| interactions of the fucose-specific pseudomonas aeruginosa lectin, pa-iil, with mammalian glycoconjugates bearing polyvalent lewis(a) and abh blood group glycotopes. | pseudomonas aeruginosa fuc > man specific lectin, pa-iil, is an important microbial agglutinin that might be involved in p. aeruginosa infections in humans. in order to delineate the structures of these lectin receptors, its detailed carbohydrate recognition profile was studied both by microtiter plate biotin/avidin-mediated enzyme-lectin-glycan binding assay (ellsa) and by inhibition of the lectin-glycan interaction. among 40 glycans tested for binding, pa-iil reacted well with all human blood ... | 2006 | 16762477 |
| heterologous expression and localization of gentisate transporter ncg12922 from corynebacterium glutamicum atcc 13032. | ralstonia sp. strain u2 metabolizes naphthalene via gentisate (2,5-dihydroxybenzoate) to central metabolites, but it was found unable to utilize gentisate as growth substrate. a putative gentisate transporter encoded by ncg12922 from corynebacterium glutamicum atcc 13032 was functionally expressed in ralstonia sp. strain u2, converting strain u2 to a gentisate utilizer. after ncg12922 was inserted into plasmid pgfpe with green fluorescence protein gene gfp, the expressed fusion protein ncg12922- ... | 2006 | 16765316 |
| isolation of bacterial antagonists of aspergillus flavus from almonds. | bacteria were isolated from california almond orchard samples to evaluate their potential antifungal activity against aflatoxin-producing aspergillus flavus. fungal populations from the same samples were examined to determine the incidence of aflatoxigenic aspergillus species. antagonistic activities of the isolated bacterial strains were screened against a nonaflatoxigenic nor mutant of a. flavus, which accumulates the pigmented aflatoxin precursor norsolorinic acid (nor) under conditions condu ... | 2006 | 16767519 |
| unusual entropy-driven affinity of chromobacterium violaceum lectin cv-iil toward fucose and mannose. | the purple pigmented bacterium chromobacterium violaceum is a dominant component of tropical soil microbiota that can cause rare but fatal septicaemia in humans. its sequenced genome provides insight into the abundant potential of this organism for biotechnological and pharmaceutical applications and allowed an orf encoding a protein that is 60% identical to the fucose binding lectin (pa-iil) from pseudomonas aeruginosa and the mannose binding lectin (rs-iil) from ralstonia solanacearum to be id ... | 2006 | 16768446 |
| induction of lateral root structure formation on petunia roots: a novel effect of gmi1000 ralstonia solanacearum infection impaired in hrp mutants. | ralstonia solanacearum is a soilborne plant pathogen that invades its host via roots. as in many gram-negative bacterial plant pathogens, the r. solanacearum hrp type iii secretion system is essential for interactions of the bacterium with plants; however, the related mechanisms involved in disease expression are largely unknown. in this work, we examined the effects of infection by r. solanacearum gmi1000 and hrp mutants on the root system of petunia plants. both the wild-type and mutant strain ... | 2006 | 16776293 |
| popf1 and popf2, two proteins secreted by the type iii protein secretion system of ralstonia solanacearum, are translocators belonging to the hrpf/nopx family. | ralstonia solanacearum gmi1000 is a gram-negative plant pathogen which contains an hrp gene cluster which codes for a type iii protein secretion system (ttss). we identified two novel hrp-secreted proteins, called popf1 and popf2, which display similarity to one another and to putative ttss translocators, hrpf and nopx, from xanthomonas spp. and rhizobia, respectively. they also show similarities with ttss translocators of the yopb family from animal-pathogenic bacteria. both popf1 and popf2 bel ... | 2006 | 16788199 |
