Publications

TitleAbstractYear(sorted ascending)
Filter
PMID
Filter
characterization of bcam0224, a multifunctional trimeric autotransporter from the human pathogen burkholderia cenocepacia.members of the trimeric autotransporter adhesin (taa) family play a crucial role in adhesion of gram-negative pathogens to host cells. moreover, these proteins are multifunctional virulence factors involved in several other biological traits, including invasion into host cells and evasion of the host immune system. in cystic fibrosis epidemic burkholderia cenocepacia strain j2315, we identified a unique taa (bcam0224)-encoding gene, previously described as being implicated in virulence. here, we ...201424659767
genome sequence of burkholderia cenocepacia h111, a cystic fibrosis airway isolate.the burkholderia cepacia complex (bcc) is a group of related bacterial species that are commonly isolated from environmental samples. members of the bcc can cause respiratory infections in cystic fibrosis patients and immunocompromised individuals. we report here the genome sequence of burkholderia cenocepacia h111, a well-studied model strain of the bcc.201424723723
the iclr-family regulator bapr controls biofilm formation in b. cenocepacia h111.in burkholderia cenocepacia h111, the large surface protein bapa plays a crucial role in the formation of highly structured communities, known as biofilms. we have recently demonstrated that quorum sensing (qs) is necessary for the maximal expression of bapa. in this study we identify bapr, a protein from the iclr family of transcriptional regulators that, in conjunction with qs, controls biofilm formation by affecting the expression of bapa. we present evidence that, in addition to bapa, bapr i ...201424658785
reducing virulence of the human pathogen burkholderia by altering the substrate specificity of the quorum-quenching acylase pvdq.the use of enzymes to interfere with quorum sensing represents an attractive strategy to fight bacterial infections. we used pvdq, an effective quorum-quenching enzyme from pseudomonas aeruginosa, as a template to generate an acylase able to effectively hydrolyze c8-hsl, the major communication molecule produced by the burkholderia species. we discovered that the combination of two single mutations leading to variant pvdq(lα146w,fβ24y) conferred high activity toward c8-hsl. exogenous addition of ...201424474783
broad-spectrum anti-biofilm peptide that targets a cellular stress response.bacteria form multicellular communities known as biofilms that cause two thirds of all infections and demonstrate a 10 to 1000 fold increase in adaptive resistance to conventional antibiotics. currently, there are no approved drugs that specifically target bacterial biofilms. here we identified a potent anti-biofilm peptide 1018 that worked by blocking (p)ppgpp, an important signal in biofilm development. at concentrations that did not affect planktonic growth, peptide treatment completely preve ...201424852171
the use of doripenem in pediatric cystic fibrosis patients in case of meropenem shortages.ceftazidime is the only anti-pseudomonal beta-lactam that has been reported to be administered by extended infusion in pediatric cystic fibrosis (cf) patients. a small pediatric pharmacokinetic/pharmacodynamic study has been published regarding the use of intermittent extended infusion doripenem in the treatment of an acute pulmonary exacerbation (ape) in pediatric cf patients; however, clinical use of intermittent extended infusion doripenem in pediatric cf patients has not been previously repo ...201423661625
innate immune sensing of bacterial modifications of rho gtpases by the pyrin inflammasome.cytosolic inflammasome complexes mediated by a pattern recognition receptor (prr) defend against pathogen infection by activating caspase 1. pyrin, a candidate prr, can bind to the inflammasome adaptor asc to form a caspase 1-activating complex. mutations in the pyrin-encoding gene, mefv, cause a human autoinflammatory disease known as familial mediterranean fever. despite important roles in immunity and disease, the physiological function of pyrin remains unknown. here we show that pyrin mediat ...201424919149
investigating the role of matrix components in protection of burkholderia cepacia complex biofilms against tobramycin.burkholderia cepacia complex (bcc) organisms produce a wide variety of potential virulence factors, including exopolysaccharides (eps), and exhibit intrinsic resistance towards many antibiotics. in the present study we investigated the contribution of bcc biofilm matrix components, including extracellular dna, cepacian and poly-β-1,6-n-acetylglucosamine, to tobramycin susceptibility.201423932109
pore-forming pyocin s5 utilizes the fpta ferripyochelin receptor to kill pseudomonas aeruginosa.pyocins are toxic proteins produced by some strains of pseudomonas aeruginosa that are lethal for related strains of the same species. some soluble pyocins (s2, s3 and s4) were previously shown to use the pyoverdine siderophore receptors to enter the cell. the p. aeruginosa pao1 pore-forming pyocin s5 encoding gene (pao985) was cloned into the expression vector pet15b, and the affinity-purified protein product tested for its killing activity against different p. aeruginosa strains. the results, ...201424217175
analysis of genomic characters reveals that four distinct gene clusters are correlated with different functions in burkholderia cenocepacia au 1054.possessing three circular chromosomes is a distinct genomic characteristic of burkholderia cenocepacia au 1054, a clinically important pathogen in cystic fibrosis. in this study, base composition, codon usage and functional role category were analyzed in the b. cenocepacia au 1054 genome. although no bias in the base and codon usage was detected between any two chromosomes, function differences did exist in the genes of each chromosome. similar base composition and differential functional role c ...201424305740
kinetic characterization of an oxidative, cooperative hmg-coa reductase from burkholderia cenocepacia.3-hydroxy-3-methylglutaryl coenzyme a reductase (hmgr) is a key enzyme in endogenous cholesterol biosynthesis in mammals and isoprenoid biosynthesis via the mevalonate pathway in other eukaryotes, archaea and some eubacteria. in most organisms that express this enzyme, it catalyzes the nad(p)h-dependent reduction of hmg-coa to mevalonate. we have cloned and characterized the 6x-his-tagged hmgr from the opportunistic lung pathogen burkholderia cenocepacia. kinetic characterization shows that the ...201424316250
optimization of resazurin-based viability staining for quantification of microbial biofilms.the resazurin-based viability staining is often used to quantify viable biofilm cells grown in microtiter plates (mtp). the non-fluorescent resazurin is reduced by metabolically active cells to resorufin which is fluorescent. the amount of fluorescence generated is related to the number of viable cells present. unfortunately, the linear range of the method is restricted and the lower limit of quantification is approximately 10(6) colony forming units (cfu) per biofilm. the goal of the present st ...201424365109
antimicrobial properties of an oxidizer produced by burkholderia cenocepacia p525.a compound with both oxidizing properties and antibiotic properties was extracted and purified from broth cultures of burkholderia cenocepacia strain p525. a four step purification procedure was used to increase its specific activity ~400-fold and to yield a hplc-uv chromatogram containing a single major peak. size exclusion chromatography suggests a molecular mass of ~1,150 and uv spectroscopy suggests the presence of a polyene structure consisting of as many as six conjugated double bonds. bio ...201424384626
