Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
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| involvement of quinolinate phosphoribosyl transferase in promotion of potato growth by a burkholderia strain. | burkholderia sp. strain psjn stimulates root growth of potato explants compared to uninoculated controls under gnotobiotic conditions. in order to determine the mechanism by which this growth stimulation occurs, we used tn5 mutagenesis to produce a mutant, h41, which exhibited no growth-promoting activity but was able to colonize potato plants as well as the wild-type strain. the gene associated with the loss of growth promotion in h41 was shown to exhibit 65% identity at the amino acid level to ... | 2006 | 16391116 |
| coliform bacteria in sierra nevada wilderness lakes and streams: what is the impact of backpackers, pack animals, and cattle? | the presence of coliform bacteria indicates a watershed risk for harboring microbes capable of causing human disease. we hypothesized that water from watersheds that have different human- or animal-use patterns would have differing risks for the presence of coliform bacteria. methods; water was collected in wilderness areas of the sierra nevada range in california. a total of 60 sites from lakes or streams were selected to statistically differentiate the risk categories: 1) high use by backpacke ... | 2006 | 16538940 |
| light-driven hydrogen production by a hybrid complex of a [nife]-hydrogenase and the cyanobacterial photosystem i. | in order to generate renewable and clean fuels, increasing efforts are focused on the exploitation of photosynthetic microorganisms for the production of molecular hydrogen from water and light. in this study we engineered a 'hard-wired' protein complex consisting of a hydrogenase and photosystem i (hydrogenase-psi complex) as a direct light-to-hydrogen conversion system. the key component was an artificial fusion protein composed of the membrane-bound [nife] hydrogenase from the beta-proteobact ... | 2006 | 16542111 |
| molecular dynamics simulations of a cyclic-beta-(1-->2) glucan containing an alpha-(1-->6) linkage as a 'molecular alleviator' for the macrocyclic conformational strain. | the conformational preferences of a cyclic osmoregulated periplasmic glucan of ralstonia solanacearum (opgr), which is composed of 13 glucose units and linked entirely via beta-(1-->2) linkages excluding one alpha-(1-->6) linkage, were characterized by molecular dynamics simulations. of the three force fields modified for carbohydrates that were applied to select a suitable one for the cyclic glucan, the carbohydrate solution force field (csff) was found to most accurately simulate the cyclic mo ... | 2006 | 16546149 |
| thiolysis of poly(3-hydroxybutyrate) with polyhydroxyalkanoate synthase from ralstonia eutropha. | poly(3-hydroxybutyrate) (phb) is synthesized from 3-hydroxybutyryl-coa by polyhydroxyalkanoate synthase and hydrolyzed by phb depolymerase. in this study, we focused on the reverse reaction of polyhydroxyalkanoate synthase, and propose the possibility that phb can be degraded through a novel process, that is thiolysis of phb with coash. polyhydroxyalkanoate synthase of ralstonia eutropha was incubated with 14c-labeled phb and coash. the reaction mixture was fractionated by hplc and then analyzed ... | 2006 | 16567428 |
| identification of genomic islands in six plant pathogens. | genomic islands (gis) play important roles in microbial evolution, which are acquired by horizontal gene transfer. in this paper, the gis of six completely sequenced plant pathogens are identified using a windowless method based on z curve representation of dna sequences. consequently, four, eight, four, one, two and four gis are recognized with the length greater than 20-kb in plant pathogens agrobacterium tumefaciens str. c58, rolstonia solanacearum gmi1000, xanthomonas axonopodis pv. citri st ... | 2006 | 16581205 |
| sequencing and heterologous expression of an epimerase and two lyases from iminodisuccinate-degrading bacteria. | recently, degradation of all existing epimers of the complexing agent iminodisuccinate (ids) in the bacterial strain agrobacterium tumefaciens by6 was proven to depend on an epimerase and a c-n lyase (cokesa et al., appl. environ. microbiol. 70:3941-3947, 2004). in the bacterial strain ralstonia sp. strain slrs7, a corresponding c-n lyase is responsible for the initial degradation step (cokesa et al., biodegradation 15:229-239, 2004). the ite gene, encoding the ids-transforming epimerase, and th ... | 2006 | 16597988 |
| paralogs of genes encoding metal resistance proteins in cupriavidus metallidurans strain ch34. | cupriavidus (wautersia, ralstonia, alcaligenes) metallidurans strain ch34is a well-studied example of a metal-resistant proteobacterium. genome sequence analysis revealed the presence of a variety of paralogs of proteins that were previously shown to be involved in heavy metal resistance. which advantage has c. metallidurans in maintaining all these paralogs during evolution? paralogs investigated belong to the families rnd (resistance nodulation cell division) or chr (chromate resistance). the ... | 2006 | 16825791 |
| photoinduced hydrogen production by direct electron transfer from photosystem i cross-linked with cytochrome c3 to [nife]-hydrogenase. | the photosynthetic reaction center is an efficient molecular device for the conversion of light energy to chemical energy. in a previous study, we synthesized the hydrogenase/photosystem i (psi) complex, in which ralstonia hydrogenase was linked to the cytoplasmic side of synechocystis psi, to modify psi so that it photoproduced molecular hydrogen (h2). in that study, hydrogenase was fused with a psi subunit, psae, and the resulting hydrogenase-psae fusion protein was self-assembled with psae-fr ... | 2006 | 16836469 |
| ntlrp1, a tobacco leucine-rich repeat gene with a possible role as a modulator of the hypersensitive response. | plant defense responses against pathogens often involve the restriction of the pathogen to its site of penetration achieved through the combined effects of the hypersensitive response (hr) and its tightly connected localized acquired resistance (lar). the tobacco dd9-3 expressed sequence tag was previously isolated from a screen designed to isolate genes induced early during the hr, thus potentially involved in the induction/regulation of the hr or lar. translation of the open reading frame of d ... | 2006 | 16838787 |
| microbiology. bacteria help grow gold nuggets from dirt. | 2006 | 16840672 | |
| biomineralization of gold: biofilms on bacterioform gold. | bacterial biofilms are associated with secondary gold grains from two sites in australia. 16s ribosomal dna clones of the genus ralstonia that bear 99% similarity to the bacterium ralstonia metallidurans-shown to precipitate gold from aqueous gold(iii) tetrachloride-were present on all dna-positive gold grains but were not detected in the surrounding soils. these results provide evidence for the bacterial contribution to the authigenic formation of secondary bacterioform gold grains and nuggets. | 2006 | 16840703 |
| bacterial decontamination of duwl biofilm using oxygenal 6. | the aim of this study was bacteriological assessment of the dental unit waterlines (duwl) biofilm - concentration and composition of the aerobe and facultative anaerobe bacterial microflora, and evaluation of the influence of a disinfecting product, oxygenal 6, on the biofilm composition. tubing fragments were taken from 25 units twice, before and after disinfection, and bacterial suspension of the biofilm was obtained from the samples. the bacterial flora was determined with the plate culture m ... | 2006 | 16841887 |