| identification of a response regulator gene for catabolite control from a pcb-degrading beta-proteobacteria, acidovorax sp. kks102. | acidovorax sp. (formally pseudomonas sp.) strain kks102 carries a bph operon for the degradation of pcb/biphenyl. transcription from the pe promoter for the bph operon was found to be under catabolite control, i.e. the promoter activity was at a lower level when succinate, fumarate or acetate was added to the culture. some mutations in the immediate upstream region of the pe promoter resulted in catabolite-insensitive and constitutively low promoter activity, suggesting that a transcriptional ac ... | 2006 | 16796688 |
| cloning and expression of the gene for periplasmic poly(vinyl alcohol) dehydrogenase from sphingomonas sp. strain 113p3, a novel-type quinohaemoprotein alcohol dehydrogenase. | a gene for periplasmic poly(vinyl alcohol) (pva) dehydrogenase (pvadh) was cloned, based on the n-terminal amino acid sequence of the purified pvadh from sphingomonas sp. 113p3 and the sequence of the gene for pvadh (pvaa, genbank accession no. ab190288). the recombinant pvadh tagged with hexahistidine was expressed in escherichia coli and purified to homogeneity. the recombinant enzyme had the same characteristics as the purified enzyme from sphingomonas sp. strain 113p. in addition to pva, the ... | 2006 | 16804170 |
| proteomic examination of ralstonia eutropha in cellular responses to formic acid. | in this study, ralstonia eutropha was used to elucidate protein changes in response to formic acid. sixty-three differentially expressed proteins in relation to formic acid in r. eutropha were found with 1-d page and nano-lc-ms/ms. among the proteins with decreased expression, four were involved in the shikimate pathway and three proteins in the pyrimidine biosynthesis pathway. with the increased expression of proteins, a dramatic change occurred in the induction of ion transporters in relation ... | 2006 | 16807942 |
| impacts of 2,4-d application on soil microbial community structure and on populations associated with 2,4-d degradation. | the effect of 2,4-dichlorophenoxyacetic acid (2,4-d) application rate on microbial community structure and on the diversity of dominant 2,4-d degrading bacteria in an agricultural soil was examined using cultivation-independent molecular techniques coupled with traditional isolation and enumeration methods. fingerprints of microbial communities established under increasing concentrations of 2,4-d (0-500 mg kg-1) in batch soil microcosms were obtained using denaturing gradient gel electrophoresis ... | 2007 | 16814534 |
| 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 |
| evaluation of pyrrolidonyl arylamidase for the identification of nonfermenting gram-negative rods. | to evaluate the activity of pyrrolidonyl arylamidase (pyr) for the differentiation and identification of nonfermenting gram negative rods (nfgnr), 293 isolates were tested. a 24 h culture of each test organism was prepared. from this a 108-109 cfu/ml suspension was added to 0.25 ml of sterile physiologic solution. a pyr disk was then added and the test was incubated for 30 minutes at 35-37 degrees c, at environmental atmosphere. reading was done by adding 1 drop of cinnamaldehyde reagent. strain ... | 2007 | 16822636 |
| 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 |
| optimal biostimulation strategy for phenol degradation with indigenous rhizobium ralstonia taiwanensis. | this study provides a first attempt from a perspective of gaden's classification of fermentation and phase-plane to put forward phenol degradation using various augmented nutrient media for biostimulation. it aimed to identify the most promising nutrient source(s) to attenuate synergistic interactions with phenol for optimal phenol degradation. therefore, the growth association of phenol degradation using various nutrient media in place of combined toxic interactions was established via gaden's ... | 2007 | 16844294 |
| 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 |
| a novel esterase from ralstonia sp. m1: gene cloning, sequencing, high-level expression and characterization. | a newly isolated gene from ralstonia sp. m1, encoding an esterase, was cloned in escherichia coli and its nucleotide sequence determined. the 1.6kb insert revealed one complete open reading frame, predicted to encode an esterase (320 aa, 34.1kda) with a pi of 9.86. estr contained a putative oxyanion hole h36g37, a conserved pentapeptide g103hslg107 and a conserved catalytic his265 and asp237. the estr sequence shared 64-70 and 44-48% identity with the hydrolases/acyltransferases from burkholderi ... | 2007 | 16893659 |