mechanism of resistance to an antitubercular 2-thiopyridine derivative that is also active against burkholderia cenocepacia.the discovery of new compounds that are able to inhibit the growth of burkholderia cenocepacia is of primary importance for cystic fibrosis patients. here, the mechanism of resistance to a new pyridine derivative already shown to be effective against mycobacterium tuberculosis and to have good activity toward b. cenocepacia was investigated. increased expression of a resistance-nodulation-cell division (rnd) efflux system was detected in the resistant mutants, thus confirming their important rol ...201424395233
bacteria that inhibit quorum sensing decrease biofilm formation and virulence in pseudomonas aeruginosa pao1.in this study, we investigated the biotherapeutic potential of previously isolated quorum quenching (qq) bacteria. some of them produce and secrete small compounds that inhibit quorum sensing (qs), others quench qs by enzymatic degradation of n-acylhomoserine lactones (ahls). the supernatant of cultures of these isolates was tested for inhibitory properties against p. aeruginosa pao1 biofilms. most isolates had a moderate effect on biofilm formation, as shown by viability staining and/or stainin ...201424415453
respiratory infections in patients with cystic fibrosis undergoing lung transplantation.cystic fibrosis is an inherited disease characterised by chronic respiratory infections associated with bronchiectasis. lung transplantation has helped to extend the lives of patients with cystic fibrosis who have advanced lung disease. however, persistent, recurrent, and newly acquired infections can be problematic. classic cystic fibrosis-associated organisms, such as staphylococcus aureus and pseudomonas aeruginosa, are generally manageable post-transplantation, and are associated with favour ...201424461904
burkholderia dolosa phenotypic variation during the decline in lung function of a cystic fibrosis patient during 5.5 years of chronic colonization.although rarely isolated from cystic fibrosis (cf) patients, burkholderia dolosa is associated with accelerated lung function decline. during 18 years of epidemiological surveillance in the major portuguese cf centre in lisbon, only one patient was infected with b. dolosa. pulmonary deterioration, associated with the evolution of forced expiratory volume in 1 s, occurred during 5.5 years of colonization with this b. dolosa clone (with the new sequence type st-668). transient co-colonization with ...201424469681
contamination of hypertonic saline solutions in use by cystic fibrosis patients in israel.treatment of cystic fibrosis (cf) patients with inhaled hypertonic saline (hs) solutions is safe, beneficial and reduces exacerbation rates. we studied contamination of solutions used by israeli cf patients for prolonged periods.201424484849
high-resolution structure of the m14-type cytosolic carboxypeptidase from burkholderia cenocepacia refined exploiting pdb_redo strategies.a potential cytosolic metallocarboxypeptidase from burkholderia cenocepacia has been crystallized and a synchrotron-radiation microfocus beamline allowed the acquisition of diffraction data to 1.9 å resolution. the asymmetric unit comprises a tetramer containing over 1500 amino acids, and the high-throughput automated protocols embedded in pdb_redo were coupled with model-map inspections in refinement. this approach has highlighted the value of such protocols for efficient analyses. the subunit ...201424531462
identification of the flagellin glycosylation system in burkholderia cenocepacia and the contribution of glycosylated flagellin to evasion of human innate immune responses.burkholderia cenocepacia is an opportunistic pathogen threatening patients with cystic fibrosis. flagella are required for biofilm formation, as well as adhesion to and invasion of epithelial cells. recognition of flagellin via the toll-like receptor 5 (tlr5) contributes to exacerbate b. cenocepacia-induced lung epithelial inflammatory responses. in this study, we report that b. cenocepacia flagellin is glycosylated on at least 10 different sites with a single sugar, 4,6-dideoxy-4-(3-hydroxybuta ...201424841205
comparative metabolic systems analysis of pathogenic burkholderia.burkholderia cenocepacia and burkholderia multivorans are opportunistic drug-resistant pathogens that account for the majority of burkholderia cepacia complex infections in cystic fibrosis patients and also infect other immunocompromised individuals. while they share similar genetic compositions, b. cenocepacia and b. multivorans exhibit important differences in pathogenesis. we have developed reconciled genome-scale metabolic network reconstructions of b. cenocepacia j2315 and b. multivorans at ...201424163337
crystal structures of ispf from plasmodium falciparum and burkholderia cenocepacia: comparisons inform antimicrobial drug target assessment.2c-methyl-d-erythritol-2,4-cyclodiphosphate synthase (ispf) catalyzes the conversion of 4-diphosphocytidyl-2c-methyl-d-erythritol-2-phosphate to 2c-methyl-d-erythritol-2,4-cyclodiphosphate and cytidine monophosphate in production of isoprenoid-precursors via the methylerythritol phosphate biosynthetic pathway. ispf is found in the protozoan plasmodium falciparum, a parasite that causes cerebral malaria, as well as in many gram-negative bacteria such as burkholderia cenocepacia. ispf represents a ...201424410837
a burkholderia cenocepacia murj (mvin) homolog is essential for cell wall peptidoglycan synthesis and bacterial viability.the cell wall peptidoglycan (pg) of burkholderia cenocepacia, an opportunistic pathogen, has not yet been characterized. however, the b. cenocepacia genome contains homologs of genes encoding pg biosynthetic functions in other bacteria. pg biosynthesis involves the formation of the undecaprenyl-pyrophosphate-linked n-acetyl glucosamine-n-acetyl muramic acid-pentapeptide, known as lipid ii, which is built on the cytosolic face of the cell membrane. lipid ii is then translocated across the membran ...201424688094
cd4+ t cell epitopes of flic conserved between strains of burkholderia: implications for vaccines against melioidosis and cepacia complex in cystic fibrosis.burkholderia pseudomallei is the causative agent of melioidosis characterized by pneumonia and fatal septicemia and prevalent in southeast asia. related burkholderia species are strong risk factors of mortality in cystic fibrosis (cf). the b. pseudomallei flagellar protein flic is strongly seroreactive and vaccination protects challenged mice. we assessed b. pseudomallei flic peptide binding affinity to multiple hla class ii alleles and then assessed cd4 t cell immunity in hla class ii transgeni ...201425392525
retraction for ramos et al., mtvr is a global small noncoding regulatory rna in burkholderia cenocepacia.volume 195, no. 16, p. 3514–3523, 2013. a number of problems related to images published in this paper have been brought to our attention. figure 1d contains duplicated images in lanes s and le, and fig. 4d and 6b contain images previously published in articles in this journal and in microbiology and microbial pathogenesis, i.e., the following: c. g. ramos, s. a. sousa, a. m. grilo, j. r. feliciano, and j. h. leitão, j. bacteriol. 193:1515–1526, 2011. doi:10.1128/jb.01374-11. s. a. sousa, c. g. ...201425319527
