinzii, burkholderia fungorum, comamonas testost ... | 2002 | 12037065 |
| opportunistic colonization of ralstonia solanacearum-infected plants by acinetobacter sp. and its natural competence development. | the behavior of the soil bacterium acinetobacter sp. bd413 was monitored in ralstonia solanacearum-infected and non-infected tomato plants after direct injection into the stem or natural infection by roots. in healthy plants, acinetobacter sp. bd413 failed to colonize plant tissue. in plants infected simultaneously by the pathogen r. solanacearum,the acinetobacter population increased linearly to about 3.1 x 10(7) cells per gram plant material and was maintained at a high level until the death o ... | 2002 | 12037607 |
| in vitro evolution of a polyhydroxybutyrate synthase by intragenic suppression-type mutagenesis. | in vitro evolution was applied to obtain highly active mutants of ralstonia eutropha polyester synthase (phbc(re)), which is a key enzyme catalyzing the formation of polyhydroxybutyrate (phb) from (r)-3-hydroxybutyryl-coa (3hb-coa). to search for beneficial mutations for activity improvement of this enzyme, we have conducted multi-step mutations, including activity loss and intragenic suppression-type activity reversion. among 259 revertants, triple mutant e11s12 was obtained as the most active ... | 2002 | 12038975 |
| genetic dissection of ralstonia solanacearum hrp gene cluster reveals that the hrpv and hrpx proteins are required for hrp pilus assembly. | in both plant and mammalian gram-negative pathogenic bacteria, type iii secretion systems (ttsss) play a crucial role in interactions with the host. all these systems share conserved proteins (called hrc in plant pathogens), but each bacterium also produces a variable number of additional type iii proteins either unique or with counterparts only in a limited number of related systems. in order to investigate the role of the different proteins encoded by the hrp gene cluster of the phytopathogeni ... | 2002 | 12046592 |
| genetic and biochemical characterization of a 2,4,6-trichlorophenol degradation pathway in ralstonia eutropha jmp134. | ralstonia eutropha jmp134 can grow on several chlorinated aromatic pollutants, including 2,4-dichlorophenoxyacetate and 2,4,6-trichlorophenol (2,4,6-tcp). although a 2,4,6-tcp degradation pathway in jmp134 has been proposed, the enzymes and genes responsible for 2,4,6-tcp degradation have not been characterized. in this study, we found that 2,4,6-tcp degradation by jmp134 was inducible by 2,4,6-tcp and subject to catabolic repression by glutamate. we detected 2,4,6-tcp-degrading activities in jm ... | 2002 | 12057943 |
| substrate specificity of nickel/cobalt permeases: insights from mutants altered in transmembrane domains i and ii. | hoxn, a high-affinity, nickel-specific permease of ralstonia eutropha h16, and nhlf, a nickel/cobalt permease of rhodococcus rhodochrous j1, are structurally related members of the nickel/cobalt transporter (nicot) family. these transporters have an eight-helix structure and are characterized by highly conserved segments with polar or charged amino acid residues in transmembrane domains (tmds) ii, iii, v, and vi. two histidine residues in a ni2+ binding motif, the signature sequence of nicots, i ... | 2002 | 12057951 |
| activation of the pseudomonas aeruginosa type iii secretion system requires an intact pyruvate dehydrogenase aceab operon. | pseudomonas aeruginosa clinical cystic fibrosis isolate cha was mutagenized with tn5tc to identify new genes involved in type iii secretion system (ttss)-dependent cytotoxicity toward human polymorphonuclear neutrophils. among 25 mutants affected in ttss function, 14 contained the insertion at different positions in the aceab operon encoding the pdh-e1 and -e2 subunits of pyruvate dehydrogenase. in pdh mutants, no transcriptional activation of ttss genes in response to calcium depletion occurred ... | 2002 | 12065547 |
| tfdd(ii), one of the two chloromuconate cycloisomerases of ralstonia eutropha jmp134 (pjp4), cannot efficiently convert 2-chloro- cis, cis-muconate to trans-dienelactone to allow growth on 3-chlorobenzoate. | ralstonia eutropha jmp134 (pjp4) harbors two functional gene clusters for the degradation of chlorocatechols, i.e. tfdcdef (in short: tfd (i)) and tfdd (ii) c (ii) e (ii) f (ii) (in short: tfd (ii)), which are both present on the catabolic plasmid pjp4. in this study, we compared the function of both gene clusters for degradation of chlorocatechols by constructing isolated and hybrid tfd (i)- tfd (ii) clusters on plasmids in r. eutropha, by activity assays of tfd enzymes, and by hplc/ms of indiv ... | 2002 | 12070765 |
| heterotrophic bacteria growing in association with methylococcus capsulatus (bath) in a single cell protein production process. | the methanotrophic bacterium methylococcus capsulatus (bath) grows on pure methane. however, in a single cell protein production process using natural gas as methane source, a bacterial consortium is necessary to support growth over longer periods in continuous cultures. in different bioreactors of norferm danmark a/s, three bacteria consistently invaded m. capsulatus cultures growing under semi-sterile conditions in continuous culture. these bacteria have now been identified as a not yet descri ... | 2002 | 12073128 |
| the copy number of the catabolic plasmid pjp4 affects growth of ralstonia eutropha jmp134 (pjp4) on 3-chlorobenzoate. | ralstonia eutropha jmp134 (pjp4) grows on 3-chlorobenzoate (3-cb) or 2,4-dichlorophenoxyacetate (2,4-d). the copy number of chlorocatechol genes has been observed to be important for allowing growth of bacterial strains on chloroaromatic compounds. despite the fact that two functional chlorocatechol degradation tfd gene clusters are harbored on plasmid pjp4, a single copy of the region comprising all tfd genes in strain jmp134-f was insufficient to allow growth on 3-cb, whereas growth on 2,4-d w ... | 2002 | 12076793 |
| in situ transfer of antibiotic resistance genes from transgenic (transplastomic) tobacco plants to bacteria. | interkingdom gene transfer is limited by a combination of physical, biological, and genetic barriers. the results of greenhouse experiments involving transplastomic plants (genetically engineered chloroplast genomes) cocolonized by pathogenic and opportunistic soil bacteria demonstrated that these barriers could be eliminated. the acinetobacter sp. strain bd413, which is outfitted with homologous sequences to chloroplastic genes, coinfected a transplastomic tobacco plant with ralstonia solanacea ... | 2002 | 12089013 |
| enrichment double-antibody sandwich indirect enzyme-linked immunosorbent assay that uses a specific monoclonal antibody for sensitive detection of ralstonia solanacearum in asymptomatic potato tubers. | sensitive and specific routine detection of ralstonia solanacearum in symptomless potato tubers was achieved by efficient enrichment followed by a reliable double-antibody sandwich indirect enzyme-linked immunosorbent assay based on the specific monoclonal antibody 8b-ivia. this monoclonal antibody reacted with 168 typical r. solanacearum strains and did not recognize 174 other pathogenic or unidentified bacteria isolated from potato. the optimized protocol included an initial enrichment step co ... | 2002 | 12089053 |