| oxygen delivery device can also deliver infections. | 2006 | 16816625 | |
| identification of oxalotrophic bacteria by neural network analysis of numerical phenetic data. | a new approach with artificial neural network (ann) was applied to numerical taxonomy of bacteria using the oxalate as carbon and energy source. for this aim the characters effective in differentiating separate groups were selected from morphological, physiological and biochemical test results. fourteen aerobic, gram-negative, oxalate-utilizing isolates and four oxalate-utilizing reference strains (ralstonia eutropha dsm 428, methylobacterium extorquens dsm 1337t, ralstonia oxalatica dsm 1105t, ... | 2006 | 16821716 |
| gastrodia anti-fungal protein from the orchid gastrodia elata confers disease resistance to root pathogens in transgenic tobacco. | diseases of agricultural crops are caused by pathogens from several higher-order phylogenetic lineages including fungi, straminipila, eubacteria, and metazoa. these pathogens are commonly managed with pesticides due to the lack of broad-spectrum host resistance. gastrodia anti-fungal protein (gafp; gastrodianin) may provide a level of broad-spectrum resistance due to its documented anti-fungal activity in vitro and structural similarity to insecticidal lectins. we transformed tobacco (nicotiana ... | 2006 | 16858580 |
| metabolic engineering of strains of ralstonia eutropha and pseudomonas putida for biotechnological production of 2-methylcitric acid. | in this study strains of ralstonia eutropha h16 and pseudomonas putida kt2440 were engineered which are suitable for biotechnological production of 2-methylcitric acid (2mc). analysis of a previous mutant of r. eutropha able to accumulate 2mc recommended this strain as a candidate for fermentative production of 2mc. this knowledge was used for construction of strains of r. eutropha h16 and p. putida kt2440 capable of enhanced production of 2mc. in both bacteria the chromosomal genes encoding the ... | 2006 | 16876450 |
| regulation of class d beta-lactamase gene expression in ralstonia pickettii. | ralstonia pickettii, an environmental bacterium that may also be responsible for human infections, produces two unrelated, inducible and chromosomally encoded oxacillinases, oxa-22 and oxa-60. in order to study the molecular basis of the induction process of these oxacillinase genes, the induction kinetics, the promoter/operator regions necessary for expression and induction, and the role of several orfs located upstream and downstream of the bla(oxa) genes were investigated. the beta-lactamase ... | 2006 | 16946261 |
| diversifying selection drives the evolution of the type iii secretion system pilus of pseudomonas syringae. | the plant pathogenic bacterium pseudomonas syringae uses a type iii secretion system to inject virulence proteins directly into the cytoplasm of its hosts. the p. syringae type iii secretion apparatus is encoded, in part, by the hrpz operon, which carries the hrpa gene encoding the pilin subunit of the pilus, various components of the structural apparatus, and the hrpz harpin protein that is believed to produce pores in the host cell membrane. the pilus of the type iii system comes into direct c ... | 2006 | 16950758 |
| assay of poly(3-hydroxybutyrate) depolymerase activity and product determination. | two methods for accurate poly(3-hydroxybutyrate) (phb) depolymerase activity determination and quantitative and qualitative hydrolysis product determination are described. the first method is based on online determination of naoh consumption rates necessary to neutralize 3-hydroxybutyric acid (3hb) and/or 3hb oligomers produced during the hydrolysis reaction and requires a ph-stat apparatus equipped with a software-controlled microliter pump for rapid and accurate titration. the method is univer ... | 2006 | 16957234 |
| chemotaxis of ralstonia sp. sj98 towards p-nitrophenol in soil. | bioremediation of contaminated sites has been accepted as an efficient and cheaper alternative to physicochemical means of remediation in several cases. although chemotactic behaviour of many bacteria has been studied earlier and assays have been developed to study bacterial chemotaxis in semi-solid media, this phenomenon has never been demonstrated in soil. for bioremediation application it is important to know whether bacteria actually migrate through the heterogenous soil medium towards a gra ... | 2006 | 16958760 |
| physiological-biochemical properties and the ability to synthesize polyhydroxyalkanoates of the glucose-utilizing strain of the hydrogen bacterium ralstonia eutropha b8562. | physiological-biochemical, genetic, and cultural properties of the glucose-utilizing mutant strain ralstonia eutropha b8562 have been compared with those of its parent strain r. eutropha b5786. it has been shown that growth characteristics of the strain cultured on glucose as the sole carbon and energy source are comparable with those of the parent strain. strain b8562 is characterized by high polyhydroxyalkanoate (pha) yields on different carbon sources (co(2), fructose, and glucose). pha accum ... | 2006 | 16960738 |
| effects of mutations in the substrate-binding domain of poly[(r)-3-hydroxybutyrate] (phb) depolymerase from ralstonia pickettii t1 on phb degradation. | poly[(r)-3-hydroxybutyrate] (phb) depolymerase from ralstonia pickettii t1 (phaz(rpit1)) adsorbs to denatured phb (dphb) via its substrate-binding domain (sbd) to enhance dphb degradation. to evaluate the amino acid residues participating in dphb adsorption, phaz(rpit1) was subjected to a high-throughput screening system consisting of pcr-mediated random mutagenesis targeted to the sbd gene and a plate assay to estimate the effects of mutations in the sbd on dphb degradation by phaz(rpit1). gene ... | 2006 | 16963553 |
| genome sequence of the bioplastic-producing "knallgas" bacterium ralstonia eutropha h16. | the h(2)-oxidizing lithoautotrophic bacterium ralstonia eutropha h16 is a metabolically versatile organism capable of subsisting, in the absence of organic growth substrates, on h(2) and co(2) as its sole sources of energy and carbon. r. eutropha h16 first attracted biotechnological interest nearly 50 years ago with the realization that the organism's ability to produce and store large amounts of poly[r-(-)-3-hydroxybutyrate] and other polyesters could be harnessed to make biodegradable plastics ... | 2006 | 16964242 |
| genotypic diversity in a localized population of ralstonia solanacearum as revealed by random amplified polymorphic dna markers. | to assess genotypic diversity within ralstonia solanacearum isolates of a single field. | 2006 | 16968291 |
| bias from h2 cleavage to production and coordination changes at the ni-fe active site in the nad+-reducing hydrogenase from ralstonia eutropha. | the soluble nad+-reducing ni-fe hydrogenase (sh) from ralstonia eutropha h16 is remarkable because it cleaves hydrogen in the presence of dioxygen at a unique ni-fe active site (burgdorf et al. (2005) j. am. chem. soc. 127, 576). by x-ray absorption (xas), ftir, and epr spectroscopy, we monitored the structure and oxidation state of its metal centers during h2 turnover. in nadh-activated protein, a change occurred from the (cn)o2ni(ii)(mu-s)2fe(ii)(cn)3(co) site dominant in the wild-type sh to a ... | 2006 | 16981725 |
