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identification of a novel virulence factor in burkholderia cenocepacia h111 required for efficient slow killing of caenorhabditis elegans.burkholderia cenocepacia h111, which was isolated from a cystic fibrosis patient, employs a quorum-sensing (qs) system, encoded by cep, to control the expression of virulence factors as well as the formation of biofilms. the qs system is thought to ensure that pathogenic traits are expressed only when the bacterial population density is high enough to overwhelm the host before it is able to mount an efficient response. while the wild-type strain effectively kills the nematode caenorhabditis eleg ...200415557647
burkholderia cenocepacia vaginal infection in patient with smoldering myeloma and chronic hepatitis c.we report a case of a vaginal infection caused by a strain of burkholderia cenocepacia. the strain was isolated from vaginal swab specimens from a 68-year-old woman with smoldering myeloma and chronic hepatitis c virus infection who was hospitalized for abdominal abscess. treatment with piperacillin/tazobactam eliminated b. cenocepacia infection and vaginal symptoms.200415550207
recovery of burkholderia cenocepacia strain phdc from cystic fibrosis patients in europe.burkholderia cenocepacia can cause life threatening respiratory tract infections in patients with cystic fibrosis (cf) and has a significant impact on survival. there is extensive evidence for patient to patient spread and nosocomial transmission of this organism, and several widespread b cenocepacia strains have been described including the transatlantic et12 clone. a study was performed to compare b cenocepacia isolates recovered from cf patients receiving care in several european countries an ...200415516470
burkholderia cenocepacia and burkholderia multivorans: influence on survival in cystic fibrosis.burkholderia cepacia infection has been associated with a poor prognosis for patients with cystic fibrosis (cf). it is now recognised that organisms classified as b cepacia comprise a number of distinct genomic species each known as a genomovar of the b cepacia complex (bcc). the outcome of infection for cf patients with individual genomovars is unknown. the clinical outcome of infection with the two most commonly isolated genomovars (b cenocepacia and b multivorans) was studied at a specialist ...200415516469
pcr-based identification and characterization of burkholderia cepacia complex bacteria from clinical and environmental sources.to study the genotypic identification and characterization of the 119 burkholderia cepacia complex (bcc) strains recovered from clinical and environmental sources in japan and thailand.200415482431
species distribution and ribotype diversity of burkholderia cepacia complex isolates from french patients with cystic fibrosis.a total of 153 burkholderia cepacia strains obtained from 153 french patients with cystic fibrosis were identified as burkholderia multivorans (51.6%) or burkholderia cenocepacia (45.1%). eighty-two genotypes were identified using pvuii and ecori ribotyping. b. multivorans genotype a (found in 32 french patients) and two other genotypes were also identified among isolates from austrian, german, italian, and canadian patients.200415472352
exopolysaccharides produced by burkholderia cenocepacia reca lineages iiia and iiib.clinical and environmental strains of burkholderia cenocepacia belonging to the reca lineages iiia and iiib were examined for exopolysaccharide (eps) production. the exopolysaccharides structure was determined using mainly gas chromatography coupled to mass spectrometry and nmr spectroscopy. all the strains produced cepacian, a highly branched polysaccharide constituted of a heptasaccharide repeating unit, composed of one rhamnose, one glucose, one glucuronic acid, one mannose and three galactos ...200415463903
clinical outcome of burkholderia cepacia complex infection in cystic fibrosis adults.the burkholderia cepacia complex (bcc) is one of the most important groups of organisms infecting cystic fibrosis (cf) patients. the aim of the study was to examine how infection with bcc affects clinical outcome.200415463892
burkholderia cepacia genomovar iii and burkholderia vietnamiensis double infection in a cystic fibrosis child.herein we report a case of a cystic fibrosis child who was simultaneously infected with burkholderia cepacia genomovar iii and burkholderia vietnamiensis. after antimicrobial therapy only b. cepacia genomovar iii persisted.200215463830