| ralstonia pickettii traced in blood culture bottles. | over a 9-month period, 14 strains of ralstonia pickettii were isolated from various biological samples inoculated in a blood culture medium. molecular epidemiological investigation confirmed the relatedness of the strains. the source of the contamination proved to be the blood culture bottle caps. | 2002 | 12089303 |
| characterization of polychlorinated biphenyl-degrading bacteria isolated from contaminated sites in czechia. | biphenyl-utilizing polychlorinated biphenyls (pcb)-degrading bacteria were isolated from sites highly contaminated by pcbs, and their degradation abilities were determined using gc for typical commercial pcb mixtures (delor 103 and delor 106). out of twelve strains which utilized biphenyl as a sole source of carbon and energy, strains pseudomonas alcaligenes kp2 and p. fluorescens kp12, characterized by the biolog identification system and the neferm test, were shown to significantly co-metaboli ... | 2002 | 12094733 |
| infection by ralstonia species in cystic fibrosis patients: identification of r. pickettii and r. mannitolilytica by polymerase chain reaction. | the frequency of respiratory tract infections caused by ralstonia species in persons with cystic fibrosis (cf) and the role of these species in cf pulmonary disease are not well documented. in part, this lack of documentation may be attributed to the difficulty in accurately identifying ralstonia species; r. mannitolilytica and r. pickettii in particular may be misidentified as other closely related species, particularly those of the burkholderia cepacia complex. we used polyphasic analyses to i ... | 2002 | 12095436 |
| enzymatic hydrolysis of bacterial poly(3-hydroxybutyrate-co-3-hydroxypropionate)s by poly(3-hydroxyalkanoate) depolymerase from acidovorax sp. tp4. | enzymatic degradability has been investigated for a series of bacterial poly(3-hydroxybutyrate-co-3-hydroxypropionate)s (p(3hb-co-3hp)s) with 3-hydroxypropionate (3hp) unit contents from 11 to 86 mol % as well as poly(3-hydroxybutyrate) (p(3hb)) and chemosynthesized poly(3-hydroxypropionate) (p(3hp)). the behavior of degradation by two types of extracellular poly(3-hydroxyalkanoate) (pha) depolymerases purified from ralstonia pikettii t1 and acidovorax sp. tp4, defined respectively as pha depoly ... | 2002 | 12099829 |
| importance of different tfd genes for degradation of chloroaromatics by ralstonia eutropha jmp134. | the tfdc(i)d(i)e(i)f(i,) and tfdd(ii)c(ii)e(ii)f(ii) gene modules of plasmid pjp4 of ralstonia eutropha jmp134 encode complete sets of functional enzymes for the transformation of chlorocatechols into 3-oxoadipate, which are all expressed during growth on 2,4-dichlorophenoxyacetate (2,4-d). however, activity of tfd(i)-encoded enzymes was usually higher than that of tfd(ii)-encoded enzymes, both in the wild-type strain grown on 2,4-d and in 3-chlorobenzoate-grown derivatives harboring only one tf ... | 2002 | 12107121 |
| method for qualifying microbial removal performance of 0.1 micron rated filters. part iv: retention of hydrogenophaga pseudoflava (atcc 700892) and ralstonia pickettii (atcc 700591) by 0.2 and 0.22 micron rated filters. | ralstonia pickettii has emerged as a bioburden microorganism of considerable importance in pharmaceutical processes utilizing conventional 0.2 or 0.22 micron rated "sterilizing grade" filters. in this article, we re-evaluated and studied the retention efficiencies of 0.2 micron rated nylon 6.6 and 0.22 microns rated modified polyvinylidene fluoride (pvdf) filters for hydrogenophaga pseudoflava (atcc 700892) and r. pickettii (atcc 700591). out of a total of forty-four 0.2/0.22 micron rated filter ... | 2002 | 12109335 |
| the malate dehydrogenase of ralstonia eutropha and functionality of the c(3)/c(4) metabolism in a tn5-induced mdh mutant. | the tn5-induced mutant vg12 of ralstonia eutropha hf39, which was isolated in this study, revealed an interesting phenotype: it grew on fructose and pyruvate as well as autotrophically like the wild-type, whereas growth on tricarboxylic acid intermediates and glyoxylic acid was reduced, and no growth occurred if acetate, propionate or levulinate were provided as carbon source. tn5 was mapped in a gene encoding an nad(h)-dependent malate dehydrogenase (mdh), and mdh activity was strongly diminish ... | 2002 | 12113928 |
| genetics and control of co(2) assimilation in the chemoautotroph ralstonia eutropha. | the nutritional versatility of facultative autotrophs requires efficient overall control of their metabolism. most of these organisms are proteobacteria that assimilate co(2) via the highly energy-demanding calvin-benson-bassham reductive pentose-phosphate cycle. the enzymes of the cycle are encoded by cbb genes organized in cbb operons differing in size and composition, although conserved features are apparent. transcription of the operons, which may form regulons, is strictly controlled, being ... | 2002 | 12115053 |
| biochemical and enzymological properties of the polyhydroxybutyrate synthase from the extremely halophilic archaeon strain 56. | some members of the archaebacterial family halobacteriaceae have been determined to accumulate polyhydroxyalkanoate (pha) and poly(3-hydroxybutyrate) (phb). the extremely halophilic archaebacterium strain 56 is capable of accumulating large amounts of phb. since measurements of enzyme activities related to archaebacterial phb biosynthesis have never been achieved, we investigated the enzymology of phb biosynthesis in strain 56. crude extracts of strain 56 cultivated under accumulating conditions ... | 2002 | 12139978 |
| molecular breeding of transgenic rice plants expressing a bacterial chlorocatechol dioxygenase gene. | the cbna gene encoding the chlorocatechol dioxygenase gene from ralstonia eutropha nh9 was introduced into rice plants. the cbna gene was expressed in transgenic rice plants under the control of a modified cauliflower mosaic virus 35s promoter. western blot analysis using anti-cbna protein indicated that the cbna gene was expressed in leaf tissue, roots, culms, and seeds. transgenic rice calluses expressing the cbna gene converted 3-chlorocatechol to 2-chloromucote efficiently. growth and morpho ... | 2002 | 12147507 |
| comparative genomic analysis of plant-associated bacteria. | this review deals with a comparative analysis of seven genome sequences from plant-associated bacteria. these are the genomes of agrobacterium tumefaciens, mesorhizobium loti, sinorhizobium meliloti, xanthomonas campestris pv campestris, xanthomonas axonopodis pv citri, xylella fastidiosa, and ralstonia solanacearum. genome structure and the metabolism pathways available highlight the compromise between the genome size and lifestyle. despite the recognized importance of the type iii secretion sy ... | 2002 | 12147758 |