| ralstonia solanacearum requires f-box-like domain-containing type iii effectors to promote disease on several host plants. | the phytopathogenic bacterium ralstonia solanacearum encodes a family of seven type iii secretion system (t3ss) effectors that contain both a leucine-rich repeat and an f-box domain. this structure is reminiscent of a class of typical eukaryotic proteins called f-box proteins. the latter, together with skp1 and cullin1 subunits, constitute the scf-type e3 ubiquitin ligase complex and control specific protein ubiquitinylation. in the eukaryotic cell, depending on the nature of the polyubiquitin c ... | 2006 | 16983093 |
| metabolism of thioamides by ralstonia pickettii ta. | information on bacterial thioamide metabolism has focused on transformation of the antituberculosis drug ethionamide and related compounds by mycobacterium tuberculosis. to study this metabolism more generally, a bacterium that grew using thioacetamide as the sole nitrogen source was isolated via enrichment culture. the bacterium was identified as ralstonia pickettii and designated strain ta. cells grown on thioacetamide also transformed other thioamide compounds. transformation of the thioamide ... | 2006 | 16997975 |
| kinetics of 1,4-dioxane biodegradation by monooxygenase-expressing bacteria. | 1,4-dioxane is a probable human carcinogen, and an important emerging water contaminant. in this study, the biodegradation of dioxane by 20 bacterial isolates was evaluated, and 13 were found to be capable of transforming dioxane. dioxane served as a growth substrate for pseudonocardia dioxanivorans cb1190 and pseudonocardia benzenivorans b5, with yields of 0.09 g protein g dioxane(-1) and 0.03 g protein g dioxane(-1), respectively. cometabolic transformation of dioxane was observed for monooxyg ... | 2006 | 16999122 |
| physiological changes induced in four bacterial strains following oxidative stress. | in order to study the behaviour and resistance of bacteria under extreme conditions, physiological changes associated with oxidative stress were monitored using flow cytometry. the study was conducted to assess the maintenance of membrane integrity and potential as well as the esterase activity, the intracellular ph and the production of superoxide anions in four bacterial strains (ralstonia metallidurans, escherichia coli, shewanella oneidensis and deinococcus radiodurans). the strains were cho ... | 2006 | 17022450 |
| mutations in the lrpe gene of ralstonia solanacearum affects hrp pili production and virulence. | the ralstonia solanacearum hrpb-regulated gene lrpe (hpx5/brg24) encodes a popc-like leucine-rich repeat (lrr) protein that carries 11 tandem lrr in the central region. defects in the lrpe gene slightly reduced the virulence of r. solanacearum on host plants and changed the bacterial morphology leading to the formation of large aggregates in a minimal medium. the aggregation in the deltalrpe background required the presence of a functional hrp type iii secretion system. in wild-type r. solanacea ... | 2006 | 16903354 |
| coselection for microbial resistance to metals and antibiotics in freshwater microcosms. | bacterial resistances to diverse metals and antibiotics are often genetically linked, suggesting that exposure to toxic metals may select for strains resistant to antibiotics and vice versa. to test the hypothesis that resistances to metals and antibiotics are coselected for in environmental microbial assemblages, we investigated the frequency of diverse resistances in freshwater microcosms amended with cd, ni, ampicillin or tetracycline. we found that all four toxicants significantly increased ... | 2006 | 16913911 |
| improved inverse pcr scheme for metagenome walking. | inverse pcr has been used for the recovery of genome regions flanking a known sequence, although its application to metagenome walking is limited due to inefficient amplification from low copy number fragments. here we present an improved inverse pcr scheme that enables walking of rare fragments in environmental metagenomes. our scheme includes the following steps: (i) inverse pcr in which one primer is connected to an affinity tag; (ii) affinity purification of pcr products for removing backgro ... | 2006 | 16925020 |
| integrated regulation of the type iii secretion system and other virulence determinants in ralstonia solanacearum. | in many plant and animal bacterial pathogens, the type iii secretion system (ttss) that directly translocates effector proteins into the eukaryotic host cells is essential for the development of disease. in all species studied, the transcription of the ttss and most of its effector substrates is tightly regulated by a succession of consecutively activated regulators. however, the whole genetic programme driven by these regulatory cascades is still unknown, especially in bacterial plant pathogens ... | 2006 | 16933989 |
| characterization of two 3-hydroxybutyrate dehydrogenases in poly(3-hydroxybutyrate)-degradable bacterium, ralstonia pickettii t1. | two d-(-)-3-hydroxybutyrate (3hb) dehydrogenases, bdh1 and bdh2, were isolated and purified from a poly(3-hydroxybutyrate) (phb)-degradable bacterium, ralstonia pickettii t1. bdh1 activity increased in r. pickettii t1 cells grown on several organic acids as a carbon source but not on 3hb, whereas bdh2 activity markedly increased in the same cells grown on 3hb or phb. to examine their biochemical properties, bdh1 and bdh2 were cloned and overexpressed in escherichia coli, and their purified produ ... | 2006 | 16935252 |
| regulation of the type iii secretion system in phytopathogenic bacteria. | the type iii secretion system (ttss) is a specialized protein secretion machinery used by numerous gram-negative bacterial pathogens of animals and plants to deliver effector proteins directly into the host cells. in plant-pathogenic bacteria, genes encoding the ttss were discovered as hypersensitive response and pathogenicity (hrp) genes, because mutation of these genes typically disrupts the bacterial ability to cause diseases on host plants and to elicit hypersensitive response on nonhost pla ... | 2006 | 17073299 |
| the ralstonia eutropha h16 phasin phap1 is targeted to intracellular triacylglycerol inclusions in rhodococcus opacus pd630 and mycobacterium smegmatis mc2155, and provides an anchor to target other proteins. | in ralstonia eutropha, the h16 phasin phap1 represents the major phasin that binds to the surface of polyhydroxyalkanoate (pha) inclusions. in this study, c-terminal fusions of phap1 with enhanced green fluorescent protein (egfp) and with escherichia coli beta-galactosidase (lacz) were expressed separately in the triacylglycerol (tag)-accumulating actinomycetes rhodococcus opacus pd630 and mycobacterium smegmatis mc(2)155, employing the m. smegmatis acetamidase (ace) promoter of the escherichia- ... | 2006 | 17074898 |
| electricity from low-level h2 in still air--an ultimate test for an oxygen tolerant hydrogenase. | we demonstrate an extreme test of o(2) tolerance for a biological hydrogen-cycling catalyst: the generation of electricity from just 3% h(2) released into still, ambient air using an open fuel cell comprising an anode modified with the unusual hydrogenase from ralstonia metallidurans ch34, that oxidizes trace h(2) in atmospheric o(2), connected via a film of electrolyte to a cathode modified with the fungal o(2) reductase, laccase. | 2006 | 17146518 |
