a rhizospheric burkholderia cepacia complex population: genotypic and phenotypic diversity of burkholderia cenocepacia and burkholderia ambifaria.the burkholderia cepacia'complex' (bcc) presently comprises nine species and genomovars. in order to acquire a better comprehension of the species and genomovar distribution and of the genetic diversity among environmental bcc bacteria, a natural population of 60 bacterial isolates recovered from the rhizosphere of maize and belonging to the bcc has been characterised to assess the exact taxonomic position, the genetic polymorphism and the metabolic profiles of isolates. the identification of th ...200319719571
production of the antifungal compound pyrrolnitrin is quorum sensing-regulated in members of the burkholderia cepacia complex.members of the genus burkholderia are known for their ability to suppress soil-borne fungal pathogens by the production of various antibiotic compounds. in this study we investigated the role of n-acylhomoserine lactone (ahl)-dependent quorum sensing (qs) in the expression of antifungal traits. using a quorum quenching approach, that is, by heterologous expression of the bacillus sp. aiia lactonase, we show that expression of antifungal activities is ahl-dependent in the large majority of the in ...200919220396
burkholderia ambifaria sp. nov., a novel member of the burkholderia cepacia complex including biocontrol and cystic fibrosis-related isolates.a polyphasic taxonomic study, including amplified fragment length polymorphism (aflp) fingerprinting, dna-dna hybridizations, dna base-ratio determinations, phylogenetic analysis, whole-cell fatty acid analyses and an extensive biochemical characterization, was performed on 19 burkholderia cepacia-like isolates from the environment and cystic fibrosis (cf) patients. several of the environmental isolates have attracted considerable interest due to their biocontrol properties. the polyphasic taxon ...200111491349
plant host and sugar alcohol induced exopolysaccharide biosynthesis in the burkholderia cepacia complex.the species that presently constitute the burkholderia cepacia complex (bcc) have multiple roles; they include soil and water saprophytes, bioremediators, and plant, animal and human pathogens. since the first description of pathogenicity in the bcc was based on sour skin rot of onion bulbs, this study returned to this plant host to investigate the onion-associated phenotype of the bcc. many bcc isolates, which were previously considered to be non-mucoid, produced copious amounts of exopolysacch ...200818667584
burkholderia respiratory tract infections in italian patients with cystic fibrosis: molecular characterize by molecular techniques burkholderia strains responsible for respiratory tract infections in cystic fibrosis (cf) patients (children and adults), to assign the burkholderia cepacia complex (bcc) isolates to a genomovar and to assess the presence of cbla and esmr genes in bacteria. unique or sequential burkholderia isolates (n=48) that had been collected from eight cf children and 17 adults over several (4-6) years were investigated; moreover 11 reference strains were analyzed.200616375971
dna microarray-based detection and identification of burkholderia mallei, burkholderia pseudomallei and burkholderia spp.we developed a rapid oligonucleotide microarray assay based on genetic markers for the accurate identification and differentiation of burkholderia (b.) mallei and burkholderia pseudomallei, the agents of glanders and melioidosis, respectively. these two agents were clearly identified using at least 4 independent genetic markers including 16s rrna gene, flic, motb and also by novel species-specific target genes, identified by in silico sequence analysis. specific hybridization signal profiles all ...200919366627
differentiation of species combined into the burkholderia cepacia complex and related taxa on the basis of their fatty acid patterns.using the established commercial system sherlock (midi, inc.), cellular fatty acid methyl ester analysis for differentiation among burkholderia cepacia complex species was proven. the identification key based on the diagnostic fatty acids is able to discern phenotypically related ralstonia pickettii and pandoraea spp. and further distinguish burkholderia pyrrocinia, burkholderia ambifaria, and burkholderia vietnamiensis.200616517920
polymicrobial keratitis secondary to burkholderia ambifaria, enterococcus, and staphylococcus aureus in a patient with herpetic stromal report polymicrobial keratitis in a patient with herpetic stromal keratitis. the initial infecting organism, burkholderia ambifaria, has not previously been reported to cause microbial keratitis.200314516823