retraction for ramos et al., the second rna chaperone, hfq2, is also required for survival under stress and full virulence of burkholderia cenocepacia j2315.volume 193, no. 7, p.1515–1526, 2011. problems related to images published in this paper have been brought to our attention. figure 8 contains duplicated images as well as images previously published in articles in microbiology and microbial pathogenesis, i.e., the following: s. a. sousa, c. g. ramos, l. m. moreira, and j. h. leitão, microbiology 156:896–908, 2010. http://dx.doi.org/10.1099/mic.0.035139-0. c. g. ramos, s. a. sousa, a. m. grilo, l. eberl, and j. h. leitão, microb. pathog. 48:168– ...201425319526
immunological function of familial mediterranean fever disease protein pyrin.pyrin, encoded by mefv gene, is conserved in humans and mice. mutations in the mefv gene are associated with the human autoinflammatory disease familial mediterranean fever (fmf). pyrin can interact with the inflammasome adaptor asc and induce inflammatory caspase-1 activation in monocytic cells, but the physiological function of pyrin has been unknown for many years. here we summarize previous studies of pyrin function under the context of fmf and immunity, and discuss a recent study demonstrat ...201425307949
lung transplant for a patient with cystic fibrosis and active burkholderia cenocepacia pneumonia.lung transplant for cystic fibrosis has been considered contraindicated in patients who have burkholderia cenocepacia infection. a 24-year-old white woman who had cystic fibrosis presented with respiratory failure caused by b. cenocepacia pneumonia. she was treated with broad-spectrum antibiotics and a double-lung transplant. the chest cavity and both bronchi were irrigated with 0.5% povidone-iodine solution. for immunosuppression, she received induction therapy with alemtuzumab (15 mg) and meth ...201425299375
parallel evolution of small colony variants in burkholderia cenocepacia biofilms.a common phenotype within bacterial biofilms is the small, "wrinkly" colony, which may associate with worse prognoses from biofilm-associated infections. the mechanisms that produce these variants in burkholderia are undefined. here we report the mutational and ecological causes of wrinkly (w) colonies that evolved during experimental biofilm evolution of burkholderia cenocepacia. mutations clustered in a homologous pathway to the pseudomonas wsp operon but with a distinct terminal signaling mec ...201425263109
a markerless deletion method for genetic manipulation of burkholderia cenocepacia and other multidrug-resistant gram-negative bacteria.genetic manipulation of multidrug-resistant bacteria is often difficult and hinders progress in understanding their physiology and pathogenesis. this book chapter highlights advances in genetic manipulation of burkholderia cenocepacia, which are also applicable to other members of the burkholderia cepacia complex and multidrug-resistant gram-negative bacteria of other genera. the method detailed here is based on the i-scei homing endonuclease system, which can be efficiently used for chromosomal ...201425172289
the bcesm genomic region contains a regulator involved in quorum sensing and persistence in burkholderia cenocepacia j2315.in this study, we investigated the function of bcam0257-8-9 located in the bcesm region of the burkholderia cenocepacia j2315 genome.201425156374
the attenuated virulence of a burkholderia cenocepacia paaabcde mutant is due to inhibition of quorum sensing by release of phenylacetic acid.the phenylacetic acid degradation pathway of burkholderia cenocepacia is active during cystic fibrosis-like conditions and is necessary for full pathogenicity of b. cenocepacia in nematode and rat infection models; however, the reasons for such requirements are unknown. here, we show that the attenuated virulence of a phenylacetic acid catabolism mutant is due to quorum sensing inhibition. unlike wild-type b. cenocepacia, a deletion mutant of the phenylacetyl-coa monooxygenase complex (δpaaabcde ...201425155974
ifn-γ stimulates autophagy-mediated clearance of burkholderia cenocepacia in human cystic fibrosis macrophages.burkholderia cenocepacia is a virulent pathogen that causes significant morbidity and mortality in patients with cystic fibrosis (cf), survives intracellularly in macrophages, and uniquely causes systemic infections in cf. autophagy is a physiologic process that involves engulfing non-functional organelles and proteins and delivering them for lysosomal degradation, but also plays a role in eliminating intracellular pathogens, including b. cenocepacia. autophagy is defective in cf but can be stim ...201424798083
inhibition of co-colonizing cystic fibrosis-associated pathogens by pseudomonas aeruginosa and burkholderia multivorans.cystic fibrosis (cf) is a recessive genetic disease characterized by chronic respiratory infections and inflammation causing permanent lung damage. recurrent infections are caused by gram-negative antibiotic-resistant bacterial pathogens such as pseudomonas aeruginosa, burkholderia cepacia complex (bcc) and the emerging pathogen genus pandoraea. in this study, the interactions between co-colonizing cf pathogens were investigated. both pandoraea and bcc elicited potent pro-inflammatory responses ...201424790091
evaluation of liquid and solid culture media for the recovery and enrichment of burkholderia cenocepacia from distilled water.burkholderia cepacia complex (bcc) presence has been the cause of recalls of both sterile and non-sterile pharmaceutical products since these opportunistic pathogens have been implicated to cause infections to susceptible individuals. bcc are ubiquitous in nature, but in pharmaceutical settings the most common source is contaminated water systems. some strains of bcc, previously described as pseudomonas cepacia, were not readily detected by standard culture methods. we have explored different st ...201424756630
a burkholderia cenocepacia gene encoding a non-functional tyrosine phosphatase is required for the delayed maturation of the bacteria-containing vacuoles in macrophages.burkholderia cenocepacia infects patients with cystic fibrosis. we have previously shown that b. cenocepacia can survive in macrophages within membrane vacuoles [b. cenocepacia-containing vacuoles (bccvs)] that preclude fusion with the lysosome. the bacterial factors involved in b. cenocepacia intracellular survival are not fully elucidated. we report here that deletion of bcam0628, encoding a predicted low molecular weight protein tyrosine phosphatase (lmw-ptp) that is restricted to b. cenocepa ...201424728272
involvement of toxin-antitoxin modules in burkholderia cenocepacia biofilm persistence.biofilms are involved in the recalcitrance of infections due to the presence of persister cells. although the molecular basis of persistence is still largely unknown, toxin-antitoxin modules (ta) are thought to play a role in this process. in this study, we investigated whether ta modules contribute to persistence toward antibiotics in burkholderia cenocepacia j2315. sixteen pairs of genes were identified based on their apparent similarity to ta modules. overexpression of the putative toxins had ...201424719230
a general protein o-glycosylation system within the burkholderia cepacia complex is involved in motility and virulence.bacteria of the burkholderia cepacia complex (bcc) are pathogens of humans, plants, and animals. burkholderia cenocepacia is one of the most common bcc species infecting cystic fibrosis (cf) patients and its carriage is associated with poor prognosis. in this study, we characterized a general o-linked protein glycosylation system in b. cenocepacia k56-2. the pgllbc o-oligosaccharyltransferase (o-otase), encoded by the cloned gene bcal0960, was shown to be capable of transferring a heptasaccharid ...201424673753