| production, properties and specificity of a new bacterial l-fucose- and d-arabinose-binding lectin of the plant aggressive pathogen ralstonia solanacearum, and its comparison to related plant and microbial lectins. | the worldwide distributed plant aggressive pathogen ralstonia solanacearum, which causes lethal wilt in many agricultural crops, produces a potent l-fucose-binding lectin (rsl) exhibiting sugar specificity similar to that of pa-iil of the human aggressive opportunistic pathogen pseudomonas aeruginosa. both lectins show l-fucose > l-galactose > d-arabinose > d-mannose specificity, but the affinities of rsl to these sugars are substantially lower. unlike ulex europaeus anti-h lectin, but like pa-i ... | 2002 | 12153735 |
| survival and nutritional requirements of three bacteria isolated from ultrapure water. | bacteria isolated previously from ultrapure water (upw) systems were examined for their ability to survive in upw, with the ultimate goal of elucidating potential carbon and energy sources for the bacteria. two strains of ralstonia pickettii isolated from different areas within the upw system (pretreatment and polishing loop, and referred to as strains 3a1 and mf254a, respectively) and a strain of bradyrhizobium sp. were compared to increase our understanding of the fundamental behavior of bacte ... | 2002 | 12161774 |
| characterization of bacterial consortia capable of degrading 4-chlorobenzoate and 4-bromobenzoate under denitrifying conditions. | 4-chlorobenzoate and 4-bromobenzoate were readily degraded in denitrifying enrichment cultures established with river sediment, estuarine sediment or agricultural soil as inoculum. stable denitrifying consortia were obtained and maintained by serial dilution and repeated feeding of substrates. microbial community analyses were performed to characterize the 4-chlorobenzoate and 4-bromobenzoate degrading consortia with terminal restriction fragment length polymorphism (t-rflp) and cloning of 16s r ... | 2002 | 12167535 |
| regulation of phasin expression and polyhydroxyalkanoate (pha) granule formation in ralstonia eutropha h16. | regulation of expression of the phasin phap, which is the major protein at the surface of polyhydroxyalkanoate (pha) granules in ralstonia eutropha h16, was studied and analysed at the molecular level. the regulation of phap expression is achieved by an autoregulated repressor, which is encoded by phar in r. eutropha. the occurrence of phar homologues and the organization of phar genes was analysed in detail in 29 different bacteria. three kinds of molecule to which phar binds were identified in ... | 2002 | 12177335 |
| characterization of copolymer hydroxybutyrate/hydroxyvalerate from saponified vernonia, soybean, and "spent" frying oils. | poly(beta-hydroxyalkanoate)s (phas) were biosynthesized by ralstonia eutropha (formerly known as alcaligenes eutrophus) by using saponified soybean, vernonia, and "spent" frying oils. these phas were isolated and characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (maldi-tofms), gas chromatography/mass spectrometry (gc/ms), proton nuclear magnetic resonance spectrometry (1h nmr), and 2-dimensional homonuclear (1h-1h) correlation spectroscopy (cosy). the ... | 2002 | 12180688 |
| identification of bacteria in drinking and purified water during the monitoring of a typical water purification system. | a typical purification system that provides purified water which meets ionic and organic chemical standards, must be protected from microbial proliferation to minimize cross-contamination for use in cleaning and preparations in pharmaceutical industries and in health environments. | 2002 | 12182763 |
| characterization of four olive-mill-wastewater indigenous bacterial strains capable of aerobically degrading hydroxylated and methoxylated monocyclic aromatic compounds. | seven aerobic bacterial strains capable of degrading several of the monocyclic aromatic compounds occurring in the phenolic fraction of olive-mill wastewaters (omws) were isolated from an italian omw. the results of the 16s rdna restriction analysis evidenced that these strains are distributed among four different groups. one strain of each group was taxonomically characterized by sequencing the amplified 16s rdna, and the four strains were assigned to the genera comamonas (strain av1a), ralston ... | 2002 | 12189422 |
| [the study of bacterial glycopolymers using laser spectroscopy]. | a possibility has been demonstrated to use laser spectroscopy of bacterial glycopolymers by means of measurement of their water solutions fluorescence. comparative investigations of native lipopolysaccharide (lps) ralstonia solanacearum and its structure components permits a supposition to be made that the lps total spectrum is a result of superposition of the spectrum of o-specific polysaccharide and core oligosaccharide as well as core oligosaccharide and lipid a. the lps spectrum maximum shif ... | 2002 | 12190019 |
| carbonic anhydrase is essential for growth of ralstonia eutropha at ambient co(2) concentrations. | mutant strain 25-1 of the facultative chemoautotroph ralstonia eutropha h16 had previously been shown to exhibit an obligately high-co(2)-requiring (hcr) phenotype. although the requirement varied with the carbon and energy sources utilized, none of these conditions allowed growth at the air concentration of co(2). in the present study, a gene designated can and encoding a beta-carbonic anhydrase (ca) was identified as the site altered in strain 25-1. the mutation caused a replacement of the hig ... | 2002 | 12193617 |
| biotransformation of eugenol to ferulic acid by a recombinant strain of ralstonia eutropha h16. | the gene loci ehyab, cala, and calb, encoding eugenol hydroxylase, coniferyl alcohol dehydrogenase, and coniferyl aldehyde dehydrogenase, respectively, which are involved in the first steps of eugenol catabolism in pseudomonas sp. strain hr199, were amplified by pcr and combined to construct a catabolic gene cassette. this gene cassette was cloned in the newly designed broad-host-range vector pbbr1-jo2 (pbbr1-jo2ehyabcalacalb) and transferred to ralstonia eutropha h16. a recombinant strain of r. ... | 2002 | 12200281 |
| the h(2) sensor of ralstonia eutropha: biochemical and spectroscopic analysis of mutant proteins modified at a conserved glutamine residue close to the [nife] active site. | [nife] hydrogenases contain a highly conserved histidine residue close to the [nife] active site which is altered by a glutamine residue in the h(2)-sensing [nife] hydrogenases. in this study, we exchanged the respective glutamine residue of the h(2) sensor (rh) of ralstonia eutropha, q67 of the rh large subunit hoxc, by histidine, asparagine and glutamate. the replacement by histidine and asparagine resulted in slightly unstable rh proteins which were hardly affected in their regulatory and enz ... | 2002 | 12203028 |
| enzymatic hydrolysis of chemosynthesized atactic poly(3-hydroxybutyrate) by poly(3-hydroxyalkanoate) depolymerase from acidovorax sp. tp4 and ralstonia pickettii t1. | the enzymatic degradability of chemosynthesized atactic poly([r,s]-3-hydroxybutyrate) [a-p(3hb)] by two types of extracellular poly(3-hydroxyalkanoate) (pha) depolymerases purified from ralstonia pickettii t1 (phaz(ral)) and acidovorax sp. tp4 (phaz(aci)), defined respectively as pha depolymerase types i and ii according to the position of the lipase box in the catalytic domain, were studied. the enzymatic degradation of a-p(3hb) by phaz(aci) depolymerase was confirmed from the results of weight ... | 2002 | 12217032 |