| fermentative production of (r)-(-)-3-hydroxybutyrate using 3-hydroxybutyrate dehydrogenase null mutant of ralstonia eutropha and recombinant escherichia coli. | two systems, one using an (r)-(-)-3-hydroxybutyrate dehydrogenase (bdh) null mutant of ralstonia eutropha and the other using a recombinant escherichia coli strain containing a synthetic poly[(r)-(-)-3-hydroxybutyrate] (phb) operon and an extracellular phb depolymerase gene, were used for the fermentative production of (r)-(-)-3-hydroxybutyrate (3hb). the concentration of 3hb in the culture supernatant of the mutant r. eutropha system reached about 30 mm after 5 d under anaerobic conditions, alt ... | 2006 | 17270718 |
| [isolation and ardra analysis of cucumber entophytic antagonists against ralstonia solanacearum]. | cucumber bacteria wilt, caused by ralstonia solanacearum, is one of soilborne plant diseases of worldwide origin. biological control is considered the most environment-safe and efficacious approaches to control this disease. in this study, a total of 469 entophytic bacteria were isolated from cucumber plant roots at different growth stages and 59 of these isolates were shown antagonistic against ralstonia solanacearum. an analysis of the level of biodiversity of the isolates at the species level ... | 2006 | 17302166 |
| occurrence and expression of tricarboxylate synthases in ralstonia eutropha. | 2-methylcitrate synthase (2-mcs1) and citrate synthase (cs) of ralstonia eutropha strain h16 were separated by affinity chromatography and analyzed for their substrate specificities. 2-mcs1 used not only the primary substrate propionyl-coa but also acetyl-coa and, at a low rate, even butyryl-coa and valeryl-coa for condensation with oxaloacetate. the km values for propionyl-coa and acetyl-coa were 0.061 or 0.35 mm, respectively. this enzyme is therefore a competitor for acetyl-coa during biosynt ... | 2006 | 16133321 |
| utilization of capsaicin and vanillylamine as growth substrates by capsicum (hot pepper)-associated bacteria. | capsaicin contributes to the organoleptic attributes of hot peppers. here, we show that capsaicin is utilized as a growth nutrient by certain bacteria. enrichment cultures utilizing capsaicin were successfully initiated using capsicum-derived plant material or leaves of tomato (a related solanaceae) as inocula. no other sources of inoculum examined yielded positive enrichments. of 25 isolates obtained from enrichments: all utilized 8-methylnonanoic acid; nine were found capable of degrading caps ... | 2006 | 16478462 |
| tetratricopeptide repeats are essential for pcrh chaperone function in pseudomonas aeruginosa type iii secretion. | the type iii secretion system (t3ss) is a specialized apparatus evolved by gram-negative bacteria to deliver effector proteins into host cells, thus facilitating the establishment of an infection. effector translocation across the target cell plasma membrane is believed to occur via pores formed by at least two secreted translocator proteins, the functions of which are dependent upon customized class ii t3ss chaperones. recently, three internal tetratricopeptide repeats (tprs) were identified in ... | 2006 | 16487320 |
| biotoxicity assessment on reusability of municipal solid waste incinerator (mswi) ash. | this study provides a first attempt of dose-response analysis and margin of safety using escherichia coli dh5alpha, bacillus subtilis as indicator microorganisms to put forward, in general terms and explanations, the toxicity rankings of various ashes of municipal solid waste incinerator (mswi) for feasibility in further applications. since the mswi ash often contains cations of si, ca, al and fe, it is frequently considered to be recycled for construction building-materials. growth inhibition o ... | 2006 | 16490305 |
| a lower specificity phac2 synthase from pseudomonas stutzeri catalyses the production of copolyesters consisting of short-chain-length and medium-chain-length 3-hydroxyalkanoates. | a polyhydroxyalkanoate (pha) synthase gene phac2 (ps) from pseudomonas stutzeri strain 1317 was introduced into a pha synthase gene phbc (re) negative mutant, ralstonia eutropha phb(-)4. it conferred on the host strain the ability to synthesize pha, the monomer compositions of which varied widely when grown on different carbon sources. during cultivation on gluconate, the presence of phac2 (ps) in r. eutropha phb(-)4 led to the accumulation of polyhydroxybutyrate (phb) homopolymer in an amount o ... | 2006 | 16496091 |
| assessing nickel bioavailability in smelter-contaminated soils. | metal contaminants in soil environments derived from industrial pollution have clearly established the need for research on bioavailability and potential health risks. much research has been conducted on metal sorption in soils. however, there is still a need to better understand the availability of metal contaminants to plants and microbes. such information will enhance both human health and decisions about remediation efforts. in this study, welland loam (typic epiaquoll) and quarry muck (terr ... | 2006 | 16499951 |
| differentiation of species combined into the burkholderia cepacia complex and related taxa on the basis of their fatty acid patterns. | using the established commercial system sherlock (midi, inc.), cellular fatty acid methyl ester analysis for differentiation among burkholderia cepacia complex species was proven. the identification key based on the diagnostic fatty acids is able to discern phenotypically related ralstonia pickettii and pandoraea spp. and further distinguish burkholderia pyrrocinia, burkholderia ambifaria, and burkholderia vietnamiensis. | 2006 | 16517920 |
| crystal structure of 3-hydroxyanthranilic acid 3,4-dioxygenase from saccharomyces cerevisiae: a special subgroup of the type iii extradiol dioxygenases. | 3-hydroxyanthranilic acid 3,4-dioxygenase (3hao) is a non-heme ferrous extradiol dioxygenase in the kynurenine pathway from tryptophan. it catalyzes the conversion of 3-hydroxyanthranilate (haa) to quinolinic acid (quin), an endogenous neurotoxin, via the activation of n-methyl-d-aspartate (nmda) receptors and the precursor of nad(+) biosynthesis. the crystal structure of 3hao from s. cerevisiae at 2.4 a resolution shows it to be a member of the functionally diverse cupin superfamily. the struct ... | 2006 | 16522801 |
| an endoglucanase is involved in infection of rice roots by the not-cellulose-metabolizing endophyte azoarcus sp. strain bh72. | the nitrogen-fixing endophyte azoarcus sp. strain bh72 infects roots of kallar grass and rice inter- and intra-cellularly and can spread systemically into shoots without causing symptoms of plant disease. although cellulose or its breakdown products do not support growth, this strain expresses an endoglucanase, which might be involved in infection. sequence analysis of egla places the secreted 34-kda protein into the glycosyl hydrolases family 5, with highest relatedness (40% identity) to endogl ... | 2006 | 16529380 |
| a tyrosinase with an abnormally high tyrosine hydroxylase/dopa oxidase ratio. | the sequencing of the genome of ralstonia solanacearum[salanoubat m, genin s, artiguenave f, et al. (2002) nature 415, 497-502] revealed several genes that putatively code for polyphenol oxidases (ppos). this soil-borne pathogenic bacterium withers a wide range of plants. we detected the expression of two ppo genes (accession numbers np_518458 and np_519622) with high similarity to tyrosinases, both containing the six conserved histidines required to bind the pair of type-3 copper ions at the ac ... | 2006 | 16403014 |