regulation of biofilm formation in pseudomonas and burkholderia species.in the present review, we describe and compare the molecular mechanisms that are involved in the regulation of biofilm formation by pseudomonas putida, pseudomonas fluorescens, pseudomonas aeruginosa and burkholderia cenocepacia. our current knowledge suggests that biofilm formation is regulated by cyclic diguanosine-5'-monophosphate (c-di-gmp), small rnas (srna) and quorum sensing (qs) in all these bacterial species. the systems that employ c-di-gmp as a second messenger regulate the production ...201424592823
deciphering the role of burkholderia cenocepacia membrane proteins in antimicrobial properties of chitosan.chitosan, a versatile derivative of chitin, is widely used as an antimicrobial agent either alone or mixed with other natural polymers. burkholderia cenocepacia is a multidrug-resistant bacteria and difficult to eradicate. our previous studies shown that chitosan had strong antibacterial activity against b. cenocepacia. in the current study, we have investigated the molecular aspects for the susceptibility of b. cenocepacia in response to chitosan antibacterial activity. we have conducted rna ex ...201424213809
oxidative stress in cystic fibrosis patients with burkholderia cenocepacia airway colonization: relation of 8-isoprostane concentration in exhaled breath condensate to lung function decline.the association between oxidative stress and neutrophilic inflammation in cystic fibrosis (cf) lung disease is well recognized. 8-isoprostane is a product of non-enzymatic oxidation of arachidonic acid. the aim of the present study was to examine the relationship between lung function decline and 8-isoprostane concentrations in exhaled breath condensate (ebc) in cf patients with burkholderia cenocepacia airway colonization. concentrations of 8-isoprostane in ebc were measured in 24 stable cf pat ...201424132725
protein profiling analyses of the outer membrane of burkholderia cenocepacia reveal a niche-specific proteome.outer membrane proteins (omps) are integral β-barrel proteins of the gram-negative bacterial cell wall and are crucial to bacterial survival within the macrophages and for eukaryotic cell invasion. here, we used liquid chromatography tandem mass spectrometry (lc-ms/ms) to comprehensively assess the outer membrane proteome of burkholderia cenocepacia, an opportunistic pathogen causing cystic fibrosis (cf), in conditions mimicking four major ecological niches: water, cf sputum, soil, and plant lea ...201525081413
protein engineering of a nitrilase from burkholderia cenocepacia j2315 for efficient and enantioselective production of (r)-o-chloromandelic acid.the nitrilase-mediated pathway has significant advantages in the production of optically pure aromatic α-hydroxy carboxylic acids. however, low enantioselectivity and activity are observed on hydrolyzing o-chloromandelonitrile to produce optically pure (r)-o-chloromandelic acid. in the present study, a protein engineering approach was successfully used to enhance the performance of nitrilase obtained from burkholderia cenocepacia strain j2315 (bcj2315) in hydrolyzing o-chloromandelonitrile. four ...201526431972
quantification of type vi secretion system activity in macrophages infected with burkholderia cenocepacia.the gram-negative bacterial type vi secretion system (t6ss) delivers toxins to kill or inhibit the growth of susceptible bacteria, while other secretion systems target eukaryotic cells. deletion of atsr, a negative regulator of virulence factors in b. cenocepacia k56-2, increases t6ss activity. macrophages infected with a k56-2 δatsr mutant display dramatic alterations in their actin cytoskeleton architecture that rely on the t6ss, which is responsible for the inactivation of multiple rho-family ...201526364149
survival dynamics of cystic fibrosis-related gram-negative bacterial pathogens (pseudomonas aeruginosa and burkholderia cenocepacia) in dead sea and atlantic ocean waters.clinical cystic fibrosis (cf) pseudomonas aeruginosa (n=6) and burkholderia cenocepacia (n=4) were inoculated in marine brines from the dead sea and the atlantic ocean and their survival was monitored over a 1 month duration. in dead sea samples, all p. aeruginosa and b. cenocepacia isolates were non-detectable by culture following 24 h incubation, including the non-selective enrichment samples. in the atlantic ocean brine, over a 1 month period, mean p. aeruginosa counts decreased by only 0.25 ...201526322762
efflux-mediated resistance to a benzothiadiazol derivative effective against burkholderia cenocepacia.burkholderia cenocepacia is a major concern for people suffering from cystic fibrosis as it contributes to serious respiratory tract infections. the lack of drugs effective against this opportunistic pathogen, along with the high level of resistance to multiple antibiotics, render the treatment of these infections particularly difficult. here a new compound, belonging to the 2,1,3-benzothiadiazol-5-yl family (10126109), with a bactericidal effect and a minimal inhibitory concentration (mic) of 8 ...201526300878
an electron transfer flavoprotein is essential for viability and its depletion causes a rod-to-sphere change in burkholderia cenocepacia.essential gene studies often reveal novel essential functions for genes with dispensable homologues in other species. this is the case with the widespread family of electron transfer flavoproteins (etfs), which are required for the metabolism of specific substrates or for symbiotic nitrogen fixation in some bacteria. despite these non-essential functions high-throughput screens have identified etfs as putatively essential in several species. in this study, we constructed a conditional expression ...201526253539
intracellular survival of burkholderia cepacia complex in phagocytic cells.burkholderia cepacia complex (bcc) species are a group of gram-negative opportunistic pathogens that infect the airways of cystic fibrosis patients, and occasionally they infect other immunocompromised patients. bcc bacteria display high-level multidrug resistance and chronically persist in the infected host while eliciting robust inflammatory responses. studies using macrophages, neutrophils, and dendritic cells, combined with advances in the genetic manipulation of these bacteria, have increas ...201526220706
identification of synergists that potentiate the action of polymyxin b against burkholderia cenocepacia.burkholderia cenocepacia and other members of the burkholderia cepacia complex (bcc) are highly multidrug-resistant bacteria that cause severe pulmonary infections in patients with cystic fibrosis. a screen of 2686 compounds derived from marine organisms identified molecules that could synergise with polymyxin b (pmb) to inhibit the growth of b. cenocepacia. at 1 μg/ml, five compounds synergised with pmb and inhibited the growth of b. cenocepacia by ≥70% compared with growth in pmb alone. follow ...201526187366
burkholderia cenocepacia and salmonella enterica arnt proteins that transfer 4-amino-4-deoxy-l-arabinose to lipopolysaccharide share membrane topology and functional amino acids.we recently demonstrated that incorporation of 4-amino-4-deoxy-l-arabinose (l-ara4n) to the lipid a moiety of lipopolysaccharide (lps) is required for transport of lps to the outer membrane and viability of the gram-negative bacterium burkholderia cenocepacia. arnt is a membrane protein catalyzing the transfer of l-ara4n to the lps molecule at the periplasmic face of the inner membrane, but its topology and mechanism of action are not well characterized. here, we elucidate the topology of arnt a ...201526030265