enacyloxins are products of an unusual hybrid modular polyketide synthase encoded by a cryptic burkholderia ambifaria genomic island.gram-negative burkholderia cepacia complex (bcc) isolates were screened for antimicrobial activity against cystic fibrosis microbial pathogens, and the ability of b. ambifaria to inhibit b. multivorans was identified. the activity was mapped to a cluster of cryptic, quorum-sensing-regulated modular polyketide synthase (pks) genes. enacyloxin iia and its stereoisomer designated iso-enacyloxin iia were identified as metabolic products of the gene cluster, which encoded an unusual hybrid modular pk ...201121609847
ahl-deficient mutants of burkholderia ambifaria bc-f have decreased antifungal activity.burkholderia ambifaria bc-f, a biocontrol strain reported previously to exhibit broad-spectrum antifungal activity, was highly active in formation of n-acyl homoserine lactones (ahls). we constructed ahl-deficient derivatives of strain bc-f in which the genes specifying ahl synthase (bafi) and ahl-binding transcriptional activator (bafr) were inactivated by allelic exchange. the resulting ahl-deficient mutants had decreased antifungal activity.200314570265
metabolic profiling of burkholderia cenocepacia, burkholderia ambifaria, and burkholderia pyrrocinia isolates from maize rhizosphere.burkholderia cenocepacia, burkholderia ambifaria, and burkholderia pyrrocinia are the burkholderia cepacia complex (bcc) species most frequently associated with roots of crop plants. to investigate the ecophysiological diversity of these species, metabolic profiling of maize rhizosphere isolates was carried out by means of the biolog system, using gn2 and sfn2 plates and different parameters related to optical density (od). the metabolic profiles produced by the sfn2 and gn2 plates were identica ...200516328653
effects of two different application methods of burkholderia ambifaria mci 7 on plant growth and rhizospheric bacterial order to acquire a better understanding of the effects of the different delivery modes of bacterial inoculants on plant growth and on the community structure of rhizosphere bacterial populations, burkholderia ambifaria mci 7 (formerly b. cepacia mci 7) was inoculated into the rhizosphere of maize plants by either seed adhesion or incorporation into soil. plant growth was evaluated at different inoculum concentrations. the community structure of rhizosphere bacterial populations was evaluated ...200212010130
suppression-subtractive hybridisation reveals variations in gene distribution amongst the burkholderia cepacia complex, including the presence in some strains of a genomic island containing putative polysaccharide production genes.some strains of the burkholderia cepacia complex, including the et12 lineage, have been implicated in epidemic spread amongst cystic fibrosis (cf) patients. suppression-subtractive hybridisation was used to identify genomic regions within strain j2315 (et12 lineage; genomovar iiia) that were absent from a non-transmissible genomovar iiib strain. sequence data from 15 subtracted clones were used to interrogate the genome sequence of strain j2315 and identify genomic regions incorporating the subt ...200312610727
phase variation has a role in burkholderia ambifaria niche adaptation.members of the burkholderia cepacia complex (bcc), such as b. ambifaria, are effective biocontrol strains, for instance, as plant growth-promoting bacteria; however, bcc isolates can also cause severe respiratory infections in people suffering from cystic fibrosis (cf). no distinction is known between isolates from environmental and human origins, suggesting that the natural environment is a potential source of infectious bcc species. while investigating the presence and role of phase variation ...201019710710
small molecule inhibition of choline catabolism in pseudomonas aeruginosa and other aerobic choline-catabolizing bacteria.choline is abundant in association with eukaryotes and plays roles in osmoprotection, thermoprotection, and membrane biosynthesis in many bacteria. aerobic catabolism of choline is widespread amongst soil proteobacteria, particularly those associated with eukaryotes. catabolism of choline as a carbon, nitrogen, and/or energy source may play important roles in association with eukaryotes, including pathogenesis, symbioses, and nutrient cycling. we sought to generate choline analogues to study bac ...201121602374