| identification of open reading frames unique to a select agent: ralstonia solanacearum race 3 biovar 2. | an 8x draft genome was obtained and annotated for ralstonia solanacearum race 3 biovar 2 (r3b2) strain uw551, a united states department of agriculture select agent isolated from geranium. the draft uw551 genome consisted of 80,169 reads resulting in 582 contigs containing 5,925,491 base pairs, with an average 64.5% gc content. annotation revealed a predicted 4,454 protein coding open reading frames (orfs), 43 trnas, and 5 rrnas; 2,793 (or 62%) of the orfs had a functional assignment. the uw551 ... | 2006 | 16404955 |
| bioluminescent monitoring of turbulent bioconvection. | under adjusted experimental conditions, open-to-air cultures of lux gene-engineered ralstonia eutropha (wholecell biosensors of copper) exhibit bioconvection, which accounts for fluctuating bioluminescence. the power spectrum of bioluminescence intensity fluctuations recorded from a cylindrical sample 9 mm in diameter and approximately 10 mm in height is characterized by a dominant low-frequency oscillation (with a characteristic period of approximately 8-12 min), which is occasionally accompani ... | 2006 | 16416487 |
| no-dependent transcriptional activation of gene expression in ralstonia eutropha h16. | the sigma54-dependent transcriptional regulator norr of ralstonia eutropha h16 activates gene expression in response to nitric oxide (no). the n-terminal domain of norr is thought to be involved in signal perception. a c112s exchange within this domain abolished promoter activation by the mutated protein, indicating that cys(112) is essential for the signalling mechanism of norr. the dna region recognized by norr contains three copies of a conserved element termed the norr-box. alteration of bas ... | 2006 | 16417516 |
| an improved purification procedure for the soluble [nife]-hydrogenase of ralstonia eutropha: new insights into its (in)stability and spectroscopic properties. | infrared (ir) spectra in combination with chemical analyses have recently shown that the active ni-fe site of the soluble nad(+)-reducing [nife]-hydrogenase from ralstonia eutropha contains four cyanide groups and one carbon monoxide as ligands. experiments presented here confirm this result, but show that a variable percentage of enzyme molecules loses one or two of the cyanide ligands from the active site during routine purification. for this reason the redox conditions during the purification ... | 2006 | 16418856 |
| site-directed mutagenesis of gentisate 1,2-dioxygenases from klebsiella pneumoniae m5a1 and ralstonia sp. strain u2. | gentisate 1,2-dioxygenase (gdo, ec 1.13.11.4) is the first enzyme in gentisate pathway that catalyses the ring fission of gentisate to form maleylpyruvate. phylogenetic tree of amino acid sequences from 11 gdos demonstrates that the gdos from different genus share identities between 12.1% and 64.8%. according to the alignment result, four highly conserved histidine residues in gdo from klebsiella pneumoniae m5a1 and ralstonia sp. strain u2 were chosen to be substituted with aspartate residues. e ... | 2006 | 16427517 |
| optimization of cyanophycin production in recombinant strains of pseudomonas putida and ralstonia eutropha employing elementary mode analysis and statistical experimental design. | elementary mode analysis was applied to simulate conditions for cyanophycin (cgp) biosynthesis and to optimize its production in bacteria. the conclusions from these simulations were confirmed by experiments with recombinant strains of the wild types and polyhydroxyalkanoate (pha)-negative mutants of ralstonia eutropha and pseudomonas putida expressing cgp synthetase genes (cpha) of synechocystis sp. strain pcc6308 or anabaena sp. strain pcc7120. in particular, the effects of suitable precursor ... | 2006 | 16435401 |
| production and properties of the native chromobacterium violaceum fucose-binding lectin (cv-iil) compared to homologous lectins of pseudomonas aeruginosa (pa-iil) and ralstonia solanacearum (rs-iil). | chromobacterium violaceum is a versatile, violet pigment (violacein)-producing beta-proteobacterium, confined to tropical and subtropical regions, dwelling in soil and water, like pseudomonas aeruginosa and ralstonia solanacearum. these three bacteria are saprophytes that occasionally become aggressive opportunistic pathogens virulently attacking animals (the first two) and plants (the third). the recent availability of their genome sequences enabled identification in the c. violaceum genome of ... | 2006 | 16436433 |
| ralstonia pickettii-innocent bystander or a potential threat? | 2006 | 16441445 | |
| nitrous oxide reductase genes (nosz) of denitrifying microbial populations in soil and the earthworm gut are phylogenetically similar. | earthworms emit nitrous oxide (n2o) and dinitrogen (n2). it has been hypothesized that the in situ conditions of the earthworm gut activates ingested soil denitrifiers during gut passage and leads to these in vivo emissions (m. a. horn, a. schramm, and h. l. drake, appl. environ. microbiol. 69:1662-1669, 2003). this hypothesis implies that the denitrifiers in the earthworm gut are not endemic to the gut but rather are regular members of the soil denitrifier population. to test this hypothesis, t ... | 2006 | 16461644 |
| the naphthalene catabolic (nag) genes of polaromonas naphthalenivorans cj2: evolutionary implications for two gene clusters and novel regulatory control. | polaromonas naphthalenivorans cj2, found to be responsible for the degradation of naphthalene in situ at a coal tar waste-contaminated site (c.-o. jeon et al., proc. natl. acad. sci. usa 100:13591-13596, 2003), is able to grow on mineral salts agar media with naphthalene as the sole carbon source. beginning from a 484-bp nagac-like region, we used a genome walking strategy to sequence genes encoding the entire naphthalene degradation pathway andadditional flanking regions. we found that the naph ... | 2006 | 16461653 |
| enzymatic recovery and purification of polyhydroxybutyrate produced by ralstonia eutropha. | polyhydroxybutyrate (phb) is the most studied among a wide variety of polyhydroxyalkanoates, bacterial biodegradable polymers known as potential substitutes for conventional plastics. this work aimed at evaluating the use of enzymes to recover and purify the phb produced by ralstonia eutropha dsm545. screening experiments allowed the selection of trypsin, bromelain and lysozyme among six enzymes, based on their efficiency in lysing cells of a non-phb producing r. eutropha strain. then, process c ... | 2006 | 16253372 |
| application of a kdpg-aldolase gene-dependent addiction system for enhanced production of cyanophycin in ralstonia eutropha strain h16. | two different recombinant plasmids both containing the cyanophycin synthetase gene (cpha) of synechocystis sp. strain pcc6308 but differing concerning the resistance marker gene were tested for their suitability to produce high amounts of cyanophycin in recombinant strains of ralstonia eutropha. various cultivation experiments at the 30-l scale revealed very low cyanophycin contents of the cells ranging from 4.6% to 6.2% (w/w) of cellular dry weight (cdw) only, most probably because most cells h ... | 2006 | 16266816 |
