| the arabidopsis thaliana dna-binding protein ahl19 mediates verticillium wilt resistance. | verticillium spp. are destructive soilborne fungal pathogens that cause vascular wilt diseases in a wide range of plant species. verticillium wilts are particularly notorious, and genetic resistance in crop plants is the most favorable means of disease control. in a gain-of-function screen using an activation-tagged arabidopsis mutant collection, we identified four mutants, a1 to a4, which displayed enhanced resistance toward the vascular wilt species verticillium dahliae, v. albo-atrum and v. l ... | 2011 | 21864046 |
| The crystal structure of an oxygen-tolerant hydrogenase uncovers a novel iron-sulphur centre. | Hydrogenases are abundant enzymes that catalyse the reversible interconversion of H(2) into protons and electrons at high rates. Those hydrogenases maintaining their activity in the presence of O(2) are considered to be central to H(2)-based technologies, such as enzymatic fuel cells and for light-driven H(2) production. Despite comprehensive genetic, biochemical, electrochemical and spectroscopic investigations, the molecular background allowing a structural interpretation of how the catalytic ... | 2011 | 22002606 |
| Comparative and functional genomics of Rhodococcus opacus PD630 for biofuels development. | The Actinomycetales bacteria Rhodococcus opacus PD630 and Rhodococcus jostii RHA1 bioconvert a diverse range of organic substrates through lipid biosynthesis into large quantities of energy-rich triacylglycerols (TAGs). To describe the genetic basis of the Rhodococcus oleaginous metabolism, we sequenced and performed comparative analysis of the 9.27 Mb R. opacus PD630 genome. Metabolic-reconstruction assigned 2017 enzymatic reactions to the 8632 R. opacus PD630 genes we identified. Of these, 261 ... | 2011 | 21931557 |
| Functional diversification of the GALA type III effector family contributes to Ralstonia solanacearum adaptation on different plant hosts. | Type III effectors from phytopathogenic bacteria exhibit a high degree of functional redundancy, hampering the evaluation of their precise contribution to pathogenicity. This is illustrated by the GALA type III effectors from Ralstonia solanacearum, which have been shown to be collectively, but not individually, required for disease on Arabidopsis thaliana and tomato. We investigated evolution, redundancy and diversification of this family in order to understand the individual contribution of th ... | 2011 | 21902695 |
| characterization of biofumigated ralstonia solanacearum cells using micro-raman spectroscopy and electron microscopy. | essential oils of palmarosa, lemongrass, and eucalyptus have shown promise as biofumigants for control of the bacterial wilt disease of edible ginger (zingiber officinale) caused by ralstonia solanacearum race 4 in previous potting medium studies. biochemical changes in r. solanacearum cells were evaluated with micro-raman spectroscopy following treatment with essential oils at different concentrations (0.04, 0.07, and 0.14% [vol/vol] of culture medium) and changes in cell structure were observe ... | 2012 | 21899389 |
| glygly-cterm and rhombosortase: a c-terminal protein processing signal in a many-to-one pairing with a rhomboid family intramembrane serine protease. | the rhomboid family of serine proteases occurs in all domains of life. its members contain at least six hydrophobic membrane-spanning helices, with an active site serine located deep within the hydrophobic interior of the plasma membrane. the model member glpg from escherichia coli is heavily studied through engineered mutant forms, varied model substrates, and multiple x-ray crystal studies, yet its relationship to endogenous substrates is not well understood. here we describe an apparent membr ... | 2011 | 22194940 |
| ralstonia mannitolilytica and copd: a case report. | | 2011 | 22130767 |
| Immobilization of organophosphohydrolase OpdA from Agrobacterium radiobacter by overproduction at the surface of polyester inclusions inside engineered Escherichia coli. | Organophosphorus pesticides (OP) are highly toxic and are widely used as insecticides. Bacterial organophosphohydrolases which hydrolyse a variety of OPs have been considered for the clean-up of polluted environments. This study describes the engineering of Escherichia coli towards the overproduction of the organophosphohydrolase (OpdA) from A. radiobacter at the surface of polyester inclusions. The OpdA was N-terminally fused via a designed linker region to the C-terminus of polyester inclusion ... | 2011 | 22170266 |