| metabolism of dichloromethylcatechols as central intermediates in the degradation of dichlorotoluenes by ralstonia sp. strain ps12. | ralstonia sp. strain ps12 is able to use 2,4-, 2,5-, and 3,4-dichlorotoluene as growth substrates. dichloromethylcatechols are central intermediates that are formed by teca tetrachlorobenzene dioxygenase-mediated activation at two adjacent unsubstituted carbon atoms followed by tecb chlorobenzene dihydrodiol dehydrogenase-catalyzed rearomatization and then are channeled into a chlorocatechol ortho cleavage pathway involving a chlorocatechol 1,2-dioxygenase, chloromuconate cycloisomerase, and die ... | 2002 | 12218011 |
| formation of protoanemonin from 2-chloro-cis,cis-muconate by the combined action of muconate cycloisomerase and muconolactone isomerase. | muconate cycloisomerases are known to catalyze the reversible conversion of 2-chloro-cis,cis-muconate by 1,4- and 3,6-cycloisomerization into (4s)-(+)-2-chloro- and (4r/5s)-(+)-5-chloromuconolactone. 2-chloromuconolactone is transformed by muconolactone isomerase with concomitant dechlorination and decarboxylation into the antibiotic protoanemonin. the low k(cat) for this compound compared to that for 5-chloromuconolactone suggests that protoanemonin formation is of minor importance. however, si ... | 2002 | 12218027 |
| evaluation of procedures for reliable pcr detection of ralstonia solanacearum in common natural substrates. | several procedures were compared for reliable pcr detection of ralstonia solanacearum in common substrates (plant, seed, water and soil). in order to prevent the inhibition of pcr by substances contained in crude extracts, numerous dna extraction procedures as well as additives to buffers or pcr mixtures were checked. our results showed that the efficiency of these methods or compounds depended greatly upon the nature of the sample. consequently, preparation of samples prior to pcr depended upon ... | 2002 | 12223295 |
| amplification of rna by nasba allows direct detection of viable cells of ralstonia solanacearum in potato. | the objective of this study was to develop a nucleic acid sequence based amplification (nasba) assay, targeting 16s rrna sequences, for direct detection of viable cells of ralstonia solanacearum, the causal organism of bacterial wilt. the presence of intact 16s rrna is considered to be a useful indicator for viability, as a rapid degradation of this target molecule is found upon cell death. | 2002 | 12234348 |
| an arsenic(iii)-oxidizing bacterial population: selection, characterization, and performance in reactors. | to select an autotrophic arsenic(iii)-oxidizing population, named caso1, and to evaluate the performance of the selected bacteria in reactors. | 2002 | 12234349 |
| heca, a member of a class of adhesins produced by diverse pathogenic bacteria, contributes to the attachment, aggregation, epidermal cell killing, and virulence phenotypes of erwinia chrysanthemi ec16 on nicotiana clevelandii seedlings. | erwinia chrysanthemi is representative of a broad class of bacterial pathogens that are capable of inducing necrosis in plants. the e. chrysanthemi ec16 heca gene predicts a 3,850-aa member of the bordetella pertussis filamentous hemagglutinin family of adhesins. a hecatn7 mutant was reduced in virulence on nicotiana clevelandii seedlings after inoculation without wounding. epifluorescence and confocal laser-scanning microscopy observations of heca and wild-type cells expressing the green fluore ... | 2002 | 12271135 |
| microbial origin of glutamate, hibernation and tissue trauma: an in vivo microdialysis study. | using quantitative microdialysis in hibernating arctic ground squirrels (ags), striatal glutamate concentrations ([glu](dia)) progressively increased to approximately 200 microm after 3 days of microdialysis in euthermic but not hibernating ground squirrels. initially, the progressive increase in [glu](dia) was thought to be related to greater tissue response in euthermic animals. alternatively, given the vastly different body temperatures between the two groups (37 vs. 3 degrees c), glutamate m ... | 2002 | 12323415 |
| carbon and hydrogen stable isotope fractionation during aerobic bacterial degradation of aromatic hydrocarbons. | 13c/(12)c and d/h stable isotope fractionation during aerobic degradation was determined for pseudomonas putida strain mt-2, pseudomonas putida strain f1, ralstonia pickettii strain pko1, and pseudomonas putida strain ncib 9816 grown with toluene, xylenes, and naphthalene. different types of initial reactions used by the respective bacterial strains could be linked with certain extents of stable isotope fractionation during substrate degradation. | 2002 | 12324375 |
| use of 16s rrna gene sequencing for identification of nonfermenting gram-negative bacilli recovered from patients attending a single cystic fibrosis center. | during 1999, we used partial 16s rrna gene sequencing for the prospective identification of atypical nonfermenting gram-negative bacilli isolated from patients attending our cystic fibrosis center. of 1,093 isolates of nonfermenting gram-negative bacilli recovered from 148 patients, 46 (4.2%) gave problematic results with conventional phenotypic tests. these 46 isolates were genotypically identified as pseudomonas aeruginosa (19 isolates, 12 patients), achromobacter xylosoxidans (10 isolates, 8 ... | 2002 | 12354883 |
| cloning of the class d beta-lactamase gene from burkholderia pseudomallei and studies on its expression in ceftazidime-susceptible and -resistant strains. | ceftazidime is the antibiotic of choice for the treatment of melioidosis. ceftazidime-resistant burkholderia pseudomallei have been identified and beta-lactamase production implicated in resistance. in this study, 25 strains of b. pseudomallei (15 clinical and 10 environmental strains) were examined for their ability to yield mutants that overexpress beta-lactamase. ceftazidime-resistant mutants were selected readily at high frequency and displayed four- to eight-fold increases in the mics of ce ... | 2002 | 12356787 |
| functional analysis by site-directed mutagenesis of the nad(+)-reducing hydrogenase from ralstonia eutropha. | the tetrameric cytoplasmic [nife] hydrogenase (sh) of ralstonia eutropha couples the oxidation of hydrogen to the reduction of nad(+) under aerobic conditions. in the catalytic subunit hoxh, all six conserved motifs surrounding the [nife] site are present. five of these motifs were altered by site-directed mutagenesis in order to dissect the molecular mechanism of hydrogen activation. based on phenotypic characterizations, 27 mutants were grouped into four different classes. mutants of the major ... | 2002 | 12399498 |
| ralstonia solanacearum requires type 4 pili to adhere to multiple surfaces and for natural transformation and virulence. | as reported previously for ralstonia solanacearum strain gmi1000, wild-type strains aw1 and k60 were shown to produce hrp pili. aw1 and k60 mutants lacking hrp pili still exhibited twitching motility, which requires type 4 pili (tfp), and electron microscopy revealed that they still made flexuous polar pili. twitching-positive cells had an extracellular 17 kda protein that was associated with piliation, and an internal 43-amino-acid sequence of this protein was typical of type 4 pilins. this ami ... | 2002 | 12406219 |