incidence of burkholderia contaminans at a cystic fibrosis centre with an unusually high representation of burkholderia cepacia during 15 years of epidemiological surveillance.the burkholderia cepacia complex (bcc) is a heterogeneous group of bacteria comprising around 20 related species. these bacteria are important opportunistic pathogens, especially in cystic fibrosis (cf) patients, and are associated with a worse prognosis and decreased life expectancy. the taxonomic position of 20 bcc isolates retrieved from cf patients receiving care at hospital santa maria (hsm), in lisbon, from 1995 to 2006, was re-examined in the present work. these isolates, formerly classif ...201526002942
the rate and molecular spectrum of spontaneous mutations in the gc-rich multichromosome genome of burkholderia cenocepacia.spontaneous mutations are ultimately essential for evolutionary change and are also the root cause of many diseases. however, until recently, both biological and technical barriers have prevented detailed analyses of mutation profiles, constraining our understanding of the mutation process to a few model organisms and leaving major gaps in our understanding of the role of genome content and structure on mutation. here, we present a genome-wide view of the molecular mutation spectrum in burkholde ...201525971664
metabolic pathways of pseudomonas aeruginosa involved in competition with respiratory bacterial pathogens.chronic airway infection by pseudomonas aeruginosa considerably contributes to lung tissue destruction and impairment of pulmonary function in cystic-fibrosis (cf) patients. complex interplays between p. aeruginosa and other co-colonizing pathogens including staphylococcus aureus, burkholderia sp., and klebsiella pneumoniae may be crucial for pathogenesis and disease progression.201525954256
enhanced xylose fermentation and ethanol production by engineered saccharomyces cerevisiae strain.we have recently demonstrated that heterologous expression of a bacterial xylose isomerase gene (xyla) of burkholderia cenocepacia enabled a laboratorial saccharomyces cerevisiae strain to ferment xylose anaerobically, without xylitol accumulation. however, the recombinant yeast fermented xylose slowly. in this study, an evolutionary engineering strategy was applied to improve xylose fermentation by the xyla-expressing yeast strain, which involved sequential batch cultivation on xylose. the resu ...201525852993
lectins from opportunistic bacteria interact with acquired variable-region glycans of surface immunoglobulin in follicular lymphoma.b-cell antigen receptor (bcr) expression is a key feature of most b-cell lymphomas, but the mechanisms of bcr signal induction and the involvement of autoantigen recognition remain unclear. in follicular lymphoma (fl) b cells, bcr expression is retained despite a chromosomal translocation that links the antiapoptotic gene bcl2 to the regulatory elements of immunoglobulin genes, thereby disrupting 1 heavy-chain allele. a remarkable feature of fl-bcrs is the acquisition of potential n-glycosylatio ...201525784678
quantification of pseudomonas aeruginosa in multispecies biofilms using pma-qpcr.multispecies biofilms are an important healthcare problem and may lead to persistent infections. these infections are difficult to treat, as cells in a biofilm are highly resistant to antimicrobial agents. while increasingly being recognized as important, the properties of multispecies biofilms remain poorly studied. in order to do so, the quantification of the individual species is needed. the current cultivation-based approaches can lead to an underestimation of the actual cell number and are ...201525755923
burkholderia cenocepacia strain ceib s5-1, a rhizosphere-inhabiting bacterium with potential in bioremediation.burkholderia cenocepacia is considered an opportunistic pathogen from humans and may cause disease in plants. a bioprospection from a plaguicide-contaminated agricultural field in mexico identified several methyl parathion-degrading bacteria. here, we report the draft genome sequence of b. cenocepacia strain ceib s5-1, which gave us clues into ecological biodiversity.201525744996
investigation of the multifaceted iron acquisition strategies of burkholderia cenocepacia.burkholderia cenocepacia is a bacterial pathogen which causes severe respiratory infections in cystic fibrosis (cf). these studies were aimed at gaining an insight into the iron acquisition strategies of b. cenocepacia. in iron restricted conditions, genes associated with the synthesis and utilisation of ornibactin (pvda, orba, orb f) were significantly upregulated compared to the expression of pyochelin associated genes (pchd, fpta). in the absence of alternative iron sources, b. cenocepacia j2 ...201525725797
search for microorganisms in men with urologic chronic pelvic pain syndrome: a culture-independent analysis in the mapp research network.we used next-generation, state-of-the-art, culture independent methodology to survey urine microbiota of males with urologic chronic pelvic pain syndrome and control participants enrolled in the mapp network to investigate a possible microbial etiology.201525596358
outcomes of intraoperative extracorporeal membrane oxygenation versus cardiopulmonary bypass for lung transplantation.the study objective was to compare the outcomes of intraoperative extracorporeal membrane oxygenation versus cardiopulmonary bypass support in lung transplantation.201525583107
characterization of a novel two-component system in burkholderia cenocepacia.two-component systems are important regulatory systems that allow bacteria to adjust to environmental conditions, and in some bacteria are used in pathogenesis. we identified a novel two-component system in burkholderia cenocepacia, an opportunistic pathogen that causes pneumonia in cystic fibrosis (cf) patients. the putative operon encodes bces, a sensor kinase, and bcer, a response regulator. our studies indicated that the bcer mutant showed a statistically significant decrease in protease, sw ...201525519693
character displacement and the evolution of niche complementarity in a model biofilm community.colonization of vacant environments may catalyze adaptive diversification and be followed by competition within the nascent community. how these interactions ultimately stabilize and affect productivity are central problems in evolutionary ecology. diversity can emerge by character displacement, in which selection favors phenotypes that exploit an alternative resource and reduce competition, or by facilitation, in which organisms change the environment and enable different genotypes or species t ...201525494960
burkholderia species infections in patients with cystic fibrosis in british columbia, canada. 30 years' experience.we have been collecting burkholderia species bacteria from patients with cystic fibrosis (cf) for the last 30 years. during this time, our understanding of their multispecies taxonomy and infection control has evolved substantially.201525474359
[the effect of introduction of the heterologous gene encoding the n-acyl-homoserine lactonase (aiia) on the properties of burkholderia cenocepacia 370].to study the role of quorum sensing (qs) regulation in the control of the cellular processes of burkholderia cenocepacia 370, plasmid pme6863 was transferred into its cells. the plasmid contains a heterologous gene encoding for aiia n-acyl-homoserine lactonase, which degrades the signaling molecules of the qs system of n-acyl-homoserine lactones (ahl). an absence or reduction of ahl in the culture was revealed with the biosensors chromobacterium violaceum cv026 and agrobacterium tumifaciens nt1/ ...201526601485