| Cupriavidus and Burkholderia species associated with agricultural plants that grow in alkaline soils. | The presence of Burkholderia, Cupriavidus, and Ralstonia species in northeastern Mexico was investigated. An analysis of the root surrounding soil from different agricultural plants led to the isolation of Burkholderia and Cupriavidus species but no Ralstonia strains. Most Cupriavidus species were unknown and grouped into two clusters according to ARDRA profiles. The 16S rRNA sequence analysis showed that the Cupriavidus isolates were highly related among them and with different Cupriavidus spec ... | 2011 | 22203548 |
| Coupling of permeabilized cells of Gluconobacter oxydans and Ralstonia eutropha for asymmetric ketone reduction using H(2) as reductant. | A combined two-cell reaction system containing Gluconobacter oxydans and Ralstonia eutropha was evaluated with regard to asymmetric ketone reduction using H(2) as the reductant. Whole cells permeabilized by EDTA/toluene were used, and synthesis was performed in a biphasic aqueous/organic reaction medium. The two-cell system was compared with a system in which G. oxydans alone was used for both ketone reduction and cofactor regeneration, using an alcohol as co-substrate. The two-cell system exhib ... | 2012 | 22001848 |
| Implications of various phosphoenolpyruvate-carbohydrate phosphotransferase system mutations on glycerol utilization and poly(3-hydroxybutyrate) accumulation in Ralstonia eutropha H16. | ABSTRACT: The enhanced global biodiesel production is also yielding increased quantities of glycerol as main coproduct. An effective application of glycerol, for example, as low-cost substrate for microbial growth in industrial fermentation processes to specific products will reduce the production costs for biodiesel. Our study focuses on the utilization of glycerol as a cheap carbon source during cultivation of the thermoplastic producing bacterium Ralstonia eutropha H16, and on the investigati ... | 2011 | 21906371 |
| growth and localization of polyhydroxybutyrate granules in ralstonia eutropha. | the bacterium ralstonia eutropha forms cytoplasmic granules of polyhydroxybutyrate that are a source of biodegradable thermoplastic. while much is known about the biochemistry of polyhydroxybutyrate production, the cell biology of granule formation and growth remain unclear. previous studies have suggested that granules form either in the inner membrane, on a central scaffold, or in the cytoplasm. here we used electron cryo-tomography to monitor granule genesis and development in 3-d in a near-n ... | 2011 | 22178974 |
| Isolation and characterization of a soluble and thermostable phosphite dehydrogenase from Ralstonia sp. strain 4506. | Phosphite dehydrogenase (PtxD), which catalyzes the nearly irreversible oxidation of phosphite to phosphate with the concomitant reduction of NAD(+) to NADH, has great potential for NADH regeneration in industrial biocatalysts. Here, we isolated a soil bacterium, Ralstonia sp. strain 4506, that grew at 45°C on a minimal medium containing phosphite as the sole source of phosphorus. A recombinant PtxD of Ralstonia sp. (PtxD(R4506)) appeared in the soluble fraction in Escherichia coli. The purified ... | 2011 | 22197497 |
| role of the hoxz subunit in the electron transfer pathway of the membrane-bound [nife]-hydrogenase from ralstonia eutropha immobilized on electrodes. | the role of the diheme cytochrome b (hoxz) subunit in the electron transfer pathway of the membrane-bound [nife]-hydrogenase (mbh) hetero-trimer from ralstonia eutropha h16 has been investigated. the mbh in its native hetero-trimeric state was immobilized on electrodes and subjected to spectroscopic and electrochemical analysis. surface enhanced resonance raman spectroscopy was used to monitor the redox and coordination state of the hoxz heme cofactors while concomitant protein film voltammetric ... | 2011 | 21761881 |
| biodegradation of tributyl phosphate by novel bacteria isolated from enrichment cultures. | tributyl phosphate (tbp) is an organophosphorous compound, used extensively (3000-5000 tonnes/annum) as a solvent for nuclear fuel processing and as a base stock in the formulation of fire-resistant aircraft hydraulic fluids and other applications. because of its wide applications and relative stability in the natural environment tbp poses the problem of pollution and health hazards. in the present study, fifteen potent bacterial strains capable of using tributyl phosphate (tbp) as sole carbon a ... | 2011 | 21755325 |