[cloning of silkworm 3-hydroxyisobutyrate dehydrogenase gene and its expression patterns analysis in simulated weightless environment].the full length cdna of silkworm hibadh gene was cloned by rt-pcr and race (rapid amplification of cdna ends) technique. the hibadh gene and its deduced amino acid sequences were analyzed. the tissue distribution of hibadh gene in 5th instar silkworm larvae was tested by rt-pcr. the expression patterns of hibadh gene in simulated weightless environment were analyzed by real time rt-pcr. the results showed that the full length hibadh cdna sequence was 1074 bp in lenth, including an open read fram ...200819306573
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 ...201122170069
quorum sensing in acinetobacter: an emerging pathogen.acinetobacter is emerging as one of the major nosocomial infectious pathogens, facilitated by tolerance to desiccation and multidrug resistance. quorum sensing (autoinducer-receptor mechanism) plays role in biofilm formation in acinetobacter, though its role in regulation of other virulence factors is yet to be established. phylogenetic studies indicate that acinetobacter baumannii is closely related to burkholderia ambifaria but its quorum sensing genes (abai and abar) were acquired horizontall ...201020846031
pyrosequencing of a reca gene variable region for burkholderia cepacia complex genomovar identification.we developed an assay to identify burkholderia cepacia complex genomovars by pyrosequencing of a variable reca gene segment. fifteen reference strains and 30 clinical isolates of b. cepacia complex were sequenced. full 77-base pair target sequences were obtained from 44 of the 45 isolates, and blast queries of the sequences correctly identified the genomovar of these 44 isolates. three burkholderia multivorans isolates were identified as b. multivorans/burkholderia ambifaria, indicating that add ...200717509790
characterization of the poly-β-1,6-n-acetylglucosamine polysaccharide component of burkholderia biofilms.we demonstrated the production of poly-β-1,6-n-acetylglucosamine (pnag) polysaccharide in the biofilms of burkholderia multivorans, burkholderia vietnamiensis, burkholderia ambifaria, burkholderia cepacia, and burkholderia cenocepacia using an immunoblot assay for pnag. these results were confirmed by further studies, which showed that the pnag hydrolase, dispersin b, eliminated immunoreactivity of extracts from the species that were tested (b. cenocepacia and b. multivorans). dispersin b also i ...201121984237
multiscale responses of microbial life to spatial distance and environmental heterogeneity in a patchy ecosystem.spatial distance (sd) and environmental heterogeneity (eh) are currently thought to represent major factors shaping genetic variation and population abundance, but their relative importance is still poorly understood. because eh varies at multiple spatial scales, so too are microbial variables expected to vary. the determination of sd x eh interactions at multiple scales is, however, not a trivial exercise, especially when one examines their effects on microbial abundance and genomic similaritie ...200717296935
crystal structure of a novel n-substituted l-amino acid dioxygenase from burkholderia ambifaria ammd.a novel dioxygenase from burkholderia ambifaria ammd (sada) stereoselectively catalyzes the c3-hydroxylation of n-substituted branched-chain or aromatic l-amino acids, especially n-succinyl-l-leucine, coupled with the conversion of α-ketoglutarate to succinate and co2. to elucidate the structural basis of the substrate specificity and stereoselective hydroxylation, we determined the crystal structures of the sada.zn(ii) and sada.zn(ii).α-kg complexes at 1.77 å and 1.98 å resolutions, respectivel ...201323724013
a novel fe(ii)/α-ketoglutarate-dependent dioxygenase from burkholderia ambifaria has β-hydroxylating activity of n-succinyl fe(ii)/α-ketoglutarate-dependent dioxygenase, sada, was obtained from burkholderia ambifaria ammd and heterologously expressed in escherichia coli. purified recombinant sada had catalytic activity towards several n-substituted l-amino acids, which was especially strong with n-succinyl l-leucine. with the nmr and lc-ms analysis, sada converted n-succinyl l-leucine into n-succinyl l-threo-β-hydroxyleucine with >99% diastereoselectivity. sada is the first enzyme catalysing β-hydroxylation of ali ...201222967283