| characterization of the adaptive response to trichloroethylene-mediated stresses in ralstonia pickettii pko1. | in ralstonia pickettii pko1, a denitrifying toluene oxidizer that carries a toluene-3-monooxygenase (t3mo) pathway, the biodegradation of toluene and trichloroethylene (tce) by the organism is induced by tce at high concentrations. in this study, the effect of tce preexposure was studied in the context of bacterial protective response to tce-mediated toxicity in this organism. the results of tce degradation experiments showed that cells induced by tce at 110 mg/liter were more tolerant to tce-me ... | 2002 | 12406709 |
| a novel class of self-sufficient cytochrome p450 monooxygenases in prokaryotes. | the bacillus cytochrome p450 bm3 integrates an entire p450 system in one polypeptide and represents a convenient prokaryotic model for microsomal p450s. this self-sufficient class ii p450 is also present in actinomycetes and fungi. by genome analysis we have identified additional homologues in the pathogenic species bacillus anthracis and bacillus cereus, and in ralstonia metallidurans. this analysis also revealed a novel class of putative self-sufficient p450s, p450 pfor, comprising a class i p ... | 2002 | 12419614 |
| diversity of transconjugants that acquired plasmid pjp4 or pemt1 after inoculation of a donor strain in the a- and b-horizon of an agricultural soil and description of burkholderia hospita sp. nov. and burkholderia terricola sp. nov. | we examined the diversity of transconjugants that acquired the catabolic plasmids pjp4 or pemt1, which encode degradation of 2,4-dichlorophenoxyacetic acid (2,4-d), in microcosms with agricultural soil inoculated with a donor strain (dejonghe, w., goris, j., el fantroussi, s., höfte, m., de vos, p., verstraete, w., and top, e. m. appl. environ. microbiol. 2000, p. 3297-3304). using repetitive element pcr fingerprinting, eight different rep-clusters and six separate isolates could be discriminate ... | 2002 | 12421072 |
| change of surface structure of poly(3-hydroxybutyrate) film upon enzymatic hydrolysis by phb depolymerase. | the change in the surface structure of poly[(r)-3-hydroxybutyrate] [phb] films upon the enzymatic hydrolysis was analyzed by attenuated total reflection infrared [atr/ir] spectrometry. as enzymes, phb depolymerases isolated from ralstonia pickettii t1 and pseudomonas stutzeri were used. by curve decomposition of the carbonyl stretching band of atr/ir spectra, the change in the surface crystallinity of phb films by exposure to buffer containing 0, 1, and 4 microg of phb depolymerases was estimate ... | 2002 | 12425671 |
| novel insights into the interplay between peripheral reactions encoded by xyl genes and the chlorocatechol pathway encoded by tfd genes for the degradation of chlorobenzoates by ralstonia eutropha jmp134. | many bacteria can grow on chloroaromatic pollutants because they can transform them into chlorocatechols, which are further degraded by enzymes of a specialized ortho-cleavage pathway. ralstonia eutropha jmp134 is able to grow on 3-chlorobenzoate by using two pjp4-encoded, ortho-cleavage chlorocatechol degradation gene clusters (tfdc(i)d(i)e(i)f(i) and tfdd(ii)c(ii)e(ii)f(ii)). very little is known about the acquisition of new catabolic genes encoding enzymes that lead to the formation of chloro ... | 2002 | 12427935 |
| carbazolequinone induction of caspase-dependent cell death in src-overexpressing cells. | we previously reported that rsv-transformed quail neuroretina cells (qnr-ts68) were highly resistant to apoptosis provoked by serum withdrawal, and that this property was due to v-src kinase activity. the present study investigates the cytotoxic effect and the functional mechanism of carbazolequinone-mediated cell death in this system. qnr-ts68 cells were subjected to carbazolequinone treatment and both growth inhibition and cell death induction were examined using formazan assays. cell death me ... | 2002 | 12429350 |
| is the contribution of bacteria to terrestrial carbon budget greatly underestimated? | some commonly found species of soil bacteria use low molecular weight organic acids as their sole source of carbon and energy. this study shows that acids such as citrate and oxalate (produced in large amounts by fungi and plants) can rapidly be consumed by these bacteria. two strains, ralstonia eutropha and xanthobacter autotrophicus, were cultured on acetate- and citrate-rich media. the resulting co2 and/or hco3- reacted with calcium ions to precipitate two polymorphs of calcium carbonate (cac ... | 2002 | 12435038 |
| popp1, a new member of the yopj/avrrxv family of type iii effector proteins, acts as a host-specificity factor and modulates aggressiveness of ralstonia solanacearum. | a functional analysis of an 11-kb-long region of the genome of the plant-pathogenic bacterium ralstonia solanacearum, previously identified as an alternative codon usage region (acur), reveals that it was probably acquired through horizontal gene transfer. this acur encodes an insertion sequence and eight potential proteins, one of which is partially homologous with a host-specificity factor from a plant-pathogenic erwinia sp., and another, popp1, which is homologous to members of the yopj/avrrx ... | 2002 | 12437304 |
| chemotaxis of a ralstonia sp. sj98 toward co-metabolizable nitroaromatic compounds. | we have earlier reported chemotaxis of a gram-negative, motile ralstonia sp. sj98 towards p-nitrophenol (pnp), 4-nitrocatechol (nc), o-nitrobenzoate (onb), p-nitrobenzoate (pnb), and 3-methyl-4-nitrophenol (mnp) that also served as sole source of carbon and energy to the strain [s.k. samanta, b. bhushan, a. chauhan, r.k. jain, biochem. biophy. res. commun. 269 (2000) 117; b. bhushan, s.k. samanta, a. chauhan, a.k. chakraborti, r.k. jain, biochem. biophy. res. commun. 275 (2000) 129]. in this pap ... | 2002 | 12445815 |
| a novel high-cell-density protein expression system based on ralstonia eutropha. | we describe the development of a novel protein expression system based on the industrial fermentation organism ralstonia eutropha (formerly known as alcaligenes eutrophus) ncimb 40124. this new system overcomes some of the shortcomings of traditional escherichia coli-based protein expression systems, particularly the propensity of such systems to form inclusion bodies during high-level expression. using a proteomics approach, we identified promoters that can be induced by simple process paramete ... | 2002 | 12450812 |
| specific detection and differentiation of two subspecies of fusobacterium necrophorum by pcr. | the phylogenic relationships of two subspecies of fusobacterium necrophorum were investigated by randomly amplified polymorphism dna-polymerase chain reaction (rapd-pcr). with each of the 12 random primers, the dna fingerprints generated were subjected to cluster analysis for dendrograms. the analysis indicated that twelve strains were organized into two major clusters, and that all strains of each subspecies were confined to one cluster. furthermore, two of the random primers examined each gene ... | 2003 | 12458167 |