draft genome sequence of burkholderia cenocepacia strain 869t2, a plant-beneficial endophytic bacterium.an endophytic bacterium, burkholderia cenocepacia 869t2, isolated from vetiver grass, has shown its abilities for both in planta biocontrol and plant growth promotion. its draft genome sequence was determined to provide insights into those metabolic pathways involved in plant-beneficial activity. this is the first genome report for endophytic b. cenocepacia.201526564046
activation of human toll-like receptor 4 (tlr4)·myeloid differentiation factor 2 (md-2) by hypoacylated lipopolysaccharide from a clinical isolate of burkholderia cenocepacia.lung infection by burkholderia species, in particular burkholderia cenocepacia, accelerates tissue damage and increases post-lung transplant mortality in cystic fibrosis patients. host-microbe interplay largely depends on interactions between pathogen-specific molecules and innate immune receptors such as toll-like receptor 4 (tlr4), which recognizes the lipid a moiety of the bacterial lipopolysaccharide (lps). the human tlr4·myeloid differentiation factor 2 (md-2) lps receptor complex is strong ...201526160169
the effect of imipenem and diffusible signaling factors on the secretion of outer membrane vesicles and associated ax21 proteins in stenotrophomonas maltophilia.outer membrane vesicles (omvs) are small nanoscale structures that are secreted by bacteria and that can carry nucleic acids, proteins, and small metabolites. they can mediate intracellular communication and play a role in virulence. in this study, we show that treatment with the β-lactam antibiotic imipenem leads to a dramatic increase in the secretion of outer membrane vesicles in the nosocomial pathogen stenotrophomonas maltophilia. proteomic analysis of their protein content demonstrated tha ...201525926824
the host plant metabolite glucose is the precursor of diffusible signal factor (dsf) family signals in xanthomonas campestris.plant pathogen xanthomonas campestris pv. campestris produces cis-11-methyl-2-dodecenoic acid (diffusible signal factor [dsf]) as a cell-cell communication signal to regulate biofilm dispersal and virulence factor production. previous studies have demonstrated that dsf biosynthesis is dependent on the presence of rpff, an enoyl-coenzyme a (coa) hydratase, but the dsf synthetic mechanism and the influence of the host plant on dsf biosynthesis are still not clear. we show here that exogenous addit ...201525681189
burkholderia cepacia complex phage-antibiotic synergy (pas): antibiotics stimulate lytic phage activity.the burkholderia cepacia complex (bcc) is a group of at least 18 species of gram-negative opportunistic pathogens that can cause chronic lung infection in cystic fibrosis (cf) patients. bcc organisms possess high levels of innate antimicrobial resistance, and alternative therapeutic strategies are urgently needed. one proposed alternative treatment is phage therapy, the therapeutic application of bacterial viruses (or bacteriophages). recently, some phages have been observed to form larger plaqu ...201525452284
burkholderia cenocepacia infection: disruption of phagocyte immune functions through rho gtpase inactivation.phagocytosis is an important component of innate immunity that contributes to the eradication of infectious microorganisms; however, successful bacterial pathogens often evade different aspects of host immune responses. a common bacterial evasion strategy entails the production of toxins and/or effectors that disrupt normal host cell processes and because of their importance rho-family gtpases are often targeted. burkholderia cenocepacia, an opportunistic pathogen that has a propensity to infect ...201522622109
elucidation of the burkholderia cenocepacia hopanoid biosynthesis pathway uncovers functions for conserved proteins in hopanoid-producing bacteria.hopanoids are bacterial surrogates of eukaryotic membrane sterols and among earth's most abundant natural products. their molecular fossils remain in sediments spanning more than a billion years. however, hopanoid metabolism and function are not fully understood. burkholderia species are environmental opportunistic pathogens that produce hopanoids and also occupy diverse ecological niches. we investigated hopanoids biosynthesis in burkholderia cenocepacia by deletion mutagenesis and structural c ...201524888970
pseudomonas aeruginosa displays an altered phenotype in vitro when grown in the presence of mannitol.d-mannitol has been approved in dry powder formulation as an effective antimucolytic agent in patients with cystic fibrosis. what is not known is the effect of adding a metabolisable sugar on the biology of chronic bacterial pathogens in the cf lung. therefore, a series of simple in vitro experiments were performed to examine the effect of adding d-mannitol on the phenotype of the cf respiratory pathogens pseudomonas aeruginosa and burkholderia cenocepacia. clinical isolates (n = 86) consisting ...201526510267
assay development for image-based quantification of intracellular bacterial replication and analysis of the innate immune response to infection.severe bacterial infection can lead to inflammation, host tissue damage, and ultimately disseminated septic shock. the mammalian innate immune system responds to microbial infection through the detection of invariant pathogen-associated molecular patterns (pamps) by a range of pattern recognition receptors (prrs) expressed by the host cell. a successful immune response involves tightly coordinated signaling from these receptors, leading to a robust transcriptional response producing cytokines an ...201526505731
activity of tobramycin against cystic fibrosis isolates of burkholderia cepacia complex grown as biofilms.pulmonary infection with burkholderia cepacia complex in cystic fibrosis (cf) patients is associated with more-rapid lung function decline and earlier death than in cf patients without this infection. in this study, we used confocal microscopy to visualize the effects of various concentrations of tobramycin, achievable with systemic and aerosolized drug administration, on mature b. cepacia complex biofilms, both in the presence and absence of cf sputum. after 24 h of growth, biofilm thickness wa ...201526503664
clinafloxacin for treatment of burkholderia cenocepacia infection in a cystic fibrosis patient.respiratory infection with burkholderia cenocepacia is associated with accelerated decline in lung function and increased mortality in cystic fibrosis (cf) patients (a. m. jones, m. e. dodd, j. r. w. govan, v. barcus, c. j. doherty, j. morris, and a. k. webb, thorax 59:948-951, 2004, http://dx.doi.org/10.1136/thx.2003.017210). b. cenocepacia often possesses innate resistance to multiple antimicrobial classes, making eradication uncommon in established infection (p. b. davis, am j respir crit car ...201526722110
cell wall recycling-linked coregulation of ampc and penb β-lactamases through ampd mutations in burkholderia cenocepacia.in many gram-negative pathogens, mutations in the key cell wall-recycling enzyme ampd (n-acetyl-anhydromuramyl-l-alanine amidase) affect the activity of the regulator ampr, which leads to the expression of ampc β-lactamase, conferring resistance to expanded-spectrum cephalosporin antibiotics. burkholderia cepacia complex (bcc) species also have these amp homologs; however, the regulatory circuitry and the nature of causal ampd mutations remain to be explored. a total of 92 ampd mutants were obta ...201526416862