structural identification of the o-antigen fraction from the lipopolysaccharide of the burkholderia ambifaria strain 19182.the burkholderia cepacia complex comprises a group of bacterial strains with both beneficial and detrimental effects to plant and animals. gram negative bacterial lipopolysaccharide is one of the most important molecular factors involved in the dialogue between the microbe and the host and in this context we have isolated and identified the o-antigen fraction of the burkholderia ambifaria strain 19182. it consists of two different o-polysaccharides built up on 6-deoxy sugars, among which the 6-d ...201323886988
genomovar diversity amongst burkholderia cepacia complex isolates from an australian adult cystic fibrosis this study, a combination of reca-based pcr assays and 16s rdna restriction fragment length polymorphism (rflp) analysis was used to determine the genomovar diversity of clinical burkholderia cepacia complex isolates. twenty-eight isolates were prospectively collected from patients attending a large australian adult cystic fibrosis (cf) unit, 22 isolates were referred from other australian cf units and a further eight isolates originated from patients without cf. the 28 prospectively collecte ...200312884074
detection of cultured and uncultured burkholderia cepacia complex bacteria naturally occurring in the maize rhizosphere.the species composition of a burkholderia cepacia complex population naturally occurring in the maize rhizosphere was investigated by using both culture-dependent and culture-independent methods. b. cepacia complex isolates were recovered from maize root slurry on the two selective media pseudomonas cepacia azelaic acid tryptamine (pcat) and trypan blue tetracycline (tb-t) and subjected to identification by a combination of restriction fragment length polymorphism (rflp) analysis and species-spe ...200516232288
pentavalent pillar[5]arene-based glycoclusters and their multivalent binding to pathogenic bacterial lectins.anti-adhesive glycoclusters offer potential as therapeutic alternatives to classical antibiotics in treating infections. pillar[5]arenes functionalised with either five galactose or five fucose residues were readily prepared using cuaac reactions and evaluated for their binding to three therapeutically relevant bacterial lectins: leca and lec b from pseudomonas aeuruginosa and bambl from burkholderia ambifaria. steric interactions were demonstrated to be a key factor in achieving good binding to ...201626972051
pillar[5]arene-based glycoclusters: synthesis and multivalent binding to pathogenic bacterial lectins.the synthesis of pillar[5]arene-based glycoclusters has been readily achieved by cuaac conjugations of azido- and alkyne-functionalized precursors. the lectin binding properties of the resulting glycosylated multivalent ligands have been studied by at least two complementary techniques to provide a good understanding. three lectins were selected from bacterial pathogens based on their potential therapeutic applications as anti-adhesives, namely leca and lecb from pseudomonas aeruginosa and bambl ...201626845383
burkholderia cepacia complex: distribution of genomovars among isolates from the maize rhizosphere in italy.burkholderia cepacia is a 'complex' in which seven genomic species or genomovars have so far been identified. it appears that all seven b. cepacia genomovars are capable of causing infections in vulnerable persons; in particular, the importance of burkholderia multivorans (genomovar ii) and b. cepacia genomovar iii among cystic fibrosis isolates, especially epidemic ones, has been emphasized. in order to acquire a better comprehension of the genomovar composition of environmental populations of ...200111321544
accurate identification of members of the burkholderia cepacia complex in cystic fibrosis sputum.the burkholderia cepacia complex (bcc) is a group of closely related species which includes opportunistic pathogens causing chronic respiratory infections in immunocompromised patients, or individuals affected by cystic fibrosis (cf). other burkholderia species causing infection in the cf population are burkholderia gladioli and burkholderia pseudomallei. traditional phenotypic analyses have been demonstrated to be inadequate for reliable identifications of isolates of bcc and b. gladioli. a pan ...201626671758
antibacterial activity of a lectin-like burkholderia cenocepacia protein.bacteriocins of the llpa family have previously been characterized in the γ-proteobacteria pseudomonas and xanthomonas. these proteins are composed of two mmbl (monocot mannose-binding lectin) domains, a module predominantly and abundantly found in lectins from monocot plants. genes encoding four different types of llpa-like proteins were identified in genomes from strains belonging to the burkholderia cepacia complex (bcc) and the burkholderia pseudomallei group. a selected recombinant llpa-lik ...201323737242