| 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 |
| the barley erf-type transcription factor hvraf confers enhanced pathogen resistance and salt tolerance in arabidopsis. | we isolated hvraf (hordeum vulgare root abundant factor), a cdna encoding a novel ethylene response factor (erf)-type transcription factor, from young seedlings of barley. in addition to the most highly conserved apetala2/erf dna-binding domain, the encoded protein contained an n-terminal mcggail signature sequence, a putative nuclear localization sequence, and a c-terminal acidic transcription activation domain containing a novel mammalian hemopexin domain signature-like sequence. their homolog ... | 2007 | 16937017 |
| 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 |
| role of eukaryotic microbiota in soil survival and catabolic performance of the 2,4-d herbicide degrading bacteria cupriavidus necator jmp134. | cupriavidus necator (formerly ralstonia eutropha) jmp134, harbouring the catabolic plasmid pjp4, is the best-studied 2,4-dichlorophenoxyacetic acid (2,4-d) herbicide degrading bacterium. a study of the survival and catabolic performance of strain jmp134 in agricultural soil microcosms exposed to high levels of 2,4-d was carried out. when c. necator jmp134 was introduced into soil microcosms, the rate of 2,4-d removal increased only slightly. this correlated with the poor survival of the strain, ... | 2007 | 17043913 |
| 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 |
| 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 |
| characterization of a cyanobacterial-like uptake [nife] hydrogenase: epr and ftir spectroscopic studies of the enzyme from acidithiobacillus ferrooxidans. | electron paramagnetic resonance (epr) and fourier transform ir studies on the soluble hydrogenase from acidithiobacillus ferrooxidans are presented. in addition, detailed sequence analyses of the two subunits of the enzyme have been performed. they show that the enzyme belongs to a group of uptake [nife] hydrogenases typical for cyanobacteria. the sequences have also a close relationship to those of the h(2)-sensor proteins, but clearly differ from those of standard [nife] hydrogenases. it is co ... | 2007 | 17082918 |
| genomic structure and phylogeny of the plant pathogen ralstonia solanacearum inferred from gene distribution analysis. | in the present study, we investigated the gene distribution among strains of the highly polymorphic plant pathogenic beta-proteobacterium ralstonia solanacearum, paying particular attention to the status of known or candidate pathogenicity genes. based on the use of comparative genomic hybridization on a pangenomic microarray for the gmi1000 reference strain, we have defined the conditions that allowed comparison of the repertoires of genes among a collection of 18 strains that are representativ ... | 2007 | 17085551 |
| biodegradation kinetics of the nitramine explosive cl-20 in soil and microbial cultures. | the cyclic nitramine explosive cl-20 (c(6)h(6)n(12)o(12), 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12 -hexaazaisowurtzitane) is a relatively new energetic compound which could be a persistent organic pollutant. to follow its biodegradation dynamics, cl-20 was added to soil alone or together with organic co-substrates and n-source and incubated under oxic and anoxic conditions. without co-substrates, the cl-20 degradation was detectable only under anoxic conditions. the highest degradation rate was fou ... | 2007 | 17091356 |
| 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 |
| expression of a novel small antimicrobial protein from the seeds of motherwort (leonurus japonicus) confers disease resistance in tobacco. | medicinal plants are valuable resources of natural antimicrobial materials. a novel small protein with antimicrobial activities, designated ljamp1, was purified from the seeds of a medicinal herb, motherwort (leonurus japonicus houtt). ljamp1 is a heat-stable protein with a molecular mass of 7.8 kda and a determined isoelectric point of 8.2. in vitro assays showed that ljamp1 inhibits the growth of an array of fungi and bacteria. the hyphal growth inhibition by ljamp1 was more evident against hy ... | 2007 | 17158620 |