persistence of burkholderia multivorans within the pulmonary macrophage in the murine lung.differences in infection kinetics and host response between burkholderia multivorans and burkholderia cenocepacia were demonstrated in a pulmonary infection model in balb/c mice. b. multivorans persisted in the lung, while b. cenocepacia was cleared. indirect immunofluorescence and electron microscopy of b. multivorans-infected lungs localized bacteria to macrophages. clearance of b. cenocepacia was associated with greater interleukin-1beta and neutrophil responses than the responses induced by ...200415385520
involvement of a plasmid-encoded type iv secretion system in the plant tissue watersoaking phenotype of burkholderia cenocepacia.burkholderia cenocepacia strain k56-2, a representative of the burkholderia cepacia complex, is part of the epidemic and clinically problematic et12 lineage. the strain produced plant tissue watersoaking (ptw) on onion tissue, which is a plant disease-associated trait. using plasposon mutagenesis, mutants in the ptw phenotype were generated. the translated sequence of a disrupted gene (ptwd4) from a ptw-negative mutant showed homology to vird4-like proteins. analysis of the region proximal to th ...200415342570
contribution of burkholderia cenocepacia flagella to infectivity and inflammation.burkholderia cenocepacia is an opportunistic pathogen that can cause severe lung infections in cystic fibrosis patients. to understand the contribution of b. cenocepacia flagella to infection, a strain mutated in the major flagellin subunit, flicii, was constructed in b. cenocepacia k56-2 and tested in a murine agar bead model of lung infection. c57/bl6 mice infected with approximately 10(8) wild-type k56-2 bacteria exhibited 40% mortality after 3 days, whereas no mortality was noted in mice inf ...200415322006
common oligosaccharide moieties inhibit the adherence of typical and atypical respiratory pathogens.intervention in bacterial adhesion to host cells is a novel method of overcoming current problems associated with antibiotic resistance. antibiotic-resistant strains of bacteria that cause respiratory tract infections are a problem in hospitals and could be used in bioterrorist attacks. a range of bacterial species was demonstrated to attach to an alveolar epithelial (a549) cell line. in all cases, cell surface oligosaccharides were important in attachment, demonstrated by reduced adhesion when ...200415314189
production of exopolysaccharide by burkholderia cenocepacia results in altered cell-surface interactions and altered bacterial clearance in mice.despite the characterization of some burkholderia cepacia complex exopolysaccharides (epss), little is known about the role of epss in the pathogenicity of b. cepacia complex organisms. we describe 2 burkholderia cenocepacia (genomovar iii) isolates obtained from a patient with cystic fibrosis (cf): the nonmucoid isolate c8963 and the mucoid isolate c9343. both isolates had identical random amplified polymorphic dna patterns. c9343 produced a capsule composed of the epss ps-i and ps-ii, as well ...200415295701
epidemiology of burkholderia cepacia complex colonisation in cystic fibrosis patients.in belgian cystic fibrosis (cf) clinics, sputum samples are evaluated on selective mast medium routinely every 3 months. in this study, in 1993 and 1999, isolates were further examined by reca restriction fragment length polymorphism analysis and pulsed-field gel electrophoresis of genomic dna restricted with spei. in 1993, 12 patients were colonised with burkholderia cepacia complex (bcc): b. cenocepacia (n=6), b. multivorans (n=3), b. stabilis (n=3). four patients were colonised with the same ...200415218997
responses of well-differentiated airway epithelial cell cultures from healthy donors and patients with cystic fibrosis to burkholderia cenocepacia infection.well-differentiated cultures established from airway epithelia of patients with cystic fibrosis (cf cultures) exhibited goblet cell hyperplasia, increased secretion of mucus, and higher basal levels of interleukin-8 than similarly cultured cells from healthy donors. upon apical infection with low doses (10(4) to 10(5) cfu) of burkholderia cenocepacia isolate bc7, the two cultures gave different responses. while normal cultures trapped the added bacteria in the mucus layer, killed and/or inhibite ...200415213163
identification of burkholderia cenocepacia genes required for bacterial survival in vivo.burkholderia cenocepacia (formerly burkholderia cepacia complex genomovar iii) causes chronic lung infections in patients with cystic fibrosis. in this work, we used a modified signature-tagged mutagenesis (stm) strategy for the isolation of b. cenocepacia mutants that cannot survive in vivo. thirty-seven specialized plasposons, each carrying a unique oligonucleotide tag signature, were constructed and used to examine the survival of 2,627 b. cenocepacia transposon mutants, arranged in pools of ...200415213146