deciphering the glycan preference of bacterial lectins by glycan array and molecular docking with validation by microcalorimetry and crystallography.recent advances in glycobiology revealed the essential role of lectins for deciphering the glycocode by specific recognition of carbohydrates. integrated multiscale approaches are needed for characterizing lectin specificity: combining on one hand high-throughput analysis by glycan array experiments and systematic molecular docking of oligosaccharide libraries and on the other hand detailed analysis of the lectin/oligosaccharide interaction by x-ray crystallography, microcalorimetry and free ene ...201323976992
importance of topology for glycocluster binding to pseudomonas aeruginosa and burkholderia ambifaria bacterial lectins.pseudomonas aeruginosa (pa) and burkholderia ambifaria (ba) are two opportunistic gram negative bacteria and major infectious agents involved in lung infection of cystic fibrosis patients. both bacteria can develop resistance to conventional antibiotherapies. an alternative strategy consists of targeting virulence factors in particular lectins with high affinity ligands such as multivalent glycoclusters. leca (pa-il) and lecb (pa-iil) are two tetravalent lectins from pa that recognise galactose ...201526412676
polyclonal outbreak of bacteremia caused by burkholderia cepacia complex and the presumptive role of ultrasound gel.a nosocomial polyclonal outbreak associated to bacteremia caused by different burkholderia cepacia complex (bcc) species and clones is reported. molecular characterization identified burkholderia stabilis, burkholderia contaminans, and burkholderia ambifaria among bcc isolates obtained from patients in neonatal and adult intensive care units. bcc was also isolated from an intrinsically contaminated ultrasound gel, which constituted the presumptive bcc source. prior bcc outbreak related to contam ...201526322722
structural optimization of sada, an fe(ii)- and α-ketoglutarate-dependent dioxygenase targeting biocatalytic synthesis of n-succinyl-l-threo-3,4-dimethoxyphenylserine.l-threo-3,4-dihydroxyphenylserine (l-dops, droxidopa) is a psychoactive drug and synthetic amino acid precursor that acts as a prodrug to the neurotransmitters. sada, a dioxygenase from burkholderia ambifaria ammd, is an fe(ii)- and α-ketoglutarate (kg)-dependent enzyme that catalyzes n-substituted branched-chain or aromatic l-amino acids. sada is able to produce n-succinyl-l-threo-3,4-dimethoxyphenylserine (nsdops), which is a precursor of l-dops, by catalyzing the hydroxylation of n-succinyl-3 ...201425017911
loline alkaloid production by fungal endophytes of fescue species select for particular epiphytic bacterial microflora.the leaves of fescue grasses are protected from herbivores by the production of loline alkaloids by the mutualist fungal endophytes neotyphodium sp. or epichloë sp. most bacteria that reside on the leaf surface of such grasses can consume these defensive chemicals. loline-consuming bacteria are rare on the leaves of other plant species. several bacterial species including burkholderia ambifaria recovered from tall fescue could use n-formyl loline as a sole carbon and nitrogen source in culture a ...201324108329
evaluation of restriction fragment length polymorphism analysis of 16s rdna as a tool for genomovar characterisation within the burkholderia cepacia complex.a total of 154 burkholderia cepacia complex strains, isolated from cystic fibrosis and non-cystic fibrosis patients and the environment, representing all nine genomovars and a putative tenth, were analysed by 16s rdna-restriction fragment length polymorphism using the restriction enzymes alui, cfoi and ddei. examining this diverse strain collection resulted in very diverse restriction patterns. only b. cepacia genomovar vi could be identified unambiguously. the same restriction patterns were obs ...200212204364
synthesis of a selective inhibitor of a fucose binding bacterial lectin from burkholderia ambifaria.burkholderia ambifaria is a bacterium member of the burkholderia cepacia complex (bcc), a closely related group of gram-negative bacteria responsible for "cepacia syndrome" in immunocompromised patients. b. ambifaria produces bambl, a fucose-binding lectin that displays fine specificity to human fucosylated epitopes. here, we report the first example of a synthetic ligand able to selectively bind, in the micromolar range, the pathogen-lectin bambl. the synthetic routes for the preparation of the ...201323673818