genome-wide transcription start site profiling in biofilm-grown burkholderia cenocepacia j2315.burkholderia cenocepacia is a soil-dwelling gram-negative betaproteobacterium with an important role as opportunistic pathogen in humans. infections with b. cenocepacia are very difficult to treat due to their high intrinsic resistance to most antibiotics. biofilm formation further adds to their antibiotic resistance. b. cenocepacia harbours a large, multi-replicon genome with a high gc-content, the reference genome of strain j2315 includes 7374 annotated genes. this study aims to annotate trans ...201526462475
the dsf family of cell-cell signals: an expanding class of bacterial virulence regulators.many pathogenic bacteria use cell-cell signaling systems involving the synthesis and perception of diffusible signal molecules to control virulence as a response to cell density or confinement to niches. bacteria produce signals of diverse structural classes. signal molecules of the diffusible signal factor (dsf) family are cis-2-unsaturated fatty acids. the paradigm is cis-11-methyl-2-dodecenoic acid from xanthomonas campestris pv. campestris (xcc), which controls virulence in this plant pathog ...201526181439
a pipeline for screening small molecules with growth inhibitory activity against burkholderia cenocepacia.infections with the bacteria burkholderia cepacia complex (bcc) are very difficult to eradicate in cystic fibrosis patients due the intrinsic resistance of bcc to most available antibiotics and the emergence of multiple antibiotic resistant strains during antibiotic treatment. in this work, we used a whole-cell based assay to screen a diverse collection of small molecules for growth inhibitors of a relevant strain of bcc, b. cenocepacia k56-2. the primary screen used bacterial growth in 96-well ...201526053039
burkholderia cenocepacia lipopolysaccharide modification and flagellin glycosylation affect virulence but not innate immune recognition in plants.burkholderia cenocepacia causes opportunistic infections in plants, insects, animals, and humans, suggesting that "virulence" depends on the host and its innate susceptibility to infection. we hypothesized that modifications in key bacterial molecules recognized by the innate immune system modulate host responses to b. cenocepacia. indeed, modification of lipopolysaccharide (lps) with 4-amino-4-deoxy-l-arabinose and flagellin glycosylation attenuates b. cenocepacia infection in arabidopsis thali ...201526045541
the variability of the order burkholderiales representatives in the healthcare units.the order burkholderiales became more abundant in the healthcare units since the late 1970s; it is especially dangerous for intensive care unit patients and patients with chronic lung diseases. the goal of this investigation was to reveal the real variability of the order burkholderiales representatives and to estimate their phylogenetic relationships.201526114111
σ54-dependent response to nitrogen limitation and virulence in burkholderia cenocepacia strain h111.members of the genus burkholderia are versatile bacteria capable of colonizing highly diverse environmental niches. in this study, we investigated the global response of the opportunistic pathogen burkholderia cenocepacia h111 to nitrogen limitation at the transcript and protein expression levels. in addition to a classical response to nitrogen starvation, including the activation of glutamine synthetase, pii proteins, and the two-component regulatory system ntrbc, b. cenocepacia h111 also upreg ...201525841012
in-frame and unmarked gene deletions in burkholderia cenocepacia via an allelic exchange system compatible with gateway technology.burkholderia cenocepacia is an emerging opportunistic pathogen causing life-threatening infections in immunocompromised individuals and in patients with cystic fibrosis, which are often difficult, if not impossible, to treat. understanding the genetic basis of virulence in this emerging pathogen is important for the development of novel treatment regimes. generation of deletion mutations in genes predicted to encode virulence determinants is fundamental to investigating the mechanisms of pathoge ...201525795676
efflux pump-mediated drug resistance in burkholderia.several members of the genus burkholderia are prominent pathogens. infections caused by these bacteria are difficult to treat because of significant antibiotic resistance. virtually all burkholderia species are also resistant to polymyxin, prohibiting use of drugs like colistin that are available for treatment of infections caused by most other drug resistant gram-negative bacteria. despite clinical significance and antibiotic resistance of burkholderia species, characterization of efflux pumps la ...201525926825
gene expression profiling of burkholderia cenocepacia at the time of cepacia syndrome: loss of motility as a marker of poor prognosis?cepacia syndrome (cs) is a fatal septic condition that develops in approximately 20% of cystic fibrosis (cf) patients chronically infected with the burkholderia cepacia complex (bcc). the most common causative agent is burkholderia cenocepacia, a clinically dominant bcc species that contains the globally distributed epidemic strain sequence type 32 (st32). using microarrays, we compared the transcriptomes of st32 isolates from the bloodstream at the time of cs with their sputum counterparts reco ...201525694518
there and back again: consequences of biofilm specialization under selection for dispersal.experimental evolution paired with modern sequencing can be a powerful approach to identify the mechanisms by which bacteria adapt to discrete environmental conditions found in nature or during infections. we used this approach to identify mechanisms enabling biofilm specialists of the opportunistic respiratory pathogen burkholderia cenocepacia to regain planktonic fitness. seven mutants producing wrinkly (w) small-colony variants by mutations in the wrinkly-spreader operon (wsp) cluster, but wi ...201525717335
(1)h-nmr-based endometabolome profiles of burkholderia cenocepacia clonal variants retrieved from a cystic fibrosis patient during chronic infection.during cystic fibrosis (cf) chronic lung infections, bacteria of the burkholderia cepacia complex (bcc) are exposed for several years to a stressful and changing environment. these environmental challenges results in genetic changes of the initial infecting strain with the consequent diversification of genotypes and phenotypes. the exploitation of functional and comparative genomic approaches has suggested that such diversification is associated with massive metabolic remodeling but these altera ...201628066350
biochemical characterization of glutamate racemase-a new candidate drug target against burkholderia cenocepacia infections.the greatest obstacle for the treatment of cystic fibrosis patients infected with the burkholderia species is their intrinsic antibiotic resistance. for this reason, there is a need to develop new effective compounds. glutamate racemase, an essential enzyme for the biosynthesis of the bacterial cell wall, is an excellent candidate target for the design of new antibacterial drugs. to this aim, we recombinantly produced and characterized glutamate racemase from burkholderia cenocepacia j2315. from ...201627898711