| ralstonia pickettii: a persistent gram-negative nosocomial infectious organism. | non-fermenting gram-negative bacilli create a significant problem in clinical settings, being a widespread cause of nosocomial infections. they are opportunistic pathogens that take advantage of underlying conditions and diseases. ralstonia pickettii, a non-fermenting gram-negative bacillus, is regarded as being of minor clinical significance; however, many instances of infections with this organism are reported in the literature. infections can include bacteraemia/septicaemia caused by contamin ... | 2006 | 16337309 |
| sequential removal of heavy metals ions and organic pollutants using an algal-bacterial consortium. | the residual algal-bacterial biomass from photosynthetically supported, organic pollutant biodegradation processes, in enclosed photobioreactors, was tested for its ability to accumulate cu(ii), ni(ii), cd(ii), and zn(ii). salicylate was chosen as a model contaminant. the algal-bacterial biomass combined the high adsorption capacity of microalgae with the low cost of the residual biomass, which makes it an attractive biosorbent for environmental applications. cu(ii) was preferentially taken-up f ... | 2006 | 16307789 |
| microbial and kinetic characterization of pure and mixed cultures aerobically degrading 4-nitrophenol. | the molecular and kinetic characterization of a microorganism able to aerobically degrade 4-nitrophenol (4np) is presented. the microorganism was isolated from a mixed culture operating in a laboratory-scale sequencing batch reactor with an aerobic anoxic cycle. it was identified as a member of ralstonia genus within betaproteobacteria. it is a gram negative coccobacillum (cell length of 2-3 microm) able to aerobically store lipid inclusions when grown aerobically on nitrophenol as the sole carb ... | 2006 | 16309731 |
| dispersion optimization to enhance phb production in fed-batch cultures of ralstonia eutropha. | despite its many useful properties, microbial production of poly-beta-hydroxybutyrate (phb) is not yet commercially competitive with synthetic polymers. one reason is inadequate optimization of the fermentation under industrial conditions. in this study, a physiologically reasonable and experimentally validated kinetic model for phb synthesis by ralstonia eutropha was incorporated into a dispersion model to simulate a large fed-batch bioreactor. solutions of the model indicated that cell growth ... | 2006 | 16289872 |
| effect of expressing polyhydroxybutyrate synthesis genes (phbcab) in streptococcus zooepidemicus on production of lactic acid and hyaluronic acid. | hyaluronic acid (ha) has been industrially produced using the gram-positive bacterium streptococcus zooepidemicus. large amount of lactic acid formation was one of the important factors that restricted cell growth and ha productivity and lowered the substrate to ha conversion efficiency in a fermentor. in this study, polyhydroxybutyrate (phb) synthesis genes (phbcab) of ralstonia eutropha were cloned from the plasmid pbhr68 and were inserted into the plasmid peu308, an expression vector for gram ... | 2006 | 16292535 |
| production and purification of self-assembling peptides in ralstonia eutropha. | self-assembling peptides have emerged as an attractive scaffold material for tissue engineering, yet the expense associated with solid phase chemical synthesis has limited their broad use. in addition, the fidelity of chemical synthesis constrains the length of polypeptides that can be produced homogeneously by this method. template-derived biosynthesis by recombinant dna technology may overcome both of these problems. however, recovery of polypeptides from recombinant protein expression systems ... | 2006 | 16249097 |
| biodegradation of dichloromethane by the polyvinyl alcohol-immobilized methylotrophic bacterium ralstonia metallidurans pd11. | a dichloromethane (dcm)-degrading bacterium, ralstonia metallidurans pd11 nbrc 101272, was immobilized in a polyvinyl alcohol (pva) gel to use in a bioreactor for dcm treatment. after 4-month incubation of pva gel beads with r. metallidurans pd11 and dcm in a mineral salt medium, the cells were tightly packed in the mesh of the gel. forty beads of the gel in 10 ml of a batch system model showed effective activity degrading 500 and 1,000 mg l(-1) dcm within 2 and 3 h, respectively. although reduc ... | 2006 | 16249875 |
| production system for biodegradable polyester polyhydroxybutyrate by corynebacterium glutamicum. | a biosynthetic pathway for poly(3-hydroxybutyrate) [p(3hb)] production by corynebacterium glutamicum was developed by introducing the phbcab operon derived from ralstonia eutropha. p(3hb) synthase activity was detected in this recombinant c. glutamicum carrying a cell surface protein gene promoter. intracellular p(3hb) was microscopically observed as inclusion granules and its content was calculated to be 22.5% (w/w) with a number average molecular weight of 2.1x10(5) and a polydispersity of 1.6 ... | 2006 | 17046539 |
| growth on dichlorobiphenyls with chlorine substitution on each ring by bacteria isolated from contaminated african soils. | until recently, it was generally believed that the presence of more than one chlorine substituent prevented chlorinated biphenyls from serving as a sole source of carbon and energy for aerobic bacteria. in this study, we report the isolation of three aerobic strains, identified as enterobacter sp. sa-2, ralstonia sp. sa-4, and pseudomonas sp. sa-6 from nigerian polluted soils, that were able to grow on a wide range of dichlorobiphenyls (dicbs). in addition to growing on all monochlorobiphenyls ( ... | 2007 | 17047953 |
| substrate consumption and biomass growth of ralstonia eutropha at various s0/x0 levels in batch cultures. | the biomass growth, substrate consumption and polyhydrobutyrate (phb) production of ralstonia eutropha with butyric acid and fructose as the carbon and energy sources at various ratios of initial substrate concentration (s0) to initial biomass concentration (x0) were investigated in this study. results indicated that the phb content increased with the increasing s0/x0 ratio. different substrates exhibited a similar trend for cell growth and substrates consumption with the changing s0/x0 ratio. t ... | 2007 | 17071078 |
| induction of a small heat shock protein and its functional roles in nicotiana plants in the defense response against ralstonia solanacearum. | in tobacco (nicotiana tabacum), ralstonia solanacearum oe1-1 (rsoe1-1) is pathogenic, whereas r. solanacearum 8107 (rs8107) is nonpathogenic and induces the hypersensitive response (hr). to elucidate the molecular mechanisms of plant-r. solanacearum interactions, we used differential display to isolate a cdna fragment, a6, regulated in tobacco by inoculation with rsoe1-1. the deduced amino acid sequence predicted from full-length a6-cdna showed similarity to small heat shock proteins from arabid ... | 2007 | 17965181 |
| naphthalene metabolism and growth inhibition by naphthalene in polaromonas naphthalenivorans strain cj2. | this study was designed to characterize naphthalene metabolism in polaromonas naphthalenivorans cj2. comparisons were completed using two archetypal naphthalene-degrading bacteria: pseudomonas putida ncib 9816-4 and ralstonia sp. strain u2, representative of the catechol and gentisate pathways, respectively. strain cj2 carries naphthalene catabolic genes that are homologous to those in ralstonia sp. strain u2. here we show that strain cj2 metabolizes naphthalene via gentisate using respirometry, ... | 2007 | 17975081 |