| isolation and characterization of a novel virulent podovirus which infects burkholderia pseudomallei. | abstract: burkholderia pseudomallei is a saprophytic soil bacterium and the etiological agent that causes melioidosis. it is naturally resistant to many antibiotics and therefore is difficult to treat. bacteriophages may provide an alternative source of treatment. we have isolated and characterised the bacteriophage phi bp-amp1. the phage is a member of the podoviridae family and has a genome size of ~ 45 kb. molecular data based on the gene which encodes for the phage tail tubular protein sugge ... | 2011 | 21791081 |
| ralstonia solanacearum needs flp pili for virulence on potato. | type iv pili are virulence factors in various bacteria. several subclasses of type iv pili have been described according to the characteristics of the structural prepilin subunit. although type iva pili have been implicated in the virulence of ralstonia solanacearum, type ivb pili have not previously been described in this plant pathogen. here, we report the characterization of two distinct tad loci in the r. solanacearum genome. the tad genes encode functions necessary for biogenesis of the ... | 2011 | 22168446 |
| detection and functional characterization of a large genomic deletion resulting in decreased pathogenicity in ralstonia solanacearum race 3 biovar 2 strains. | bacterial wilt (brown rot) disease of potato caused by ralstonia solanacearum is one of the most important bacterial diseases and a major constraint on potato production worldwide. through a comparative genomic analysis between r. solanacearum'race 3 biovar 2' (r3bv2) strains, we identified a 77 kb region in strain uw551 which is specifically absent in the hypoaggressive strain ipo1609. we proved that ipo1609 indeed carries a 77 kb genomic deletion and provide genetic evidence that occurrence of ... | 2011 | 22050636 |
| structure and molecular evolution of cdgsh iron-sulfur domains. | the recently discovered cdgsh iron-sulfur domains (cisds) are classified into seven major types with a wide distribution throughout the three domains of life. the type 1 protein mitoneet has been shown to fold into a dimer with the signature cdgsh motif binding to a [2fe-2s] cluster. however, the structures of all other types of cisds were unknown. here we report the crystal structures of type 3, 4, and 6 cisds determined at 1.5 å, 1.8 å and 1.15 å resolution, respectively. the type 3 and 4 cisd ... | 2011 | 21949752 |
| antibacterial activity of the flavonoids from dalbergia odorifera on ralstonia solanacearum. | phytohemical investigation on the heartwood of dalbergia odorifera resulted in the isolation of nine flavonoids. their structures were elucidated as sativanone (1), (3r)-vestitone (2), (3r)-2',3',7-trihydroxy-4'-methoxyisoflavanone (3), (3r)-4'-methoxy-2',3,7-trihydroxyisoflavanone (4), carthamidin (5), liquiritigenin (6), isoliquiritigenin (7), (3r)-vestitol (8), and sulfuretin (9) based on their spectral data. all compounds were evaluated for their inhibitory activity against ralstonia solanac ... | 2011 | 22117168 |
| a chromosomal insertion toolbox for promoter probing, mutant complementation and pathogenicity studies in ralstonia solanacearum. | we describe here the construction of a delivery system for stable and directed insertion of gene constructs in a permissive chromosomal site of the bacterial wilt pathogen ralstonia solanacearum. the system consists of a collection of suicide vectors -the prc series- that carry an integration element flanked by transcription terminators and two sequences of homology to the chromosome of strain gmi1000, where the integration element is inserted through a double recombination event. unique restric ... | 2011 | 22122329 |
| ralstonia syzygii, the blood disease bacterium and some asian r. solanacearum strains form a single genomic species despite divergent lifestyles. | the ralstonia solanacearum species complex includes r. solanacearum, r. syzygii, and the blood disease bacterium (bdb). all colonize plant xylem vessels and cause wilt diseases, but with significant biological differences. r. solanacearum is a soilborne bacterium that infects the roots of a broad range of plants. r. syzygii causes sumatra disease of clove trees and is actively transmitted by cercopoid insects. bdb is also pathogenic to a single host, banana, and is transmitted by pollinating ins ... | 2011 | 21931687 |