a novel method for investigating burkholderia cenocepacia infections in patients with cystic fibrosis and other chronic diseases of the airways.burkholderia cenocepacia is a gram-negative, opportunistic pathogen that is a cause of morbidity and mortality in patients with cystic fibrosis (cf). research efforts over the past few decades contributed to our understanding of these infections by identifying virulence factors. however, little is known about how this pathogen adapts to the harsh environment found inside the cf airways, which is characterized by a unique mucus containing high concentrations of inflammatory markers. the current s ...201627586172
discovery of new diketopiperazines inhibiting burkholderia cenocepacia quorum sensing in vitro and in vivo.burkholderia cenocepacia, an opportunistic respiratory pathogen particularly relevant for cystic fibrosis patients, is difficult to eradicate due to its high level of resistance to most clinically relevant antimicrobials. consequently, the discovery of new antimicrobials as well as molecules capable of inhibiting its virulence is mandatory. in this regard quorum sensing (qs) represents a good target for anti-virulence therapies, as it has been linked to biofilm formation and is important for the ...201627580679
candidate essential genes in burkholderia cenocepacia j2315 identified by genome-wide tradis.burkholderia cenocepacia infection often leads to fatal cepacia syndrome in cystic fibrosis patients. however, antibiotic therapy rarely results in complete eradication of the pathogen due to its intrinsic resistance to many clinically available antibiotics. recent attention has turned to the identification of essential genes as the proteins encoded by these genes may serve as potential targets for development of novel antimicrobials. in this study, we utilized tradis (transposon directed insert ...201627597847
the role of reactive oxygen species in antibiotic-induced cell death in burkholderia cepacia complex bacteria.it was recently proposed that bactericidal antibiotics, besides through specific drug-target interactions, kill bacteria by a common mechanism involving the production of reactive oxygen species (ros). however, this mechanism involving the production of hydroxyl radicals has become the subject of a lot of debate. since the contribution of ros to antibiotic mediated killing most likely depends on the conditions, differences in experimental procedures are expected to be at the basis of the conflic ...201627438061
the burkholderia cenocepacia ompa-like protein bcal2958: identification, characterization, and detection of anti-bcal2958 antibodies in serum from b. cepacia complex-infected cystic fibrosis patients.respiratory infections by bacteria of the burkholderia cepacia complex (bcc) remain an important cause of morbidity and mortality among cystic fibrosis patients, highlighting the need for novel therapeutic strategies. in the present work we have studied the b. cenocepacia protein bcal2958, a member of the ompa-like family of proteins, demonstrated as highly immunogenic in other pathogens and capable of eliciting strong host immune responses. the encoding gene was cloned and the protein, produced ...201627325348
synthetic cystic fibrosis sputum medium regulates flagellar biosynthesis through the flhf gene in burkholderia cenocepacia.burkholderia cenocepacia belongs to the burkholderia cepacia complex (bcc), a group of at least 18 distinct species that establish chronic infections in the lung of people with the genetic disease cystic fibrosis (cf). the sputum of cf patients is rich in amino acids and was previously shown to increase flagellar gene expression in b. cenocepacia. we examined flagellin expression and flagellar morphology of b. cenocepacia grown in synthetic cystic fibrosis sputum medium (scfm) compared to minima ...201627379216
cyanide toxicity to burkholderia cenocepacia is modulated by polymicrobial communities and environmental factors.microbes within polymicrobial communities can establish positive and negative interactions that have the potential to influence the overall behavior of the community. pseudomonas aeruginosa and species of the burkholderia cepacia complex (bcc) can co-exist in the lower airways, however several studies have shown that p. aeruginosa can effectively kill the bcc in vitro, for which hydrogen cyanide (hcn) was recently proposed to play a critical role. here we show that modification of the environmen ...201627242743
structural features essential to the antimicrobial functions of human splunc1.splunc1 is an abundantly secreted innate immune protein in the mammalian respiratory tract that exerts bacteriostatic and antibiofilm effects, binds to lipopolysaccharide (lps), and acts as a fluid-spreading surfactant. here, we unravel the structural elements essential for the surfactant and antimicrobial functions of human splunc1 (short palate lung nasal epithelial clone 1). a unique α-helix (α4) that extends from the body of splunc1 is required for the bacteriostatic, surfactant, and lps bin ...201627145151
draft genome sequence of burkholderia cenocepacia strain ceib s5-2, a methyl parathion- and p-nitrophenol-degrading bacterium, isolated from agricultural soils in morelos, mexico.burkholderia cenocepacia is an opportunistic pathogen that belongs to burkholderia cepacia complex (bcc). burkholderia cenocepacia strain ceib s5-2 was isolated from agricultural soils in morelos, mexico, and previously has shown its abilities for bioremediation. in this study, we report the draft genome sequence of burkholderia cenocepacia strain ceib s5-2.201627125479
linocin and ompw are involved in attachment of the cystic fibrosis-associated pathogen burkholderia cepacia complex to lung epithelial cells and protect mice against infection.members of the burkholderia cepacia complex (bcc) cause chronic opportunistic lung infections in people with cystic fibrosis (cf), resulting in a gradual lung function decline and, ultimately, patient death. the bcc is a complex of 20 species and is rarely eradicated once a patient is colonized; therefore, vaccination may represent a better therapeutic option. we developed a new proteomics approach to identify bacterial proteins that are involved in the attachment of bcc bacteria to lung epithel ...201626902727
tyrosine phosphorylation and dephosphorylation in burkholderia cenocepacia affect biofilm formation, growth under nutritional deprivation, and pathogenicity.burkholderia cenocepacia, a member of the b. cepacia complex (bcc), is an opportunistic pathogen causing serious chronic infections in patients with cystic fibrosis. tyrosine phosphorylation has emerged as an important posttranslational modification modulating the physiology and pathogenicity of bcc bacteria. here, we investigated the predicted bacterial tyrosine kinases bcam1331 and bcef and the low-molecular-weight protein tyrosine phosphatases bcam0208, bced, and bcal2200 of b. cenocepacia k5 ...201626590274
polyphasic characterisation of burkholderia cepaciacomplex species isolated from children with cystic fibrosis.cystic fibrosis (cf) patients with burkholderia cepacia complex (bcc) pulmonary infections have high morbidity and mortality. the aim of this study was to compare different methods for identification of bcc species isolated from paediatric cf patients. oropharyngeal swabs from children with cf were used to obtain isolates of bcc samples to evaluate six different tests for strain identification. conventional (cpt) and automatised (apt) phenotypic tests, polymerase chain reaction (pcr)-reca, restr ...201626814642
Displaying items 401 - 500 of 549