| new genes involved in chromate resistance in ralstonia metallidurans strain ch34. | chromate resistance in ralstonia metallidurans ch34 is based on chromate efflux catalyzed by chra efflux pumps. the bacterium harbors two chromate resistance determinants, the previously known chr(1) on plasmid pmol28 (genes chri, chrb(1), chra(1), chrc, chre, chrf(1)) and chr(2) on the chromosome (genes chrb(2), chra(2), chrf(2)). deletion of the genes chri, chrc, chra(2), chrb(2) and chrf(2) influenced chromate resistance and transcription from a chrbp(1) ::lacz fusion. deletion of the plasmid ... | 2002 | 12471500 |
| type iv pili are not specifically required for contact dependent translocation of exoenzymes by pseudomonas aeruginosa. | the type iii secretion system (ttss) of the opportunistic pathogen pseudomonas aeruginosa enables the bacterium to deliver exoenzymes directly into the eukaryotic cell. in this study we have investigated the role of key factors involved in this process. we could demonstrate that the translocators popb, popd and pcrv are absolutely required for delivery of exoenzyme s into host cells. by analyzing different tfp (type iv pili) mutants we could establish a correlation between the frequency of bacte ... | 2002 | 12495673 |
| degradation and transformability of dna from transgenic leaves. | the fate of transplastomic (chloroplast genome contains the transgene) tobacco plant dna in planta was studied when the plant leaves were subjected to decay conditions simulating those encountered naturally, including grinding, incubation with cellulase or enzymes produced by erwinia chrysanthemi, and attack by the plant pathogen ralstonia solanacearum. direct visualization of dna on agarose gels, gene extraction yield (the number of amplifiable aada sequences in extracted plant dna), and the fr ... | 2003 | 12514059 |
| green technology for conversion of food scraps to biodegradable thermoplastic polyhydroxyalkanoates. | a new technology is developed and demonstrated that couples anaerobic digestion of food scraps with production of biodegradable thermoplastics, polyhydroxyalkanoates (phas). the food wastes were digested in an anaerobic reactor producing four major organic acids. the concentrations of acetic, propionic, butyric, and lactic acids reached 5.5, 1.8, 27.4, and 32.7 g/l, respectively. the fermentative acids were transferred through membranes via molecule diffusion into an air-bubbling reactor where t ... | 2002 | 12521183 |
| the bacterium xenorhabdus nematophilus depresses nodulation reactions to infection by inhibiting eicosanoid biosynthesis in tobacco hornworms, manduca sexta. | the bacterium, xenorhabdus nematophilus, is a virulent insect pathogen. we tested the hypothesis that this bacterium impairs insect cellular immune defense reactions by inhibiting biosynthesis of eicosanoids involved in mediating cellular defense reactions. fifth instar tobacco hornworms, manduca sexta, produced melanized nodules in reaction to challenge with living and heat-killed x. nematophilus. however, the nodulation reactions were much attenuated in insects challenged with living bacteria ... | 2003 | 12529862 |
| acyl-homoserine lactone acylase from ralstonia strain xj12b represents a novel and potent class of quorum-quenching enzymes. | n-acylhomoserine lactones (ahls) are used as signal molecules by many quorum-sensing proteobacteria. diverse plant and animal pathogens use ahls to regulate infection and virulence functions. these signals are subject to biological inactivation by ahl-lactonases and ahl-acylases. previously, little was known about the molecular details underlying the latter mechanism. an ahl signal-inactivating bacterium, identified as a ralstonia sp., was isolated from a mixed-species biofilm. the signal inacti ... | 2003 | 12535081 |
| expression of bacterial poly(3-hydroxybutyrate) synthesis genes in hairy roots of sugar beet (beta vulgaris l.). | three genes from ralstonia eutropha necessary for poly(3-hydroxybutyrate) (phb) synthesis were introduced into the hairy roots of sugar beet. transformation of a vector construct harbouring the phb genes, each fused to the coding region of the pea ribulose-bisphosphate carboxylase plastid targeting sequence, resulted in 20 transgenic hairy-root clones, producing up to 55 mg high molecular phb/g dry weight, as identified by gas chromatography, gel permeation chromatography and hplc. accumulation ... | 2003 | 12536258 |
| adaptation to nickel spiking of bacterial communities in neocaledonian soils. | adaptation to nickel of bacterial communities of two extreme neocaledonian soils (an ultramafic soil and an acidic soil) was investigated by nickel spiking and compared with adaptation in a non-neocaledonian soil used as reference. soil microcosms were amended with nickel chloride (nicl2), and bacterial community structure was analysed with the ribosomal intergenic spacer analysis (risa) technique. then, bacterial populations that respond to nickel stress were identified by cloning and sequencin ... | 2003 | 12542708 |
| microbial diversity and resistance to copper in metal-contaminated lake sediment. | contamination of habitats with heavy metals has become a worldwide problem. we describe herein the analysis of lake sediment contaminated with high concentrations of copper as a consequence of mine milling disposal over a 100-year period. copper concentrations in the sediment were found to vary with depth and ranged from 200 to 5500 ppm. analysis of the microbial community with t-rflp identified a minimum of 20 operational taxonomic units (otu). t-rflp analysis along a depth profile detected as ... | 2003 | 12545313 |
| [cloning and sequencing of the gene encoding esterase esta from ralstonia eutropha ch34]. | an esterase-positive clone was isolated by screening a genomic library of ralstonia eutropha ch34 constructed in escherichia coli s17-1 with top agar containing alpha-naphtyl acetate and fast blue rr. a gne encoding esterase activity, esta was subcloned from this clone. nucleotide sequencing of esta showed that it was a 825 bp open reading frame, encoding an esterase esta, composed of 275 amino acids with a predicted molecular mass of 30,785 d. homology analysis revealed that esta exhibited sign ... | 2001 | 12552903 |
| monitoring gene expression in mixed microbial communities by using dna microarrays. | a dna microarray to monitor the expression of bacterial metabolic genes within mixed microbial communities was designed and tested. total rna was extracted from pure and mixed cultures containing the 2,4-dichlorophenoxyacetic acid (2,4-d)-degrading bacterium ralstonia eutropha jmp134, and the inducing agent 2,4-d. induction of the 2,4-d catabolic genes present in this organism was readily detected 4, 7, and 24 h after the addition of 2,4-d. this strain was diluted into a constructed mixed microb ... | 2003 | 12570994 |