| ralstonia sp. u2 naphthalene dioxygenase and comamonas sp. js765 nitrobenzene dioxygenase show differences in activity towards methylated naphthalenes. | methylsubstituted naphthalenes constitute a significant part of light gas oil fractions (lgo). these are toxic compounds with low fuel value, and can potentially be enzymatically modified to increase the fuel value and at the same time reduce toxicity. the first step in the biodegradation of naphthalene involves dioxygenation of the aromatic ring catalysed by naphthalene dioxygenase (ndo). here we show that recombinantly produced ndo from ralstonia sp. u2 and the related nitrobenzene dioxygenase ... | 2011 | 22036075 |
| characterization and functional analyses of r-specific enoyl coenzyme a hydratases in polyhydroxyalkanoate-producing ralstonia eutropha. | a genome survey of polyhydroxyalkanoate (pha)-producing ralstonia eutropha h16 detected the presence of 16 orthologs of r-specific enoyl coenzyme a (enoyl-coa) hydratase, among which three proteins shared high homologies with the enzyme specific to enoyl-coas of medium chain length encoded by phaj4 from pseudomonas aeruginosa (phaj4(pa)). the recombinant forms of the three proteins, termed phaj4a(re) to phaj4c(re), actually showed enoyl-coa hydratase activity with r specificity, and the catalyti ... | 2012 | 22081565 |
| the fucose-binding lectin from opportunistic pathogen burkholderia ambifaria binds to both plant and human oligosaccharidic epitopes. | burkholderia ambifaria is generally associated with the rhizosphere of plants where it has biocontrol effects on other microorganisms. it is also a member of the burkhoderia cepacia complex, a group of closely related bacteria that causes lung infections in immunocompromised patients, as well as patients with granulomatous disease or cystic fibrosis. our previous work indicated that fucose on human epithelia is a frequent target for lectins and adhesins of lung pathogens (sulak et al., plos path ... | 2011 | 22170069 |
| identification of mutation points in cupriavidus necator ncimb 11599 and genetic reconstitution of glucose-utilization ability in wild strain h16 for polyhydroxyalkanoate production. | although the facultative chemolithoautotrophic cupriavidus necator (formerly ralstonia eutropha) wild strain h16 is potentially useful as a host for metabolic engineering aimed at polyhydroxyalkanoate production, this organism is deficient in assimilating glucose, a major sugar in non-edible cellulosic resources. growth properties of c. necator h16 harboring heterologous glf (encoding glucose-facilitated diffusion transporter) and glk (encoding glucokinase) from zymomonas mobilis strongly sugges ... | 2011 | 22014784 |
| identification of a multifunctional protein, pham, that determines number, surface to volume ratio, subcellular localization and distribution to daughter cells of poly(3-hydroxybutyrate), phb, granules in ralstonia eutropha h16. | a two-hybrid approach was applied to screen for proteins with the ability to interact with phb synthase (phac1) of ralstonia eutropha. the h16_a0141 gene (pham) was identified in the majority of positive clones. pham (26.6 kda) strongly interacted with phac1 and with phasin phap5 but not with phap1 or other phb granule-associated proteins. a δpham mutant accumulated only one or two large phb granules instead of three to six medium-sized phb granules of the wild type, and distribution of granules ... | 2011 | 22023320 |
| 2,4,5-trichlorophenol degradation using a novel tio2-coated biofilm carrier: roles of adsorption, photocatalysis, and biodegradation. | intimate coupling of photocatalysis and biodegradation (icpb) offers potential for degrading biorecalcitrant and toxic organic compounds. this study reports on a novel sponge-type, tio(2)-coated biofilm carrier that showed significant adherence of tio(2) and ability to accumulate biomass in its interior. this carrier was tested for icpb in a continuous-flow photocatalytic circulating-bed biofilm reactor (pcbbr) to mineralize 2,4,5-trichlorophenol (tcp), which is biorecalcitrant. four mechanisms ... | 2011 | 21861477 |
| inhibition of tobacco bacterial wilt with sulfone derivatives containing an 1,3,4-oxadiazole moiety. | a series of new sulfone compounds containing the 1,3,4-oxadiazole moiety were designed and synthesized. their structures were identified by (1)h and (13)c nuclear magnetic resonance and elemental analyses. antibacterial bioassays indicated that most compounds exhibited promising in vitro antibacterial bioactivities against tobacco bacterial wilt at 200 μg/ml. the relationship between structure and antibacterial activity was also discussed. among the title compounds, 5'c, 5'h, 5'i, and 5'j could ... | 2011 | 22208183 |