distinct colicin m-like bacteriocin-immunity pairs in burkholderia.the escherichia coli bacteriocin colicin m (colm) acts via degradation of the cell wall precursor lipid ii in target cells. colm producers avoid self-inhibition by a periplasmic immunity protein anchored in the inner membrane. in this study, we identified colm-like bacteriocin genes in genomes of several β-proteobacterial strains belonging to the burkholderia cepacia complex (bcc) and the burkholderia pseudomallei group. two selected burkholderia ambifaria proteins, designated burkhocins m1 and ...201526610609
burkholdines from burkholderia ambifaria: antifungal agents and possible virulence factors.burkholdines are cyclic lipopeptides with unusual antifungal potency, making them promising leads as a new class of antifungal agents. however, a recent report using knockout mutagenesis indicates that these and related compounds, such as occidiofungins, xylocandins, and cepacidines, may also be synonymous with the long-known hemolytic virulence factors found in diverse burkholderia isolates. because of their possible roles in causing burkholderia infections or curing fungal infections, it is im ...201222988812
burkholderia ambifaria and b. caribensis promote growth and increase yield in grain amaranth (amaranthus cruentus and a. hypochondriacus) by improving plant nitrogen uptake.grain amaranth is an emerging crop that produces seeds having high quality protein with balanced amino-acid content. however, production is restricted by agronomic limitations that result in yields that are lower than those normally produced by cereals. in this work, the use of five different rhizobacteria were explored as a strategy to promote growth and yields in amaranthus hypochondriacus cv. nutrisol and a. cruentus cv. candil, two commercially important grain amaranth cultivars. the plants ...201424533068
synthesis of a disaccharide repeating unit of the o-antigen from burkholderia ambifaria and its oligomers.a disaccharide repeating unit of the o-antigen from burkholderia ambifaria, 6-deoxy-β-d-alt-(1 → 4)-α-d-rha-o(ch2)3nh2 (1), and its dimer and trimer, 6-deoxy-β-d-alt-(1 → 4)-α-d-rha-(1 → 3)-6-deoxy-β-d-alt-(1 → 4)-α-d-rha-o(ch2)3nh2 (2) and 6-deoxy-β-d-alt-(1 → 4)-α-d-rha-(1 → 3)-6-deoxy-β-d-alt-(1 → 4)-α-d-rha-(1 → 3)-6-deoxy-β-d-alt-(1 → 4)-α-d-rha-o(ch2)3nh2 (3), were synthesized via a convergent strategy. the key disaccharyl thioglycoside 4 as a glycosyl donor was stereoselectively assembled ...201728288346
draft genome sequence of burkholderia ambifaria rz2ms16, a plant growth-promoting rhizobacterium isolated from guarana, a tropical plant.burkholderia ambifaria strain rz2ms16 was isolated from the rhizosphere of amazon guarana in brazil. this bacterium exhibits a remarkable capacity to promote the growth of corn and soybean. here, we report the draft genome sequence of rz2ms16 and some genes related to multiple traits involved in plant growth promotion.201626988044
in vitro and in vivo inoculation of four endophytic bacteria on lycopersicon esculentum.four bacteria selected on the basis of their capability of fixing atmospheric nitrogen, stimulating plant-growth, and protecting the host plant from pathogens - azospirillum brasilense, gluconacetobacter diazotrophicus, herbaspirillum seropedicae, burkholderia ambifaria - were inoculated on tomato seeds either singularly, in couple and in a four bacteria mixer. aim of this research was to evaluate: (1) effect of single and mixed cultures on the inoculated plant - plant growth, dry weight, root l ...201323352842
kdo hydroxylase is an inner core assembly enzyme in the ko-containing lipopolysaccharide biosynthesis.the lipopolysaccharide (lps) isolated from certain important gram-negative pathogens including a human pathogen yersinia pestis and opportunistic pathogens burkholderia mallei and burkholderia pseudomallei contains d-glycero-d-talo-oct-2-ulosonic acid (ko), an isosteric analog of 3-deoxy-d-manno-oct-2-ulosonic acid (kdo). kdo 3-hydroxylase (kdoo), a fe(2+)/α-kg/o2 dependent dioxygenase from burkholderia ambifaria and yersinia pestis is responsible for ko formation with kdo2-lipid a as a substrat ...201425204504