| transcriptional activator tsrf1 reversely regulates pathogen resistance and osmotic stress tolerance in tobacco. | increasing evidences show that ethylene-responsive factor (erf) proteins regulate plant stress response and the interaction of different stress responsive pathways through interacting with different cis-acting elements, even other transcription factors. here, we report a transcriptional activator tsrf1, which was previously demonstrated to regulate plant resistance to ralstonia solanacearum, reversely regulates pathogen resistance and osmotic stress tolerance in tobacco. sequence analysis reveal ... | 2007 | 17160455 |
| growth of the genetically engineered strain cupriavidus necator rw112 with chlorobenzoates and technical chlorobiphenyls. | cupriavidus necator (formerly ralstonia eutropha) strain h850 is known to grow on biphenyl, and to co-oxidize congeners of polychlorinated biphenyls (pcbs). using a tn5-based minitransposon shuttle system and the tol plasmid, the rational construction of hybrids of h850 was achieved by subsequent introduction of three distinct elements carrying 11 catabolic loci from three other biodegrading bacteria into the parent strain, finally yielding c. necator rw112. the new genetic elements introduced i ... | 2007 | 17185547 |
| evolutionary dynamics of ralstonia solanacearum. | we investigated the genetic diversity, extent of recombination, natural selection, and population divergence of ralstonia solanacearum samples obtained from sources worldwide. this plant pathogen causes bacterial wilt in many crops and constitutes a serious threat to agricultural production due to its very wide host range and aggressiveness. five housekeeping genes, dispersed around the chromosome, and three virulence-related genes, located on the megaplasmid, were sequenced from 58 strains belo ... | 2007 | 17189443 |
| crystal structure and mechanism of tryptophan 2,3-dioxygenase, a heme enzyme involved in tryptophan catabolism and in quinolinate biosynthesis. | the structure of tryptophan 2,3-dioxygenase (tdo) from ralstonia metallidurans was determined at 2.4 a. tdo catalyzes the irreversible oxidation of l-tryptophan to n-formyl kynurenine, which is the initial step in tryptophan catabolism. tdo is a heme-containing enzyme and is highly specific for its substrate l-tryptophan. the structure is a tetramer with a heme cofactor bound at each active site. the monomeric fold, as well as the heme binding site, is similar to that of the large domain of indo ... | 2007 | 17198384 |
| production of polyhydroxybutyrate in sugarcane. | we report here the production of the bacterial polyester, polyhydroxybutyrate (phb), in the crop species sugarcane (saccharum spp. hybrids). the phb biosynthesis enzymes of ralstonia eutropha [beta-ketothiolase (phaa), acetoacetyl-reductase (phab) and phb synthase (phac)] were expressed in the cytosol or targeted to mitochondria or plastids. phb accumulated in cytosolic lines at trace amounts, but was not detected in mitochondrial lines. in plastidic lines, phb accumulated in leaves to a maximum ... | 2007 | 17207265 |
| desulfurization of aromatic sulfonates by rhizosphere bacteria: high diversity of the asfa gene. | the plant growth-promoting effect of pseudomonas putida s-313 is associated with its ability to desulfurize arylsulfonates. to understand this further, other plant-associated bacteria able to desulfurize a range of arylsulfonates were isolated from the rhizospheres of winter and spring barley. the isolates belonged to the beta-proteobacteria, including bacteria from the variovorax paradoxus group and from the acidovorax genus. they desulfurized toluenesulfonate to p-cresol, and were found to con ... | 2007 | 17222151 |
| impact of alterations near the [nife] active site on the function of the h(2) sensor from ralstonia eutropha. | in proteobacteria capable of h(2) oxidation under (micro)aerobic conditions, hydrogenase gene expression is often controlled in response to the availability of h(2). the h(2)-sensing signal transduction pathway consists of a heterodimeric regulatory [nife]-hydrogenase (rh), a histidine protein kinase and a response regulator. to gain insights into the signal transmission from the ni-fe active site in the rh to the histidine protein kinase, conserved amino acid residues in the l0 motif near the a ... | 2007 | 17222178 |