| intergeneric transfer of chromosomal and conjugative plasmid genes between ralstonia solanacearum and acinetobacter sp. bd413. | conjugative transfer of a broad-host range plasmid and transformation-mediated transfer of chromosomal genes were found to occur at significant frequencies between ralstonia solanacearum and acinetobacter sp. in planta. these intergeneric gene transfers are related to the conditions provided by the infected plant, including the extensive multiplication of these two bacteria in planta and the development of a competence state in acinetobacter sp. although interkingdom dna transfer from nuclear tr ... | 2003 | 12580284 |
| identification of a novel gsp-related pathway required for secretion of the manganese-oxidizing factor of pseudomonas putida strain gb-1. | the manganese-oxidizing factor of pseudomonas putida strain gb-1 is associated with the outer membrane. one of the systems of protein transport across the outer membrane is the general secretory pathway (gsp). the gsp genes are called xcp in pseudomonas species. in a previous study, it was shown that mutation of the prepilin peptidase xcpa and of a homologue of the pseudopilin xcpt inhibited transport of the factor. in the present study, we describe the genomic region flanking the xcpt homologue ... | 2003 | 12581354 |
| evolution of a chlorobenzene degradative pathway among bacteria in a contaminated groundwater mediated by a genomic island in ralstonia. | the genetic structure of two ralstonia spp., strain js705 and strain js745, isolated from the same groundwater aquifer, was characterized with respect to the degradation capacities for toluene and chlorobenzene degradation. cosmid library construction, cloning, dna sequencing and mating experiments indicated that the genes for chlorobenzene degradation in strain js705 were a mosaic of the clc genes, previously described for pseudomonas sp. strain b13, and a 5 kb fragment identical to strain js74 ... | 2003 | 12588296 |
| efficient turnover of chlorocatechols is essential for growth of ralstonia eutropha jmp134(pjp4) in 3-chlorobenzoic acid. | ralstonia eutropha jmp134(pjp4) degrades 3-chlorobenzoate (3-cb) by using two not completely isofunctional, pjp4-encoded chlorocatechol degradation gene clusters, tfdc(i)d(i)e(i)f(i) and tfdd(ii)c(ii)e(ii)f(ii). introduction of several copies of each gene cluster into r. eutropha jmp222, which lacks pjp4 and thus accumulates chlorocatechols from 3-cb, allows the derivatives to grow in this substrate. however, jmp222 derivatives containing one chromosomal copy of each cluster did not grow in 3-cb ... | 2003 | 12591870 |
| identification of mixed bacterial dna contamination in broad-range pcr amplification of 16s rdna v1 and v3 variable regions by pyrosequencing of cloned amplicons. | using a sensitive and rapid method combining broad-range pcr amplification of bacterial 16s rdna fragments and pyrosequencing for detection, identification and typing, we have found contaminating bacterial dna in our reagents used for pcr. identified bacteria are the water-borne bacterial genera pseudomonas, stenotrophomonas, xanthomonas, ralstonia and bacillus. our results are in concordance with recent reports of contaminated industrial water systems. in light of this conclusion, we believe th ... | 2003 | 12594028 |
| identification of dna markers of tobacco linked to bacterial wilt resistance. | bacterial wilt caused by ralstonia solanacearum is one of the most destructive soil-borne diseases in the world. breeding resistant commercial varieties of tobacco is difficult because most donor candidates' resistance is controlled by polygenes. in this paper, we demonstrate the identification of useful dna markers for bacterial wilt-resistant tobacco breeding. one hundred and seventeen markers were identified by the amplified fragment length polymorphism (aflp) method between w6, a burley vari ... | 2003 | 12596008 |
| cloning, sequencing, and overexpression in escherichia coli of a phenylserine dehydratase gene from ralstonia pickettii ps22. | the structural gene coding for phenylserine dehydratase from ralstonia pickettii ps22 was cloned into escherichia coli cells, and the nucleotide sequence was identified. the predicted amino acid sequence had high sequence similarity to biodegradative and biosynthetic threonine dehydratases from e. coli and serine dehydratase from human liver. transformed e. coli cells overproduced phenylserine dehydratase, and the recombinant enzyme was purified to homogeneity with a high yield and characterized ... | 2002 | 12596884 |
| quantitative amino acid analysis of bovine nadh:ubiquinone oxidoreductase (complex i) and related enzymes. consequences for the number of prosthetic groups. | bovine-heart nadh:ubiquinone oxidoreductase (ec 1.6.5.3; complex i) is the first and most complicated enzyme in the mitochondrial respiratory chain. biochemistry textbooks and virtually all literature on this enzyme state that it contains one fmn and at least four iron-sulfur clusters. we show here that this statement is incorrect as it is based on erroneous protein determinations. quantitative amino acid analysis of the bovine complex i, to our knowledge the first reported thus far, shows that ... | 2003 | 12615347 |
| ralstonia basilensis m91-3, a denitrifying soil bacterium capable of using s-triazines as nitrogen sources. | the purpose of this study was to characterize the phylogenetic and phenotypic traits of m91-3, a soil bacterium capable of mineralizing atrazine (2-chloro-4-n-isopropyl-6-n-ethyl-s-triazine). the isolate was identified as ralstonia basilensis based on 99.5% homology of the 16s rrna sequence and various chemotaxonomic data. the isolate used atrazine as the sole source of energy, carbon, and nitrogen. it could also use several other s-triazines as nitrogen sources. ralstonia basilensis m91-3 was c ... | 2002 | 12619822 |
| the competitiveness of pseudomonas chlororaphis carrying pjp4 is reduced in the arabidopsis thaliana rhizosphere. | the effect of the large catabolic incp plasmid pjp4 on the competitiveness of pseudomonas chlororaphis spr044 and on its derivatives spr244 (gacs deficient), spr344 (phenazine-1-carboxamide overproducer), and spr644 (phenazine-1-carboxamide deficient) in the arabidopsis thaliana rhizosphere was assessed. solitary rhizosphere colonization by the wild type, spr244, and spr644 was not affected by the plasmid. the size of the population of spr344 carrying pjp4, however, was significantly reduced com ... | 2003 | 12620876 |
| the role of cell bioaugmentation and gene bioaugmentation in the remediation of co-contaminated soils. | soils co-contaminated with metals and organics present special problems for remediation. metal contamination can delay or inhibit microbial degradation of organic pollutants such that for effective in situ biodegradation, bioaugmentation is necessary. we monitored the degradation of 2,4-dichlorophenoxyacetic acid (2,4-d) or 3-chlorobenzoate (3-cb) in two different soils with and without cadmium (cd) contamination. additionally, we evaluated the ability of bioaugmentation to enhance organic degra ... | 2002 | 12634123 |
| synthesis of ethyl ( s)-4-chloro-3-hydroxybutanoate using fabg-homologues. | this paper is a report on the successful application of bioinformatics to enzyme screening. the synthesis of ethyl ( s)-4-chloro-3-hydroxybutanoate (echb) by asymmetric reduction of ethyl 4-chloroacetoacetate (ecaa) using fabg-homologues was studied. beta-ketoacyl-acyl carrier protein reductases from both escherichia coli and bacillus subtilis, which are components of type ii fatty acid synthase, could reduce ecaa to ( s)-echb with 94-98% ee. furthermore, acetoacetyl-coa reductases (ars) from bo ... | 2003 | 12655455 |
