Conservation of the opcL gene encoding the peptidoglycan-associated outer-membrane lipoprotein among representatives of the Burkholderia cepacia complex

2004 ◽  
Vol 53 (5) ◽  
pp. 389-398 ◽  
Author(s):  
Maria Plesa ◽  
Abdelaziz Kholti ◽  
Karen Vermis ◽  
Peter Vandamme ◽  
Stavroula Panagea ◽  
...  
Keyword(s):  
Outer Membrane ◽  
Burkholderia Cepacia ◽  
Sequence Data ◽  
Burkholderia Cenocepacia ◽  
Burkholderia Cepacia Complex ◽  
Gene Encoding ◽  
Burkholderia Multivorans ◽  
Outer Membrane Lipoprotein ◽  
Membrane Lipoprotein ◽  
High Degree

Members of the Burkholderia cepacia complex are Gram-negative β-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), was detected in the genome of Burkholderia sp. LB 400 by a similarity search that was based on the sequence of the Pseudomonas aeruginosa PAL, OprL. Primers that could amplify part of opcL from B. multivorans LMG 13010T were designed. This PCR fragment was used as a probe for screening of a B. multivorans genomic bank, allowing cloning of the complete opcL gene. The complete opcL gene could be PCR-amplified from DNA from all genomovars. The sequences of these opcL genes showed a high degree of conservation (> 95 %) among different species of the B. cepacia complex. OpcL protein that was purified from B. multivorans LMG 13010T was used to generate mouse polyclonal antisera against OpcL. The OpcL protein could be produced in Escherichia coli and detected in outer-membrane fractions by Western blot. Burkholderia cells were labelled by immunofluorescence staining using antibodies against OpcL, but only after treatment with EDTA and SDS. The opcL gene could be amplified directly from the sputa of 15 CF patients who were known to be colonized by B. cepacia; sequence data derived from the amplicons identified the colonizing strains as B. cenocepacia (genomovar III, n = 14) and B. multivorans (n = 1).

The SlyB outer membrane lipoprotein of Burkholderia multivorans contributes to membrane integrity

2006 ◽  
Vol 157 (6) ◽  
pp. 582-592 ◽  
Author(s):  
Maria Plesa ◽  
Jean-Pierre Hernalsteens ◽  
Guy Vandenbussche ◽  
Jean-Marie Ruysschaert ◽  
Pierre Cornelis
Keyword(s):  
Outer Membrane ◽  
Membrane Integrity ◽  
Burkholderia Multivorans ◽  
Outer Membrane Lipoprotein ◽  
Membrane Lipoprotein

Approaches to measure the fitness of Burkholderia cepacia complex isolates

2010 ◽  
Vol 59 (6) ◽  
pp. 679-686 ◽  
Author(s):  
C. F. Pope ◽  
S. H. Gillespie ◽  
J. E. Moore ◽  
T. D. McHugh
Keyword(s):  
Growth Rate ◽  
Biofilm Formation ◽  
Burkholderia Cepacia ◽  
Antibacterial Agents ◽  
Burkholderia Cenocepacia ◽  
Burkholderia Cepacia Complex ◽  
Growth And Survival ◽  
Burkholderia Multivorans ◽  
Biologically Relevant

Members of the Burkholderia cepacia complex (Bcc) are highly resistant to many antibacterial agents and infection can be difficult to eradicate. A coordinated approach has been used to measure the fitness of Bcc bacteria isolated from cystic fibrosis (CF) patients with chronic Bcc infection using methods relevant to Bcc growth and survival conditions. Significant differences in growth rate were observed among isolates; slower growth rates were associated with isolates that exhibited higher MICs and were resistant to more antimicrobial classes. The nucleotide sequences of the quinolone resistance-determining region of gyrA in the isolates were determined and the ciprofloxacin MIC correlated with amino acid substitutions at codons 83 and 87. Biologically relevant methods for fitness measurement were developed and could be applied to investigate larger numbers of clinical isolates. These methods were determination of planktonic growth rate, biofilm formation, survival in water and survival during drying. We also describe a method to determine mutation rate in Bcc bacteria. Unlike in Pseudomonas aeruginosa where hypermutability has been detected in strains isolated from CF patients, we were unable to demonstrate hypermutability in this panel of Burkholderia cenocepacia and Burkholderia multivorans isolates.

Epidemiology of Burkholderia cepacia complex species recovered from cystic fibrosis patients: issues related to patient segregation

2004 ◽  
Vol 53 (7) ◽  
pp. 663-668 ◽  
Author(s):  
Andrew McDowell ◽  
Eshwar Mahenthiralingam ◽  
Kerstin E.A. Dunbar ◽  
John E. Moore ◽  
Mary Crowe ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Burkholderia Cepacia ◽  
Cross Infection ◽  
Burkholderia Cenocepacia ◽  
Burkholderia Cepacia Complex ◽  
Complex Species ◽  
Burkholderia Multivorans ◽  
Burkholderia Vietnamiensis ◽  
Random Amplification ◽  
Geographical Regions