| redox and functional analysis of the rieske ferredoxin component of the toluene 4-monooxygenase. | toluene 4-monooxygenase catalyzes the nadh- and o2-dependent hydroxylation of toluene to form p-cresol. the four-protein complex consists of a diiron hydroxylase, an oxidoreductase, a catalytic effector protein, and a rieske-type ferredoxin (t4moc). phylogenetic analysis suggests that t4moc is part of a clade specialized for reaction with diiron hydroxylases, possibly reflected in the conservation of w69, whose indole side chain makes close contacts with a bridging sulfide. in order to further i ... | 2007 | 17240981 |
| pathogen-induced calmodulin isoforms in basal resistance against bacterial and fungal pathogens in tobacco. | thirteen tobacco calmodulin (cam) genes fall into three distinct amino acid homology types. wound-inducible type i isoforms ntcam1 and 2 were moderately induced by tobacco mosaic virus (tmv)-mediated hypersensitive reaction, and the type iii isoform ntcam13 was highly induced, while the type ii isoforms ntcam3-ntcam12 showed little response. type i and iii knockdown tobacco lines were generated using inverted repeat sequences from ntcam1 and 13, respectively, to evaluate the contribution of path ... | 2007 | 17251204 |
| heat-shock protein hspa mimics the function of phasins sensu stricto in recombinant strains of escherichia coli accumulating polythioesters or polyhydroxyalkanoates. | polyhydroxyalkanoic acids (phas) are synthesized by unspecific pha synthases and deposited as energy and carbon storage granules in the cytoplasm of many prokaryotes. the number and size of the granules depend on the presence of phasins which are amphiphilic structural proteins occurring at the granule surface. recently, it was shown that polythioesters (ptes) are also synthesized by pha synthases. to increase the yield of these polymers, the role of recombinant phasins was analysed in an artifi ... | 2007 | 17259608 |
| sequencing microbial copolymers of 3-hydroxybutyric and 3-mercaptoalkanoic acids by nmr, electrospray ionization mass spectrometry, and size exclusion chromatography nmr. | copolymers of 3-hydroxybutyrate (3hb) and 3-mercaptopropionate (3mp) or 3-mercaptobutyrate (3mb) units and minor amounts of 3-hydroxypropionate (3hp), 3-hydroxyvalerate (3hv), or 3-mercaptovalerate (3mv) were investigated regarding their microstructure by nmr, electrospray ionization mass spectrometry, and size exclusion chromatography nmr. these copolymers were produced by ralstonia eutropha strain h16 when cells were cultivated in a mineral salts medium with gluconate as a carbon source for gr ... | 2007 | 17261066 |
| erythromycin resistance-conferring plasmid prsb105, isolated from a sewage treatment plant, harbors a new macrolide resistance determinant, an integron-containing tn402-like element, and a large region of unknown function. | the erythromycin resistance plasmid prsb105 was previously isolated from an activated sludge bacterial community of a municipal wastewater treatment plant. compilation of the complete prsb105 nucleotide sequence revealed that the plasmid is 57,137 bp in size and has a mean g+c content of 56.66 mol%. the prsb105 backbone is composed of two different replication and/or partitioning modules and a functional mobilization region encoding the mobilization genes mobcde and mobba. the first replicon (re ... | 2007 | 17261525 |
| identification of diazotrophs in the culturable bacterial community associated with roots of lasiurus sindicus, a perennial grass of thar desert, india. | lasiurus sindicus is a highly nutritive, drought-tolerant, perennial grass that is endemic to the thar desert of rajasthan, india. analysis of 16s rrna coding genes of the bacterial isolates enriched in nitrogen-free semisolid medium, from the surface-sterilized roots of l. sindicus, showed predominance of gram-negative over gram-positive bacteria. according to comparative sequence analysis of 16s rdna sequence data, gram-positive bacteria with low gc content (staphylococcus warneri and bacillus ... | 2007 | 17264993 |