| analyses of six homologous proteins of protochlamydia amoebophila uwe25 encoded by large gc-rich genes (lgr): a model of evolution and concatenation of leucine-rich repeats. | along the chromosome of the obligate intracellular bacteria protochlamydia amoebophila uwe25, we recently described a genomic island pam100g. it contains a tra unit likely involved in conjugative dna transfer and lgre, a 5.6-kb gene similar to five others of p. amoebophila: lgra to lgrd, lgrf. we describe here the structure, regulation and evolution of these proteins termed lgrs since encoded by "large g+c-rich" genes. | 2007 | 18021397 |
| 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 |
| microbial diversity in pharmaceutical product recalls and environments. | identification of microbial contaminants in product recalls and environmental samples provides important information on the possible contamination sources and distribution of microbial species in pharmaceutical environments. analysis of fda product recall data for 134 non-sterile pharmaceutical products from 1998 to september 2006 demonstrated that 48% of recalls were due to contamination by either burkholderia cepacia, pseudomonas spp., or ralstonia picketti, while yeast and mold contamination ... | 2007 | 18047177 |
| two bacterial entophytes eliciting both plant growth promotion and plant defense on pepper (capsicum annuum l.). | plant growth-promoting rhizobacteria (pgpr) have the potential to be used as microbial inoculants to reduce disease incidence and severity and to increase crop yield. some of the pgpr have been reported to be able to enter plant tissues and establish endophytic populations. here, we demonstrated an approach to screen bacterial endophytes that have the capacity to promote the growth of pepper seedlings and protect pepper plants against a bacterial pathogen. initially, out of 150 bacterial isolate ... | 2007 | 18051359 |
| [microbial diversity in scorpion intestine (buthus martensii karsch)]. | scorpion is an important officinal animal, and has a high nutritional value. in this study, the culture-independent and culture-dependent methods were used to investigate the microbial diversity in the scorpion's intestine. results based on culture-independent method showed the bacteria to be related to alpha, beta, gamma-proteobacteria. bacteria isolated by the culture-dependent method were high g + c, gram-positive bacteria. the genera enterobacter, serratia and ochrobactrum were detected by b ... | 2007 | 18062268 |
| [analysis of signal peptides of the secreted proteins in ralstonia solanacearum gmi1000]. | the 3,440 open reading frames (orfs) of ralstonia solanacearum gmi1000 were used for predicting signal peptides by comprehensive analyses with signalp 3.0, tmhmm 2.0, targetp 1.01, lipop 1.0 and psortb, and screening based on l value. total 186 signal peptides with conserved amino acid residues are found and among them, 134 are secretary types, 22 are rr-motif types and 30 are lipoprotein signal peptides. the length distribution of signal peptide and its domains were analyzed systemically. no ty ... | 2007 | 17989054 |
| pcr-based specific detection of ralstonia solanacearum by amplification of cytochrome c1 signal peptide sequences. | a polymerase chain reaction (pcr)-based method was developed to detect the dna of ralstonia solanacearum, the causal agent of bacterial wilt in various crop plants. one pair of primers (ralsf and ralsr), designed using cytochrome c1 signal peptide sequences specific to r. solanacearum, produced a pcr product of 932 bp from 13 isolates of r. solanacearum from several countries. the primer specificity was then tested using dna from 21 isolates of ralstonia, pseudomonas, burkholderia, xanthomonas, ... | 2007 | 18092459 |
| monitoring of phytopathogenic ralstonia solanacearum cells using green fluorescent protein-expressing plasmid derived from bacteriophage phirss1. | a green fluorescent protein (gfp)-expressing plasmid was constructed from a filamentous bacteriophage phirss1 that infects the phytopathogen ralstonia solanacearum. this plasmid designated as prss12 (4.7 kbp in size) consists of an approximately 2248 bp region of the phirss1 rf dna, including orf1-orf3 and the intergenic region (ig), and a km cassette in addition to the gfp gene. it was easily introduced by electroporation and stably maintained even without selective pressure in strains of r. so ... | 2007 | 18215630 |
| improvement of poly(3-hydroxybutyrate) [p(3hb)] production in corynebacterium glutamicum by codon optimization, point mutation and gene dosage of p(3hb) biosynthetic genes. | in our previous study, a system for producing poly(3-hydroxybutyrate) [p(3hb)] was established by introducing a polyhydroxyalkanoate (pha) biosynthetic gene operon (phacab re) derived from ralstonia eutropha into corynebacterium glutamicum. in this study, two experimental strategies have been applied to improve p(3hb) production in recombinant c. glutamicum. one is a codon optimization of the n-terminal-coding region of the pha synthase (phac re) gene focusing on the codon usage preference for t ... | 2007 | 18215631 |
| [screening, identification, and antagonism assessment, of dominant bacteria in ageratina adenophora sprengel rhizosphere soil]. | by using isolation and culture method, 25 strains of dominant bacteria in ageratina adenophora rhizosphere soil were isolated and identified, of which, 8 strains were assessed for their antagonistic activity. the results showed that bacillus and pseudomonas were highly abundant in a. adenophora rhizosphere soil, of which, b. subtilis and b. megaterium were most abundant and occupied 55.6% of the total identified bacteria. these dominant bacteria had different level antagonistic activity to fusar ... | 2007 | 18333457 |
| diversity of ralstonia solanacearum infecting eggplant in the philippines. | abstract the diversity of ralstonia solanacearum strains isolated from eggplant (solanum melongena) grown in five provinces of the philippine island group of luzon was assessed using a recently described hierarchical system. all strains keyed to race 1, biovar 3 or 4. phylotype-specific multiplex polymerase chain reaction (pcr) indicated that, like most other strains of asian origin, all the strains in our philippine collection belong to phylotype i. taxometric and phylogenetic analyses of parti ... | 2007 | 18943517 |
| resistance enhancement of transgenic tomato to bacterial pathogens by the heterologous expression of sweet pepper ferredoxin-i protein. | abstract expression of a foreign gene to enhance plant disease resistance to bacterial pathogens is a favorable strategy. it has been demonstrated that expressing sweet pepper ferredoxin-i protein (pflp) in transgenic plants can enhance disease resistance to bacterial pathogens that infect leaf tissue. in this study, pflp was applied to protect tomato (lycopersicon esculentum cv. cherry cln1558a) from the root-infecting pathogen, ralstonia solanacearum. independent r. solanacearum resistant t(1) ... | 2007 | 18943629 |
| isolation and identification of atrazine-degrading bacteria from corn field soil in fars province of iran. | in this study several agricultural fields with a long history of atrazine application in fars province of iran have been explored for their potential of atrazine biodegradation. after several subculturing for a period of 300 days acclimation, leads to an enhancement of atrazine biodegradation rate. a successful enrichment culture with a high capability for atrazine degradation was obtained (88%). a combination of enrichment culture technique, in a basal salt medium containing atrazine and carbon ... | 2007 | 19069990 |