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 transmissibility markers [cable pilin subunit gene (cblA) and the B. cepacia epidemic strain marker (BCESM)]. Sporadic and cross-infective strains were identified by random amplification of polymorphic DNA (RAPD). In total, 79 % of patients were infected with Burkholderia cenocepacia (genomovar III), 18 % with Burkholderia multivorans (genomovar II) and less than 5 % of patients with B. cepacia (genomovar I), Burkholderia stabilis (genomovar IV) or Burkholderia vietnamiensis (genomovar V). The cblA and BCESM transmissibility markers were only detected in strains of B. cenocepacia. The BCESM was a more sensitive marker for transmissible B. cenocepacia strains than cblA, although sporadic B. cenocepacia strains containing the BCESM, but lacking cblA, were also observed. Furthermore, clusters of cross-infection with transmissibility marker-negative strains of B. multivorans were identified. In conclusion, B. cenocepacia was the greatest cause of cross-infection, and the most widely distributed B. cepacia complex species, within these CF populations. However, cross-infection was not exclusive to B. cenocepacia and cblA and the BCESM were not absolute markers for transmissible B. cenocepacia, or other B. cepacia complex strains. It is therefore suggested that CF centres cohort patients based on the presence or absence of B. cepacia complex infection and not on the basis of transmissibility marker-positive B. cenocepacia as previously suggested.

scholarly journals GVF27, a human derived peptide with anti-infective properties against biofilm forming members of the Burkholderia cepacia complex

2021 ◽  
Author(s):  
Andrea Bosso ◽  
Rosa Gaglione ◽  
Rocco Di Girolamo ◽  
Edwin Veldhuizen ◽  
Pilar García-Vello ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Burkholderia Cepacia ◽  
Therapeutic Agent ◽  
Burkholderia Cenocepacia ◽  
Burkholderia Cepacia Complex ◽  
Human Monocytes ◽  
Burkholderia Multivorans ◽  
Bacterial Cultures ◽  
High Level ◽  
Pro Inflammatory Cytokines

Abstract Therapeutic solutions to counter Burkholderia cepacia complex (Bcc) bacteria are challenging due to their intrinsically high level of antibiotic resistance. Bcc organisms display a variety of potential virulence factors, have a distinct lipopolysaccharide naturally implicated in antimicrobial resistance and are able to form biofilms, which may further protect them from both host defence peptides (HDPs) and antibiotics. Here, we report the extremely promising anti-biofilm and immunomodulatory activities of human HDP GVF27 on two of the most clinically relevant Bcc members, as Burkholderia multivorans and Burkholderia cenocepacia. The effects of synthetic and labelled GVF27 were tested on B. cenocepacia and B. multivorans biofilms, at three different stages of formation, by alternative microscopy approaches. Assays on bacterial cultures and on human monocytes challenged with B. cenocepacia LPS, were also performed. GVF27 exerts, at different stages of formation, meaningful anti-biofilm effects towards both Bcc strains, a significant propensity to function in combination with ciprofloxacin, a relevant affinity for LPSs isolated from Burkholderia cenocepacia as well as a good propensity to mitigate the release of pro-inflammatory cytokines in human cells pre-treated with the same endotoxin. Overall, all these findings contribute to the elucidation of the main features that a good therapeutic agent directed against these extremely leathery biofilm-forming bacteria should possess.

scholarly journals Evaluation of the electron transfer flavoprotein as an antibacterial target in Burkholderia cenocepacia

2017 ◽  
Vol 63 (10) ◽  
pp. 857-863 ◽  
Author(s):  
Maria S. Stietz ◽  
Christina Lopez ◽  
Osasumwen Osifo ◽  
Marcelo E. Tolmasky ◽  
Silvia T. Cardona
Keyword(s):  
Electron Transfer ◽  
Burkholderia Cepacia ◽  
Multidrug Resistant ◽  
Burkholderia Cenocepacia ◽  
Burkholderia Cepacia Complex ◽  
Infection Model ◽  
Electron Transfer Flavoprotein ◽  
C Elegans

There are hundreds of essential genes in multidrug-resistant bacterial genomes, but only a few of their products are exploited as antibacterial targets. An example is the electron transfer flavoprotein (ETF), which is required for growth and viability in Burkholderia cenocepacia. Here, we evaluated ETF as an antibiotic target for Burkholderia cepacia complex (Bcc). Depletion of the bacterial ETF during infection of Caenorhabditis elegans significantly extended survival of the nematodes, proving that ETF is essential for survival of B. cenocepacia in this host model. In spite of the arrest in respiration in ETF mutants, the inhibition of etf expression did not increase the formation of persister cells, when treated with high doses of ciprofloxacin or meropenem. To test if etf translation could be inhibited by RNA interference, antisense oligonucleotides that target the etfBA operon were synthesized. One antisense oligonucleotide was effective in inhibiting etfB translation in vitro but not in vivo, highlighting the challenge of reduced membrane permeability for the design of drugs against B. cenocepacia. This work contributes to the validation of ETF of B. cenocepacia as a target for antibacterial therapy and demonstrates the utility of a C. elegans liquid killing assay to validate gene essentiality in an in vivo infection model.

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