| 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 |
| heavy metal resistance and genotypic analysis of metal resistance genes in gram-positive and gram-negative bacteria present in ni-rich serpentine soil and in the rhizosphere of alyssum murale. | forty-six bacterial cultures, including one culture collection strain, thirty from the rhizosphere of alyssum murale and fifteen from ni-rich soil, were tested for their ability to tolerate arsenate, cadmium, chromium, zinc, mercury, lead, cobalt, copper, and nickel in their growth medium. the resistance patterns, expressed as minimum inhibitory concentrations, for all cultures to the nine different metal ions were surveyed by using the agar dilution method. a large number of the cultures were r ... | 2007 | 17276484 |
| characterization of the signaling domain of the no-responsive regulator norr from ralstonia eutropha h16 by site-directed mutagenesis. | in ralstonia eutropha h16, the nitric oxide (no)-responsive transcriptional activator norr controls the expression of a dicistronic operon that encodes a membrane-bound no reductase, norb, and a protein of unknown function, nora. the n-terminal domain (ntd) of norr is responsible for perception of the signal molecule, nitric oxide. thirteen out of 29 conserved residues of the ntd were exchanged by site-directed mutagenesis. replacement of r63, r72, d93, d96, c112, d130, or f137 strongly decrease ... | 2007 | 17277050 |
| studies on the influence of phasins on accumulation and degradation of phb and nanostructure of phb granules in ralstonia eutropha h16. | phasins play an important role in the formation of poly(3-hydroxybutyrate) [phb] granules and affect their size and number in the cells. recent studies on the phb granule proteome and analysis of the complete genomic dna sequence of ralstonia eutropha h16 have identified three homologues of the phasin protein phap1. in this study, mutants of r. eutropha deficient in the expression of the phasin genes phap1, phap2, phap3, phap4, phap12, phap123, and phap1234 were examined by gas chromatography. i ... | 2007 | 17291089 |
| poly[(r)-3-hydroxybutyrate] formation in escherichia coli from glucose through an enoyl-coa hydratase-mediated pathway. | in this study, a new metabolic pathway for the synthesis of poly[(r)-3-hydroxybutyrate] [p(3hb)] was constructed in a recombinant escherichia coli strain that utilized forward and reverse reactions catalyzed by two substrate-specific enoyl-coa hydratases, r-hydratase (phaj) and s-hydratase (fadb), to epimerize (s)-3hb-coa to (r)-3hb-coa via a crotonyl-coa intermediate. the r-hydratase gene (phaj(ac)) from aeromonas caviae was coexpressed with the pha synthase gene (phac(re)) and 3-ketothiolase g ... | 2007 | 17298899 |
| [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 |
| 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 |
| semicontinuous microcosm study of aerobic cometabolism of trichloroethylene using toluene. | a semicontinuous slurry-microcosm method was applied to mimic trichloroethylene (tce) cometabolic biodegradation field results at the que-jen in-situ pilot study. the microcosm study confirmed the process of aerobic cometabolism of tce using toluene as the primary substrate. based on the nucleotide sequence of 16s rrna genes, the toluene-oxidizing bacteria in microcosms were identified, i.e. ralstonia sp. p-10 and pseudomonasputida. the first-order constant of tce-degradation rate was 0.5 day(-1 ... | 2007 | 17412499 |
| [high speed separation and quantitation of ralstonia solanacearum of different virulence using high performance ion exchange chromatography]. | high performance ion exchange chromatography coupled with laser light scattering instrument was employed for the rapid separation and quantitation of ralstonia solanacearum of different virulence. the pure culture of ralstonia solanacearum was successfully separated into three characteristic fractions. each fraction was collected and inoculated onto 2,3,5-triphenyltetrazolium chloride (ttc) plates to identify its virulence. the shapes and colors of the colonies were imaged, and the average atten ... | 2007 | 17432579 |