| nad(h)-coupled hydrogen cycling - structure-function relationships of bidirectional [nife] hydrogenases. | hydrogenases catalyze the activation or production of molecular hydrogen. due to their potential importance for future biotechnological applications, these enzymes have been in the focus of intense research for the past decades. bidirectional [nife] hydrogenases are of particular interest as they couple the reversible cleavage of hydrogen to the redox conversion of nad(h). in this account, we review the current state of knowledge about mechanistic aspects and structural determinants of these com ... | 2011 | 22056977 |
| catalytic properties of the isolated diaphorase fragment of the nad-reducing [nife]-hydrogenase from ralstonia eutropha. | the nad+-reducing soluble hydrogenase (sh) from ralstonia eutropha h16 catalyzes the h₂-driven reduction of nad+, as well as reverse electron transfer from nadh to h+, in the presence of o₂. it comprises six subunits, hoxhyfui₂, and incorporates a [nife] h+/h₂ cycling catalytic centre, two non-covalently bound flavin mononucleotide (fmn) groups and an iron-sulfur cluster relay for electron transfer. this study provides the first characterization of the diaphorase sub-complex made up of hoxf and ... | 2011 | 22016788 |
| lc-ms/ms quantification of short-chain acyl-coa's in escherichia coli demonstrates versatile propionyl-coa synthetase substrate specificity. | aims: this paper utilized quantitative lc-ms/ms to profile the short-chain acyl-coa levels of several strains of escherichia coli engineered for heterologous polyketide production. to further compare and potentially expand the levels of available acyl-coa molecules, a propionyl-coa synthetase gene from ralstonia solanacearum (prpe-rs) was synthesized and expressed in the engineered strain bap1. methods and results: upon feeding propionate, the engineered e. coli strains had increased the level ... | 2011 | 22118660 |
| the filamentous phage φrss1 enhances virulence of phytopathogenic ralstonia solanacearum on tomato. | ralstonia solanacearum is the causative agent of bacterial wilt in many important crops. φrss1 is a filamentous phage that infects r. solanacearum strains. upon infection, it alters the physiological state and the behavior of host cells. here, we show that r. solanacearum infected by φrss1 becomes more virulent on host plants. some virulence and pathogenicity factors, such as extracellular polysaccharide (eps) synthesis and twitching motility, increased in the bacterial host cells infected with ... | 2011 | 22085298 |
| comparative genomics and functional analysis of the niap family uncover nicotinate transporters from bacteria, plants, and mammals. | the transporter(s) that mediate uptake of nicotinate and its n-methyl derivative trigonelline are not known in plants, and certain mammalian nicotinate transporters also remain unidentified. potential candidates for these missing transporters include proteins from the ubiquitous niap family. in bacteria, niap genes often belong to nad-related regulons, and genetic evidence supports a role for bacillus subtilis and acinetobacter baumannii niap proteins in uptake of nicotinate or nicotinamide. oth ... | 2011 | 21953179 |
| Intermittent trickling bed filter for the removal of methyl ethyl ketone and methyl isobutyl ketone. | Biodegradations of methyl ethyl ketone and methyl isobutyl ketone were performed in intermittent biotrickling filter beds (ITBF) operated at two different trickling periods: 12 h/day (ITBF-12) and 30 min/day (ITBF-0.5). Ralstonia sp. MG1 was able to degrade both ketones as evidenced by growth kinetic experiments. Results show that trickling period is an important parameter to achieve high removal performance and to maintain the robustness of Ralstonia sp. MG1. Overall, ITBF-12 outperformed ITBF- ... | 2011 | 21959582 |
| biosynthesis and characterization of polyhydroxyalkanoate block copolymer p3hb-b-p4hb. | polyhydroxyalkanoates (pha) synthesis genes phbc and orfz cloned from ralstonia eutropha h16 were transformed into beta-oxidation weakened pseudomonas putida ktoy08δgc, a mutant of p. putida kt2442. the recombinant p. putida strain termed kthh06 was able to produce a short-chain-length pha block copolymer consisting of poly(3-hydroxybutyrate) (p3hb) as one block and poly(4-hydroxybutyrate) (p4hb) as another block. one-dimensional and two-dimensional nuclear magnetic resonance (nmr) clearly indic ... | 2011 | 21863836 |