| 'candidatus glomeribacter gigasporarum' gen. nov., sp. nov., an endosymbiont of arbuscular mycorrhizal fungi. | arbuscular mycorrhizal fungi are obligate endosymbionts that colonize the roots of almost 80 % of land plants. the present paper describes morphological and molecular data on a bacterial endosymbiont living in the cytoplasm of dormant or germinating spores and symbiotic mycelia of the fungal species gigaspora margarita, scutellospora persica and scutellospora castanea. pcr amplification of almost the entire 16s rrna gene of the gigaspora margarita beg 34 endosymbiont, using universal bacterial p ... | 2003 | 12656162 |
| [study on the heterogeneity of lipopolysaccharides of ralstonia solanacearum]. | methods of electrophoresis in polyacrylamide gel in the system of sodium dodecyl sulphate (sds-page) with immunoblotting were used to investigate heterogeneity of lipopolysaccharides (lps) of ralstonia solanacearum (icmp 8110, 767, 5712, 7955, 7945, 7944, 8089 and 4157) which were characterized by various type structure of o-specific polysaccharides chains. when carrying out sds-page, it was determined that lps of all the investigated strains display bimodal distribution, typical of s-form lps a ... | 2002 | 12664545 |
| induction of resistance and expression of defense-related genes in tobacco leaves infiltrated with ralstonia solanacearum. | ralstonia solanacearum 8107 (8107) is non-pathogenic to tobacco and elicits the hypersensitive response (hr). in nicotiana tabacum cv. samsun nn leaves infiltrated with 8107, acquired resistance to challenging tobacco mosaic virus (tmv) was induced 2-6 d after 8107-infiltration. hsr203j and hin1 genes were expressed only in the 8107-infiltrated area. on the other hand, the expression of pr-1a and pr-1b genes was not detected in the 8107-infiltrated area, but in areas other than that developing t ... | 2003 | 12668775 |
| rational engineering of the regioselectivity of teca tetrachlorobenzene dioxygenase for the transformation of chlorinated toluenes. | the tetrachlorobenzene dioxygenase (teca) of ralstonia sp. ps12 carries out the first step in the aerobic biodegradation of chlorinated toluenes. besides dioxygenation of the aromatic ring of 4-chloro-, 2,4-, 2,5- and 3,4-dichlorotoluene as the main reaction, it also catalyses mono-oxygenation of the methyl groups of 2,3-, 2,6-, 3,5-di- and 2,4,5-trichlorotoluene as the main reactions, channelling these compounds into dead-end pathways. based on the crystal structure of the homologous naphthalen ... | 2003 | 12686633 |
| synergistic relationships in algal-bacterial microcosms for the treatment of aromatic pollutants. | the potential of algal-bacterial microcosms was studied for the biodegradation of salicylate, phenol and phenanthrene. the isolation and characterization of aerobic bacterial strains capable of mineralizing each pollutant were first conducted. ralstonia basilensis was isolated for salicylate degradation, acinetobacter haemolyticus for phenol and pseudomonas migulae and sphingomonas yanoikuyae for phenanthrene. the green alga chlorella sorokiniana was then cultivated in the presence of the pollut ... | 2003 | 12688473 |
| simple sequence repeats and compositional bias in the bipartite ralstonia solanacearum gmi1000 genome. | ralstonia solanacearum is an important plant pathogen. the genome of r. solananearum gmi1000 is organised into two replicons (a 3.7-mb chromosome and a 2.1-mb megaplasmid) and this bipartite genome structure is characteristic for most r. solanacearum strains. to determine whether the megaplasmid was acquired via recent horizontal gene transfer or is part of an ancestral single chromosome, we compared the abundance, distribution and composition of simple sequence repeats (ssrs) between both repli ... | 2003 | 12697060 |
| phosphate feeding strategy during production phase improves poly(3-hydroxybutyrate-co-3-hydroxyvalerate) storage by ralstonia eutropha. | the effect of a phosphate feeding strategy and the optimal rate of biomass production ( r(x)) during the production phase of p(3hb-co-3hv) in a 6-l fermentor were determined in cultures of ralstonia eutropha with the goal of enhancing polymer productivity. rates of biomass production ( r(x)) between 0.00 and 0.20 gx r l(-1) h(-1) were monitored during the production phase. when a low rate of cell growth was maintained ( r(x) of 0.02 gx r l(-1) h(-1)), polymer production improved, resulting in a ... | 2003 | 12698285 |
| [characterization of lipopolysaccharides from ralstonia solanacearum]. | lipopolysaccharides (lpss) from four strains of ralstonia solanacearum belonging to biovar i (icmp 6524, 8115, 5712, and 8169) were isolated and investigated. the structural components of the lps molecule, such as lipid a, the core oligosaccharide, and o-specific polysaccharide (o-ps), were obtained after mild acid hydrolysis of the lps preparations. in lipid a from all the lps samples studied, 3-hydroxyhexadecanoic, 2-hydroxyhexadecanoic, tetradecanoic, and hexadecanoic fatty acids prevailed. t ... | 2003 | 12698787 |
| removal of phenanthrene from soil by co-cultures of bacteria and fungi pregrown on sugarcane bagasse pith. | sixteen co-cultures composed of four bacteria and four fungi grown on sugarcane bagasse pith were tested for phenanthrene degradation in soil. the four bacteria were identified as pseudomonas aeruginose, ralstonia pickettii, pseudomonas sp. and pseudomonas cepacea. the four fungi were identified as: penicillium sp., trichoderma viride, alternaria tenuis and aspergillus terrus that were previously isolated from different hydrocarbon-contaminated soils. fungi had a statistically significant positi ... | 2003 | 12699938 |
| crystal structure of a full-length lysr-type transcriptional regulator, cbnr: unusual combination of two subunit forms and molecular bases for causing and changing dna bend. | the lysr-type transcriptional regulator (lttr) proteins are one of the most common transcriptional regulators in prokaryotes. here we report the crystal structure of cbnr, which is one of the lttrs derived from ralstonia eutropha nh9. this is the first crystal structure of a full-length lttr. cbnr was found to form a homo-tetramer, which seems to be a biologically active form. surprisingly, the tetramer can be regarded as a dimer of dimers, whereby each dimer is composed of two subunits in diffe ... | 2003 | 12706716 |
| [kinetic parameters of a culture of the hydrogen-oxidizing ralstonia eutropha, grown under the regimen of biosynthesis of polyhydroxybutyrate]. | kinetic parameters of a culture of the hydrogen-oxidizing bacterium ralstonia eutropha, grown on a gas substrate under the conditions favoring autotrophic biosynthesis of polyhydroxybutyrate, were studied. the following parameters, making it possible to control and optimize the process in industrial situations, were determined: specific rate of substrate consumption, physical properties of culture medium, and coefficients of heat emission and mass transfer. | 2003 | 12722652 |