| [screening and identification of a photosynthetic bacterium reducing selenite to red elemental selenium]. | selenium is essential element for humans and animals but is very toxic at higher concentrations. in four inorganic states of selenate [seo4 2- ( vi)], selenite [seo3 2- (iv)], elemental selenium [se (0)] and selenide [se2- (- ii )], selenite is well known to be more soluble and higher toxic than other three forms. many microorganisms have the capacity to reduce selenite to red elemental selenium, which provide the potential to cope with the detoxification of pollution and to use the biological a ... | 2007 | 17436622 |
| [characterization of ralstonia solanacearum in different growth phases by high performance ion exchange liquid chromatography analysis]. | high performance ion exchange liquid chromatography and laser light scattering instrument were employed to characterize ralstonia solanacearum in different growth phases. the pure culture of ralstonia solanacearum was successfully separated into three characteristic fractions. chromatographic behaviors of ralstonia solanacearum in lag phase, logarithmic phase and stationary phase were carefully investigated, and their relationships to the cell concentration, ph of fermentation broth and extracel ... | 2007 | 17436642 |
| kinetic studies on autohydrogenotrophic growth of ralstonia eutropha with nitrate as terminal electron acceptor. | autohydrogenotrophic batch growth of ralstonia eutropha h16 was studied in a stirred-tank reactor with nitrate and nitrite as terminal electron acceptors and the sole limiting substrates. assuming product inhibition by nitrite, saturation kinetics with the two limiting substrates and a simple switching function, which allows growth on nitrite only at low nitrate concentrations, resulted in a kinetic growth model with nine model parameters. the data of two batch experiments were used to identify ... | 2007 | 17457540 |
| repeat domain diversity of avrbs3-like genes in ralstonia solanacearum strains and association with host preferences in the field. | genes homologous to avrbs3 of xanthomonas were detected in 309 strains of ralstonia solanacearum biovars 3, 4, and 5 but not biovar 1 or 2. a statistically significant association between the originating plant species and internal repeats of the gene was found. sequences of repeats and variation between nearly clonal strains revealed evidence of frequent recombination. | 2007 | 17468277 |
| using the ralstonia solanacearum tat secretome to identify bacterial wilt virulence factors. | to identify secreted virulence factors involved in bacterial wilt disease caused by the phytopathogen ralstonia solanacearum, we mutated tatc, a key component of the twin-arginine translocation (tat) secretion system. the r. solanacearum tatc mutation was pleiotropic; its phenotypes included defects in cell division, nitrate utilization, polygalacturonase activity, membrane stability, and growth in plant tissue. bioinformatic analysis of the r. solanacearum strain gmi1000 genome predicted that t ... | 2007 | 17468289 |
| formation of a dinitrosyl iron complex by nora, a nitric oxide-binding di-iron protein from ralstonia eutropha h16. | in ralstonia eutropha h16, two genes, nora and norb, form a dicistronic operon that is controlled by the no-responsive transcriptional regulator norr. norb has been identified as a membrane-bound no reductase, but the physiological function of nora is unknown. we found that, in a nora deletion mutant, the promoter activity of the norab operon was increased 3-fold, indicating that nora attenuates activation of norr. nora shows limited sequence similarity to the oxygen carrier hemerythrin, which c ... | 2007 | 17507380 |
| characterization of multiple novel aerobic polychlorinated biphenyl (pcb)-utilizing bacterial strains indigenous to contaminated tropical african soils. | contaminated sites in lagos, nigeria were screened for the presence of chlorobiphenyl-degrading bacteria. the technique of continual enrichment on askarel fluid yielded bacterial isolates able to utilize dichlorobiphenyls (dicbs) as growth substrates and six were selected for further studies. phenotypic typing and 16s rdna analysis classified these organisms as species of enterobacter, ralstonia and pseudomonas. all the strains readily utilized a broad spectrum of xenobiotics as sole sources of ... | 2008 | 17534725 |