| production of polyhydroxyalkanoates from waste frying oil by cupriavidus necator. | abstract: polyhydroxyalkanoates (phas) are biopolymers, which can replace petrochemical plastics in many applications. however, these bioplastics are currently far more expensive than petrochemical plastics. many researchers are investigating the use of inexpensive substrates derived from waste streams. waste frying oil is abundant and can be used in pha production without filtration.cupriavidus necator (formerly known as ralstonia eutropha) is a versatile organism for the production of phas. sm ... | 2011 | 21906352 |
| genome sequence of the tobacco bacterial wilt pathogen ralstonia solanacearum. | ralstonia solanacearum is a causal agent of plant bacterial wilt with thousands of distinct strains in a heterogeneous species complex. here we report the genome sequence of a phylotype ib strain, y45, isolated from tobacco (nicotiana tabacum) in china. compared with the published genomes of eight strains which were isolated from other hosts and habitats, 794 specific genes and many rearrangements/inversion events were identified in the tobacco strain, demonstrating that this strain represents a ... | 2011 | 21994922 |
| role of hoxe subunit in synechocystis pcc6803 hydrogenase. | cyanobacterial nad(p)(+)-reducing reversible hydrogenases comprise five subunits. four of them (hoxf, hoxu, hoxy, and hoxh) are also found in the well-described related enzyme from ralstonia eutropha. the fifth one (hoxe) is not encoded in the r. eutropha genome, but shares homology with the n-terminal part of r. eutropha hoxf. however, in cyanobacteria, hoxe contains a 2fe-2s cluster-binding motif that is not found in the related r. eutropha sequence. in order to obtain some insights into the r ... | 2011 | 21848671 |
| A Trimeric Supercomplex of the Oxygen-Tolerant Membrane-Bound [NiFe]-Hydrogenase from Ralstonia eutropha H16. | The oxygen-tolerant membrane-bound [NiFe]-hydrogenase (MBH) from Ralstonia eutropha H16 consists of three subunits. The large subunit HoxG carries the [NiFe] active site, and the small subunit HoxK contains three [FeS] clusters. Both subunits form the so-called hydrogenase module, which is oriented toward the periplasm. Membrane association is established by a membrane-integral cytochrome b subunit (HoxZ) that transfers the electrons from the hydrogenase module to the respiratory chain. So far, ... | 2011 | 22097922 |
| Microalgae as bioreactors for bioplastic production. | Poly-3-hydroxybutyrate (PHB) is a polyester with thermoplastic properties that is naturally occurring and produced by such bacteria as Ralstonia eutropha H16 and Bacillus megaterium. In contrast to currently utilized plastics and most synthetic polymers, PHB is biodegradable, and its production is not dependent on fossil resources making this bioplastic interesting for various industrial applications. | 2011 | 22004563 |
| Genotypic and phenotypic diversity of Ralstonia pickettii and Ralstonia insidiosa isolates from clinical and environmental sources including High-purity Water. Diversity in Ralstonia pickettii. | Ralstonia pickettii is a nosocomial infectious agent and a significant industrial contaminant. It has been found in many different environments including clinical situations, soil and industrial High Purity Water. This study compares the phenotypic and genotypic diversity of a selection of strains of Ralstonia collected from a variety of sources. | 2011 | 21878094 |
| Enhanced incorporation of 3-hydroxy-4-methylvalerate unit into biosynthetic polyhydroxyalkanoate using leucine as a precursor. | ABSTRACT: Ralstonia eutropha PHB-4 expressing Pseudomonas sp. 61-3 polyhydroxyalkanoate (PHA) synthase 1 (PhaC1Ps) synthesizes PHA copolymer containing 3-hydroxybutyrate (3HB) and a small amount (0.5 mol%) of 3-hydroxy-4-methylvalerate (3H4MV) from fructose as a carbon source. In this study, enhanced incorporation of 3H4MV into PHA was investigated using branched amino acid leucine as a precursor of 3H4MV. Leucine has the same carbon backbone as 3H4MV and is expected to be a natural and self-pro ... | 2011 | 21906338 |
| microbial preference for different size classes of organic carbon: a study from antarctic snow. | significance of carbon cycling in polar ecosystems is well recognized. yet, bacteria in surface snow have received less attention in terms of their potential in carbon cycling. here, we present results on carbon utilization by bacterial communities in three surface snow samples from antarctica collected along a coastal to inland transect. microcosm studies were conducted over 8 days at 5 ± 1°c to study carbon metabolism in different combinations of added low molecular weight (lmw (glucose, <1 kd ... | 2011 | 22037862 |