epidemiology of burkholderia cepacia complex species recovered from cystic fibrosis patients: issues related to patient segregation.studies of the prevalence of burkholderia cepacia complex species amongst cystic fibrosis (cf) patients in different geographical regions, and the association between cross-infection and putative transmissibility markers, will further our understanding of these organisms and help to address infection-control issues. in this study, b. cepacia complex isolates from cf patients in different regions of europe were analysed. isolates were examined for b. cepacia complex species and putative transmiss ...200415184539
burkholderia cenocepacia phage bcepmu and a family of mu-like phages encoding potential pathogenesis factors.we have isolated bcepmu, a mu-like bacteriophage whose host range includes human pathogenic burkholderia cenocepacia (formally b. cepacia genomovar iii) isolates, and determined its complete 36748 bp genomic sequence. like enteric bacteriophage mu, the bcepmu genomic dna is flanked by variable host sequences, a result of transposon-mediated replication. the bcepmu genome encodes 53 proteins, including capsid assembly components related to those of mu, and tail sheath and tube proteins related to ...200415184022
genetic characterization of a multicomponent signal transduction system controlling the expression of cable pili in burkholderia cenocepacia.cable pili are peritrichous organelles expressed by certain strains of burkholderia cenocepacia, believed to facilitate colonization of the lower respiratory tract in cystic fibrosis patients. the b. cenocepacia cblbacds operon encodes the structural and accessory proteins required for the assembly of cable pili, as well as a gene designated cbls, predicted to encode a hybrid sensor kinase protein of bacterial two-component signal transduction systems. in this study we report the identification ...200415175296
infection control and the significance of sputum and other respiratory secretions from adult patients with cystic fibrosis.there is limited data available on the environmental and public health impact of the microbiological hazards associated with sputa from patients with cystic fibrosis [cf]. pseudomonas aeruginosa, burkholderia cenocepacia (formerly burkholderia cepacia genomovar iii), staphylococcus aureus and stenotrophomonas maltophilia are bacterial pathogens which are commonly found in the sputum of cf patients. a study was performed to ascertain the amount of sputum produced relating to microbial loading, as ...200415175107
prevalence and clonality of burkholderia cepacia complex genomovars in uk patients with cystic fibrosis referred for lung transplantation.it has previously been reported that patients infected with burkholderia cenocepacia (genomovar iii) before lung transplantation have a poorer outcome than those with other b. cepacia complex infections.200415170040
virulence associated with outbreak-related strains of burkholderia cepacia complex among a cohort of patients with bacteremia.the burkholderia cepacia complex includes 9 genomovars. the relative virulence of each is unknown. host and pathogen features associated with mortality were evaluated among patients with b. cepacia complex bacteremia. cases were ascertained through review of blood culture results for the period of may 1996 through may 2002. isolates were identified to species level with 16s rdna and reca-based species-specific polymerase chain reaction analyses and reca restriction fragment-length polymorphism. ...200415127335
importance of the ornibactin and pyochelin siderophore transport systems in burkholderia cenocepacia lung infections.previously, orba, the gene encoding the outer membrane receptor for ferric-ornibactin, was identified in burkholderia cenocepacia k56-2, a strain which produces ornibactin, salicylic acid, and negligible amounts of pyochelin. a k56-2 orba mutant was less virulent than the parent strain in a rat agar bead infection model. in this study, an orba mutant of b. cenocepacia pc715j which produces pyochelin in addition to ornibactin and salicylic acid was constructed. the gene encoding the outer membran ...200415102796
conservation of the opcl gene encoding the peptidoglycan-associated outer-membrane lipoprotein among representatives of the burkholderia cepacia complex.members of the burkholderia cepacia complex are gram-negative beta-proteobacteria that are classified into nine genomic species or genomovars. some representatives of this group of bacteria, such as burkholderia multivorans (genomovar ii) and burkholderia cenocepacia (genomovar iii), are considered to be dangerous pathogens for cystic fibrosis (cf) patients because of their capacity to colonize cf lungs. the opcl gene, which encodes the peptidoglycan-associated outer-membrane lipoprotein (pal), ...200415096547