expression, purification, crystallization and preliminary x-ray analysis of a novel n-substituted branched-chain l-amino-acid dioxygenase from burkholderia ambifaria ammd.ferrous ion- and α-ketoglutarate-dependent dioxygenase from burkholderia ambifaria ammd (sada) catalyzes the c3-hydroxylation of n-substituted branched-chain l-amino acids, especially n-succinyl-l-leucine, coupled to the conversion of α-ketoglutarate to succinate and co(2). sada was expressed in escherichia coli, purified and crystallized using the sitting-drop vapour-diffusion method at 293 k. crystals of selenomethionine-substituted sada were obtained using a reservoir solution containing peg ...201222949196
identification of quorum sensing-controlled genes in burkholderia ambifaria.the burkholderia cepacia complex (bcc) comprises strains with a virulence potential toward immunocompromised patients as well as plant growth-promoting rhizobacteria (pgpr). owing to the link between quorum sensing (qs) and virulence, most studies among bcc species have been directed toward qs of pathogenic bacteria. we have investigated the qs of b. ambifaria, a pgpr only infrequently recovered from patients. the cepi gene, responsible for the synthesis of the main signaling molecule n-octanoyl ...201323382083
effects of selected diazotrophs on maize growth.laboratory, greenhouse, and field experiments were conducted at the university of kwazulu-natal, pietermaritzburg, south africa in the 2010/2011 and 2011∖2012 seasons to study the effects of eight strains of diazotrophic bacteria on the growth and yield of maize. maize seeds were treated with bacillus megaterium (v16), pseudomonas sp. (stb5, a3, a6, and a61), burkholderia ambifaria (v9), enterobacter cloacae (l1) and pantoea ananatis (lb5), aiming to stimulate plant growth, and maintain or incre ...201627713756
burkholderia genome mining for nonribosomal peptide synthetases reveals a great potential for novel siderophores and lipopeptides synthesis.burkholderia is an important genus encompassing a variety of species, including pathogenic strains as well as strains that promote plant growth. we have carried out a global strategy, which combined two complementary approaches. the first one is genome guided with deep analysis of genome sequences and the second one is assay guided with experiments to support the predictions obtained in silico. this efficient screening for new secondary metabolites, performed on 48 gapless genomes of burkholderi ...201627060604
dioxygenases in burkholderia ambifaria and yersinia pestis that hydroxylate the outer kdo unit of lipopolysaccharide.several gram-negative pathogens, including yersinia pestis, burkholderia cepacia, and acinetobacter haemolyticus, synthesize an isosteric analog of 3-deoxy-d-manno-oct-2-ulosonic acid (kdo), known as d-glycero-d-talo-oct-2-ulosonic acid (ko), in which the axial hydrogen atom at the kdo 3-position is replaced with oh. here we report a unique kdo 3-hydroxylase (kdoo) from burkholderia ambifaria and yersinia pestis, encoded by the bamb_0774 (bakdoo) and the y1812 (ypkdoo) genes, respectively. when ...201021178073
production of bioactive volatiles by different burkholderia ambifaria strains.increasing evidence indicates that volatile compounds emitted by bacteria can influence the growth of other organisms. in this study, the volatiles produced by three different strains of burkholderia ambifaria were analysed and their effects on the growth of plants and fungi, as well as on the antibiotic resistance of target bacteria, were assessed. burkholderia ambifaria emitted highly bioactive volatiles independently of the strain origin (clinical environment, rhizosphere of pea, roots of mai ...201323832658
bioinformatic analysis of the acinetobacter baumannii phage ab1 one of the pathogens of hospital-acquired infections, acinetobacter baumannii poses great challenges to the public health. a. baumannii phage could be an effective way to fight multi-resistant a. baumannii. here, we completed the whole genome sequencing of the complete genome of a. baumannii phage ab1, which consists of 45,159 bp and is a double-stranded dna molecule with an average gc content of 37.7%. the genome encodes one trna gene and 85 open reading frames (orfs) and the average size of ...201222868206
burkholdines 1097 and 1229, potent antifungal peptides from burkholderia ambifaria 2.2n.potent antifungal cyclic lipopeptides, burkholdines (bk), were isolated from a culture of burkholderia ambifaria 2.2n. bk-1229 (1) and bk-1097 (2) are octapeptides comprised of nonproteinogenic amino acids, including beta-hydroxytyrosine, beta-hydroxyasparagine, and a new fatty acyl amino acid. 1 and 2 are fungicidal against a panel of fungi with potencies 2-60-fold better than amphotericin b control.201020085289
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