| comparative effect of low temperature on virulence and twitching motility of ralstonia solanacearum strains present in florida. | abstract ralstonia solanacearum causes bacterial wilt on a wide range of plant hosts. most strains of r. solanacearum are nonpathogenic below 20°c; however, race 3 biovar 2 (r3b2) strains are classified as quarantine pathogens because of their ability to infect crops, cause disease, and survive in temperate climates. we have identified race 1 biovar 1 phylotype iib sequevar 4 strains present in florida which were able to infect and produce wilt symptoms on potato and tomato at 18°c. moreover t ... | 2011 | 21936660 |
| Rapid selection of glucose-utilizing variants of the polyhydroxyalkanoate producer Ralstonia eutropha H16 by incubation with high substrate levels. | Aims: The application of Ralstonia eutropha H16 for producing polyhydroxyalkanoates as bioplastics is limited by the incapability of the bacterium to utilize glucose as a growth substrate. This study aims in characterizing glucose-utilizing strains that arose after incubation with high glucose levels, in comparison with previously published mutants, generated either by mutagenesis or by metabolic engineering. Methods and Results: Cultivations on solid and liquid media showed that the applicati ... | 2012 | 22044343 |
| production of 3-hydroxypropionate homopolymer and poly(3-hydroxypropionate-co-4-hydroxybutyrate) copolymer by recombinant escherichia coli. | conversion of 3-hydroxypropionate (3hp) from 1,3-propanediol (pdo) was improved by expressing dehydratase gene (dhat) and aldehyde dehydrogenase gene (aldd) of pseudomonas putida kt2442 under the promoter of phacab operon from ralstonia eutropha h16. expression of these genes in aeromonas hydrophila 4ak4 produced up to 21 g/l 3hp in a fermentation process. to synthesize homopolymer poly(3-hydroxypropionate) (p3hp), and copolymer poly(3-hydroxypropionate-co-3-hydroxybutyrate) (p3hp4hb), dhat and ... | 2011 | 22024131 |
| predicting metabolic pathways by sub-network extraction. | various methods result in groups of functionally related genes obtained from genomes (operons, regulons, syntheny groups, and phylogenetic profiles), transcriptomes (co-expression groups) and proteomes (modules of interacting proteins). when such groups contain two or more enzyme-coding genes, graph analysis methods can be applied to extract a metabolic pathway that interconnects them. we describe here the way to use the pathway extraction tool available on the neat web server ( ... | 2012 | 22144151 |
| expression of polyhydroxybutyric acid as a model for metabolic engineering of soybean seed coats. | the feasibility of genetically engineering soybean seed coats to divert metabolism towards the production of novel biochemicals was tested. the genes phba, phbb, phbc from ralstonia eutropha each under the control of the seed coat peroxidase promoter were introduced into soybean and the production of polyhydroxybutyrate (phb) was assayed. the analysis of seed coats arising from 4 independent transformation events demonstrated that phb was produced at a mean of 0.12% seed coat dried weight with i ... | 2011 | 22183687 |
| [the first experience of application of pcr techniques in real-time mode to diagnose bacteriemia during postoperational period in cardiosurgery patients]. | the results comparison is made between pcr polymerase chain reaction techniques in real-time mode and cultural techniques of analysis of blood samples in patients with suspicion of bacteriemia during early postoperational period. from september to december 2009 43 blood samples from 37 adult patients aged 59+9.2 years were analyzed on suspicion of bacteriemia. the blood samples for pcr analysis (septifast technique roche diagnostics, switzerland) were taken parallel to the inoculation. among 43 ... | 2011 | 22164420 |
| improved biovar test for ralstonia solanacearum. | race 3, biovar 2 strains of ralstonia solanacearum are quarantined pathogens in europe and canada and select agent pathogens in the united states. the biovar classification of r. solanacearum strains is based on their biochemical abilities to utilize a carbohydrate panel. the standard biovar test uses bromothymol blue as a ph indicator in 15ml culture tubes containing 3 to 5ml of test media, and takes weeks to complete at 24 or 28°c. we improved the biovar test by using phenol red as a ph indica ... | 2011 | 22200550 |