epidemiology and clinical course of burkholderia cepacia complex infections, particularly those caused by different burkholderia cenocepacia strains, among patients attending an italian cystic fibrosis center.in this study, the epidemiology of burkholderia cepacia complex (bcc) recovered from the sputum of 75 patients attending the genoa cystic fibrosis (cf) center at the gaslini children's hospital (genoa, italy) was investigated, and the clinical course of the cf patients infected with the different species and genomovars of bcc was evaluated. all isolates were analyzed for genomovar status by reca gene polymorphism and subsequently random amplified polymorphic dna fingerprinting. burkholderia ceno ...200415070994
burkholderia cenocepacia lipopolysaccharide, lipid a, and proinflammatory activity.organisms from the burkholderia cepacia complex are important pathogens in cystic fibrosis and are associated with increased rates of sepsis and death. these organisms comprise nine closely related species known as genomovars. b. cenocepacia (genomovar iii) is the most prevalent and appears the most virulent. we investigated the biological activity of a reference panel of strains using whole-cell lysates to induce septic-shock related cytokines from differentiated human monocytic cells. we found ...200415044201
the burkholderia cepacia epidemic strain marker is part of a novel genomic island encoding both virulence and metabolism-associated genes in burkholderia cenocepacia.the burkholderia cepacia epidemic strain marker (bcesm) is a useful epidemiological marker for virulent b. cenocepacia strains that infect patients with cystic fibrosis. however, there was no evidence that the original marker, identified by random amplified polymorphic dna fingerprinting, contributed to pathogenicity. here we demonstrate that the bcesm is part of a novel genomic island encoding genes linked to both virulence and metabolism. the bcesm was present on a 31.7-kb low-gc-content islan ...200414977960
transcriptional and posttranscriptional control of cable pilus gene expression in burkholderia cenocepacia.burkholderia cenocepacia is an important member of the burkholderia cepacia complex, a group of closely related bacteria that inhabits a wide variety of environmental niches in nature and that also colonizes the lungs of compromised humans. certain strains of b. cenocepacia express peritrichous adherence organelles known as cable pili, thought to be important in the colonization of the lower respiratory tract. the genetic locus required for cable pilus biogenesis is comprised of at least five ge ...200414761995
salicylate induces an antibiotic efflux pump in burkholderia cepacia complex genomovar iii (b. cenocepacia).an antibiotic efflux gene cluster that confers resistance to chloramphenicol, trimethoprim, and ciprofloxacin has been identified in burkholderia cenocepacia (genomovar iii), an important cystic fibrosis pathogen. five open reading frames have been identified in the cluster. there is apparently a single transcriptional unit, with llpe encoding a lipase-like protein, ceoa encoding a putative periplasmic linker protein, ceob encoding a putative cytoplasmic membrane protein, and opcm encoding a pre ...200414755343
isolation and characterization of burkholderia cenocepacia mutants deficient in pyochelin production: pyochelin biosynthesis is sensitive to sulfur availability.the opportunistic pathogen burkholderia cenocepacia produces the yellow-green fluorescent siderophore, pyochelin. to isolate mutants which do not produce this siderophore, we mutagenized b. cenocepacia with the transposon mini-tn5tp. two nonfluorescent mutants were identified which were unable to produce pyochelin. in both mutants, the transposon had integrated into a gene encoding an orthologue of cysw, a component of the sulfate/thiosulfate transporter. the cysw gene was located within a putat ...200414702294
the cepir quorum-sensing system contributes to the virulence of burkholderia cenocepacia respiratory infections.the cepir genes encode an n-acyl homoserine lactone (ahl)-dependent quorum-sensing system consisting of an ahl synthase that directs the synthesis of n-octanoyl-l-homoserine lactone (ohl) and n-hexanoyl-l-homoserine lactone and a transcriptional regulator. the virulence of cepir mutants was examined in two animal models. rats were infected with agar beads containing burkholderia cenocepacia k56-2, k56-i2 (cepi : : tp(r)) or k56-r2 (cepr : : tn5-ot182). at 10 days post-infection, the extent of lu ...200314663096