| isolation and characterisation of ralstonia solanacearum strains from solanaceae crops in ethiopia. | eighty one isolates of ralstonia solanacearum -like bacteria on triphenyl tetrazolium chloride (ttc) medium were collected from different solanaceae crops (i.e. potato, tomato and pepper plants and potato tubers) at various sites in ethiopia. of these, 62 strains were identified as r. solanacearum based on their cultural characteristics on ttc medium, tomato pathogenicity bioassay, carbon source utilisation patterns and a specific pcr-based assay. by hayward's classification method, based on car ... | 2007 | 17304617 |
| characterization of the interaction between the bacterial wilt pathogen ralstonia solanacearum and the model legume plant medicago truncatula. | the soilborne pathogen ralstonia solanacearum is the causal agent of bacterial wilt and attacks more than 200 plant species, including some legumes and the model legume plant medicago truncatula. we have demonstrated that m. truncatula accessions jemalong a17 and f83005.5 are susceptible to r. solanacearum and, by screening 28 r. solanacearum strains on the two m. truncatula lines, differential interactions were identified. r. solanacearum gmi1000 infected jemalong a17 line, and disease symptoms ... | 2007 | 17313167 |
| biosynthesis of polyhydroxybutyrate (phb) and extracellular polymeric substances (eps) by ralstonia eutropha atcc 17699 in batch cultures. | the production of polyhydroxybutyrate (phb) and extracellular polymeric substances (eps) by ralstonia eutropha atcc 17699 at various glucose and (nh4)2so4 concentrations in batch cultures were investigated. the biosynthesis of eps by r. eutropha closely coupled with cell growth, while phb was synthesized only under nitrogen-deficient and cell-growth-limited conditions. experimental results show that the specific phb production rate had an exponential correlation with both specific cell growth ra ... | 2007 | 17318537 |
| genetic characterization of 2,4,6-trichlorophenol degradation in cupriavidus necator jmp134. | the degradation pathway of 2,4,6-trichlorophenol (2,4,6-tcp), a hazardous pollutant, in the aerobic bacterium cupriavidus necator jmp134(pjp4) (formerly ralstonia eutropha jmp134) is encoded by the tcp genes. these genes are located in a genetic context, tcprxabcyd, which resembles a putative catabolic operon. in this work, these gene sequences were individually disrupted and mutant strains were evaluated for their ability to grow on or degrade 2,4,6-tcp. the tcpx and tcpa mutants completely fai ... | 2007 | 17322325 |
| bacterial diversity in mine tailings compared by cultivation and cultivation-independent methods and their resistance to lead and cadmium. | to examine bacterial community composition in rhizosphere of plants colonizing on mine tailings and phylogenetic differences between subcommunities resistant to different metals, we constructed four clone libraries of 16s rdna sequences. one was amplified directly from tailing microbial dna (named as ci library) and three from cultures on the plates containing of 0.5 mm cdcl(2) (cd library), 2 mm pb (no(3))(2) (pb library), and without any metals (cw library). in total, nine bacterial divisions ... | 2007 | 17333426 |
| two host-induced ralstonia solanacearum genes, acra and dinf, encode multidrug efflux pumps and contribute to bacterial wilt virulence. | multidrug efflux pumps (mdrs) are hypothesized to protect pathogenic bacteria from toxic host defense compounds. we created mutations in the ralstonia solanacearum acra and dinf genes, which encode putative mdrs in the broad-host-range plant pathogen. both mutations reduced the ability of r. solanacearum to grow in the presence of various toxic compounds, including antibiotics, phytoalexins, and detergents. both acrab and dinf mutants were significantly less virulent on the tomato plant than the ... | 2007 | 17337552 |
| impairment of cellulose synthases required for arabidopsis secondary cell wall formation enhances disease resistance. | cellulose is synthesized by cellulose synthases (cesas) contained in plasma membrane-localized complexes. in arabidopsis thaliana, three types of cesa subunits (cesa4/irregular xylem5 [irx5], cesa7/irx3, and cesa8/irx1) are required for secondary cell wall formation. we report that mutations in these proteins conferred enhanced resistance to the soil-borne bacterium ralstonia solanacearum and the necrotrophic fungus plectosphaerella cucumerina. by contrast, susceptibility to these pathogens was ... | 2007 | 17351116 |
| occurrence of burkholderia cepacia complex, ralstonia and pandoraea species dnas in the coastal environment of the straits of messina (italy). | 2007 | 17360005 | |
| metabolic and phylogenetic analysis of microbial communities during phytoremediation of soil contaminated with weathered hydrocarbons and heavy metals. | in the current study, the microbial ecology of weathered hydrocarbon and heavy metal contaminated soil undergoing phytoremediation was studied. the relationship of functional diversity, measured as carbon source utilisation in biolog plates and extracellular enzymatic activities, and genetic diversity of bacteria was evaluated. denaturing gradient gel electrophoresis was used for community analyses at the species level. bulk soil and rhizosphere soil from pine and poplar plantations were analyse ... | 2007 | 17372705 |
| spatial distribution and physiological state of bacteria in a sand column experiment during the biodegradation of toluene. | toxic organic contaminants frequently serve as growth substrates for bacteria. however, long-term exposure to the organic contaminants can result in significant stress or "injury" to bacterial cells such that bacteria may lose, either temporarily or permanently, their capacity to degrade a specific toxic organic contaminant. in order to understand the relationship between biodegradability and physiological conditions of bacteria after a prolonged exposure to a contaminant, biomass samples collec ... | 2007 | 17397899 |
| evaluation of somatic hybrids of potato with solanum stenotomum after a long-term in vitro conservation. | somatic hybrids of potato with a cultivated relative, solanum stenotomum also called solanum tuberosum stenotomum group, were evaluated for their physiological and agronomical characteristics as well as the stability of the introgressed resistance to bacterial wilt, caused by ralstonia solanacearum, after a long-term in vitro conservation for more than 5 years. analysis of photosynthesis showed that the pepc/rubisco ratio remained lower than 0.5 for all vitroplants of potato and the somatic hybr ... | 2007 | 17400465 |
| kinetics of microbial bromate reduction in a hydrogen-oxidizing, denitrifying biofilm reactor. | bromate (bro(3)(-)) is an oxidized contaminant produced from bromide (br(-)) during ozonation and advanced oxidation of drinking water. previous research shows that denitrifying bioreactors can reduce bromate to innocuous bromide. we studied a hydrogen-based, denitrifying membrane-biofilm reactor (mbfr) for bromate reduction, and report the first kinetics for a hydrogen-based bromate reduction process. a mixed-culture mbfr reduced up to 1,500 microg/l bromate to below 10 microg/l with a 50-min h ... | 2007 | 17405178 |