| long-term field fertilization alters the diversity of autotrophic bacteria based on the ribulose-1,5-biphosphate carboxylase/oxygenase (rubisco) large-subunit genes in paddy soil. | carbon dioxide (co(2)) assimilation by autotrophic bacteria is an important process in the soil carbon cycle with major environmental implications. the long-term impact of fertilizer on co(2) assimilation in the bacterial community of paddy soils remains poorly understood. to narrow this knowledge gap, the composition and abundance of co(2)-assimilating bacteria were investigated using terminal restriction fragment length polymorphism and quantitative pcr of the cbbl gene [that encodes ribulose- ... | 2011 | 22159889 |
| Contrasting recombination patterns and demographic histories of the plant pathogen Ralstonia solanacearum inferred from MLSA. | We used multilocus sequence analysis (MLSA) on a worldwide collection of the plant pathogenic Ralstonia solanacearum (Betaproteobacteria) to retrace its complex evolutionary history. Using genetic imprints left during R. solanacearum evolution, we were able to delineate distinct evolutionary complex displaying contrasting dynamics. Among the phylotypes already described (I, IIA, IIB, III, IV), eight groups of strains with distinct evolutionary patterns, named clades, were identified. From our re ... | 2011 | 22094345 |
| Aerobic pretreatment of olive oil mill wastewater using Ralstonia eutropha. | Olive oil mill wastewater (OMW) has a high polluting power, with total phenolics (TP) around 2.5 g l(-1) and chemical oxygen demand (COD) 85 g l(-1). Biological systems offer advantages in treating this type of agro-industrial wastewater. The performance of phenol-adapted Ralstonia eutropha for aerobic biotreatment of OMW has been studied, and a TP concentration of 250 mg l(-1) found to be fully degraded within 24 h. This simple procedure may be adopted as a pretreatment prior to the normal aero ... | 2011 | 21882561 |
| Physiological conditions conducive to high cell density and high cyanophycin content in Ralstonia eutropha strain H16 possessing a KDPG aldolase gene-dependent addiction system. | The recombinant strain of Ralstonia eutropha H16-PHB(-)4-?eda (pBBR1MCS-2::cphA (6308)/eda (H16)) presenting a 2-keto-3-desoxy-phosphogluconate (KDPG) aldolase (eda) gene-dependent catabolic addiction system for plasmid maintenance when using gluconate or fructose as sole carbon source was used in this study. The effects of the initial pH, the nitrogen-to-carbon ratio, the inorganic components of medium, the oxygen supply, and the different carbon and ni ... | 2011 | 22080348 |
| Development and validation of an HPLC-based screening method to acquire polyhydroxyalkanoate synthase mutants with altered substrate specificity. | A rapid and convenient method for the compositional analysis of polyhydroxyalkanoate (PHA) was developed using high-performance liquid chromatography (HPLC) and alkaline sample pretreatment in a 96-well plate format. The reliability of this system was confirmed by the fact that a mutant with a D171G mutation of Aeromonas caviae PHA synthase (PhaC(Ac)), which gained higher reactivity toward 3-hydroxyhexanoate (3HHx), was selected from the D171X mutant library. Together with D171G mutant, several ... | 2011 | 22088761 |
| probing the origin of the metabolic precursor of the co ligand in the catalytic center of [nife] hydrogenase. | the o(2)-tolerant [nife] hydrogenases of ralstonia eutropha are capable of h(2) conversion in the presence of ambient o(2). oxygen represents not only a challenge for catalysis but also for the complex assembling process of the [nife] active site. apart from nickel and iron, the catalytic center contains unusual diatomic ligands, namely two cyanides (cn(-)) and one carbon monoxide (co), which are coordinated to the iron. one of the open questions of the maturation process concerns the origin and ... | 2011 | 22049085 |
| the origin and ecological significance of multiple branches for histidine utilization in pseudomonas aeruginosa pao1. | pseudomonas proliferate in a wide spectrum of harsh and variable environments. in many of these environments, amino acids, such as histidine, are a valuable source of carbon, nitrogen and energy. here, we demonstrate that the histidine uptake and utilization (hut) pathway of pseudomonas aeruginosa pao1 contains two branches from the intermediate formiminoglutamate to the product glutamate. genetic analysis revealed that the four-step route is dispensable as long as the five-step route is present ... | 2012 | 22225844 |