| engineering of pa-iil lectin from pseudomonas aeruginosa - unravelling the role of the specificity loop for sugar preference. | lectins are proteins of non-immune origin capable of binding saccharide structures with high specificity and affinity. considering the high encoding capacity of oligosaccharides, this makes lectins important for adhesion and recognition. the present study is devoted to the pa-iil lectin from pseudomonas aeruginosa, an opportunistic human pathogen capable of causing lethal complications in cystic fibrosis patients. the lectin may play an important role in the process of virulence, recognizing spe ... | 2007 | 17540045 |
| variation in copolymer composition and molecular weight of polyhydroxyalkanoate generated by saturation mutagenesis of aeromonas caviae pha synthase. | amino acid substitutions at two residues downstream from the active-site histidine of polyhydroxyalkanoate (pha) synthases are effective for changing the composition and the molecular weight of pha. in this study, saturation mutagenesis at the position ala505 was applied to pha synthase (phacac) from aeromonas caviae to investigate the effects on the composition and the molecular weight of pha synthesized in ralstonia eutropha. the copolymer composition and molecular weight of pha were varied by ... | 2007 | 17541931 |
| toward automated analysis of biofilm architecture: bias caused by extraneous confocal laser scanning microscopy images. | an increasing number of studies utilize confocal laser scanning microscopy (clsm) for in situ visualization of biofilms and rely on the use of image analysis programs to extract quantitative descriptors of architecture. recently, designed programs have begun incorporating procedures to automatically determine threshold values for three-dimensional clsm image stacks. we have found that the automated threshold calculation is biased when a stack contains images lacking pixels of biological signific ... | 2007 | 17545329 |
| a national outbreak of ralstonia mannitolilytica associated with use of a contaminated oxygen-delivery device among pediatric patients. | in august 2005, the centers for disease control and prevention was notified of a ralstonia species outbreak among pediatric patients receiving supplemental oxygen therapy with the vapotherm 2000i (vapotherm, inc, stevensville, md). the vapotherm 2000i is a reusable medical device that was used in >900 hospitals in the united states in 2005. ralstonia are waterborne bacilli that have been implicated in hospital-acquired infections. we initiated an investigation to determine the source of the outb ... | 2007 | 17545371 |
| providing a safety net for children: investigating a multistate outbreak of ralstonia mannitolilytica related to a contaminated reusable device. | | 2007 | 17545391 |
| adsorption and hydrolysis reactions of poly(hydroxybutyric acid) depolymerases secreted from ralstonia pickettii t1 and penicillium funiculosum onto poly[(r)-3-hydroxybutyric acid]. | reaction processes of poly[(r)-3-hydroxybutyric acid] (p(3hb)) with two types of poly(hydroxybutyric acid) (phb) depolymerases secreted from ralstonia pickettii t1 and penicillium funiculosum were characterized by means of atomic force microscopy (afm) and quartz crystal microbalance (qcm). the phb depolymerase from r. pickettii t1 consists of catalytic, linker, and substrate-binding domains, whereas the one from p. funiculosum lacks a substrate-binding domain. we succeeded in observing the adso ... | 2007 | 17547455 |
| [isolation, identification and field control efficacy of an endophytic strain against tobacco bacterial wilt (ralstonia solanacarum)]. | in this paper, an endophytic strain b-001 against tobacco bacterial wilt (ralstonia solanacarum) was isolated from the stem of healthy tobacco in r. solanacarum-infected fields, which had a stronger inhibitory effect on some kinds of gram-positive bacteria, gram-negative bacteria, and pathogenic fungi. this strain belonged to bacillus, and its 16s rdna after pcr and sequencing had an accession of genbank being dq444283. the 16s rdna phylogenetic tree was constructed with mega3, and compared with ... | 2007 | 17552192 |