improved flagellin genotyping in the burkholderia cepacia complex.oligonucleotide primers designed to n- and c-terminal sequences of burkholderia cepacia complex flic genes were used to amplify and sequence flic genes from a strain of burkholderia vietnamiensis and three isolates of burkholderia multivorans with large flic genes. alignments incorporating the new sequences enabled the design of polymerase chain reaction (pcr) primers for extension of a published pcr/restriction fragment length polymorphism typing method, to include isolates that previously fail ...200314659536
adherence and autoaggregation phenotypes of a burkholderia cenocepacia cable pilus mutant.cable pili are unique peritrichous adherence organelles expressed by certain strains of the opportunistic human pathogen burkholderia cenocepacia. cable pili have been proposed to facilitate binding to human epithelial cells and mucin, and may play a role in the ability of b. cenocepacia to colonise the respiratory tract of compromised hosts. in this study, a genetic approach was undertaken to assess the role of cable pili in mediating adherence as well as bacterial cell-cell interactions. the c ...200314638436
identification and physical organization of the gene cluster involved in the biosynthesis of burkholderia cepacia complex exopolysaccharide.bacteria belonging to the burkholderia cepacia complex (bcc) are important opportunistic pathogens in patients with cystic fibrosis (cf). since approximately 80% of the cf isolates examined produce exopolysaccharide (eps), it was hypothesized that this eps may play a role in the colonization and persistence of these bacteria in the cf lung. the present study describes the identification and physical organization of the eps biosynthetic gene cluster. this bce gene cluster was identified following ...200314637140
evidence of transmission of burkholderia cepacia, burkholderia multivorans and burkholderia dolosa among persons with cystic fibrosis.previous studies have identified specific burkholderia cepacia complex strains that are common to multiple persons with cystic fibrosis (cf). such so-called epidemic strains have an apparent enhanced capacity for inter-patient spread and reside primarily in burkholderia cenocepacia (formerly b. cepacia complex genomovar iii). we sought to identify strains from b. cepacia complex species other than b. cenocepacia that are similarly shared by multiple cf patients. we performed genotype analysis of ...200314612237
in vitro activity and synergy of bismuth thiols and tobramycin against burkholderia cepacia complex.to determine the susceptibility of burkholderia multivorans and burkholderia cenocepacia to bismuth-thiols (bts), and to examine the synergistic effects of tobramycin and subinhibitory concentrations of bts against these organisms.200314585856
genomovar diversity amongst burkholderia cepacia complex isolates from an australian adult cystic fibrosis unit.in 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
polyclonal outbreak of burkholderia cepacia complex bacteraemia in haemodialysis patients.we report a polyclonal outbreak of bacteraemia involving 24 patients at a haemodialysis facility in recife (brazil). during the outbreak period (4 june to 11 july, 2001), three burkholderia cepacia complex strains were isolated from human blood and from various water samples collected at different sites in the haemodialysis unit and from dialysate fluids. out of 14 patients with positive blood cultures, six were infected by burkholderia cepacia complex bacteria: three with burkholderia cepacia g ...200312818585
identification by subtractive hybridization of a novel insertion element specific for two widespread burkholderia cepacia genomovar iii strains.species of the burkholderia cepacia complex cause chronic and life-threatening infections in persons with cystic fibrosis. epidemic strains infect multiple patients, reside primarily in genomovar iii, and have an apparent enhanced capacity for human infection and/or interpatient transmission. by using subtractive hybridization, a novel insertion element, designated is1363, was identified in epidemic strain phdc, known to infect many cystic fibrosis patients in the mid-atlantic region of the unit ...200312791867
fatal outcome of lung transplantation in cystic fibrosis patients due to small-colony variants of the burkholderia cepacia complex.the aim of this study was to investigate the possible role of small-colony variant morphotypes of burkholderia cepacia-like organisms in infectious complications in cystic fibrosis patients following lung transplantation. respiratory tract specimens from 470 cystic fibrosis patients were screened over a 22-month period for burkholderia cepacia-like organisms. nineteen patients were positive for these organisms, eight of whom harboured small-colony-variant morphotypes. three patients underwent bi ...200312687415
burkholderia cenocepacia sp. nov.--a new twist to an old story.dna-dna hybridisation experiments between isolates representing burkholderia cepacia genomovar iii reca lineages iiia and iiib reinforced the classification of both phylogenetic subgroups as a single genospecies, distinct from b. cepacia (genomovar i). a formal classification of b. cepacia genomovar iii encompassing the reca lineages iiia and iiib, and the new reca lineages iiic and iiid, as b. cenocepacia sp. nov., with lmg 16656 as the type strain, is proposed.200312648723
population structure analysis of burkholderia cepacia genomovar iii: varying degrees of genetic recombination characterize major clonal complexes.infection with bacterial species belonging to the burkholderia cepacia complex contribute significantly to morbidity and mortality in persons with cystic fibrosis (cf). the majority of isolates recovered from cf patients belong to b. cepacia genomovar iii and several distinct 'epidemic' strains have been described. this study examined the population structure of b. cepacia genomovar iii by using multilocus restriction typing, indexing allelic variation at five chromosomal genes by restriction an ...200312576582
comparative assessment of genotyping methods for epidemiologic study of burkholderia cepacia genomovar iii.we analyzed a collection of 97 well-characterized burkholderia cepacia genomovar iii isolates to evaluate multiple genomic typing systems, including pulsed-field gel electrophoresis (pfge), box-pcr fingerprinting and random amplified polymorphic dna (rapd) typing. the typeability, reproducibility, and discriminatory power of these techniques were evaluated, and the results were compared to each other and to data obtained in previous studies by using multilocus restriction typing (mlrt). all meth ...200212202570
improved molecular detection of burkholderia cepacia genomovar iii and burkholderia multivorans directly from sputum of patients with cystic fibrosis.optimum detection of the burkholderia cepacia complex (bcc) from sputum of patients with cystic fibrosis (cf) is essential in preventing patient-to-patient transmission of this organism. the aim of this study was to develop an improved pcr assay with reference to sensitivity for the direct detection of bcc organisms from cf sputum employing the reca locus. the sensitivity results of three reca pcr assays were compared using various combinations of previously published primers. these included (i) ...200211830304
endemicity and inter-city spread of burkholderia cepacia genomovar iii in cystic fibrosis.we sought to determine whether the same burkholderia cepacia complex strain has persisted as the dominant clonal lineage among patients in a large cystic fibrosis (cf) treatment center during the past 2 decades.200111713440
enhanced susceptibility to pulmonary infection with burkholderia cepacia in cftr(-/-) mice.progressive pulmonary infection is the dominant clinical feature of cystic fibrosis (cf), but the molecular basis for this susceptibility remains incompletely understood. to study this problem, we developed a model of chronic pneumonia by repeated instillation of a clinical isolate of burkholderia cepacia (genomovar iii, et12 strain), an opportunistic gram-negative bacterium, from a case of cf into the lungs of cftr (m1unc-/-) (cftr(-/-)) and congenic cftr(+/+) controls. nine days after the last ...200111447196
burkholderia cepacia genomovar iii is a common plant-associated bacterium.a polyphasic taxonomic study involving dna-dna hybridization, whole-cell protein electrophoresis, and 16s ribosomal dna sequence analysis revealed that a group of burkholderia cepacia-like organisms isolated from the rhizosphere or tissues of maize, wheat, and lupine belong to b. cepacia genomovar iii, a genomic species associated with "cepacia syndrome" in cystic fibrosis patients. the present study also revealed considerable protein electrophoretic heterogeneity within this species and demonst ...200111157274
identification of burkholderia species and genomovars from cystic fibrosis patients by aflp fingerprinting.aflp is a genomic fingerprinting technique based on the selective amplification of restriction fragments from a total double-digest of genomic dna. the applicability of this method to differentiate between species and genomovars of the genus burkholderia was tested, with particular emphasis on taxa occurring in cystic fibrosis patients. in this study, 78 well-characterized strains and field isolates were investigated by two methods of aflp fingerprinting. in the manual procedure, a radioactively ...199910555347
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