Project description:Transcriptional profiling of RNA-seq data from two Burkholderia species grown under conditions mimicking the cystic fibrosis lung and the soil environment
Project description:An important, but rarely performed, test of Koch’s molecular postulates involves evaluating the capacity of candidate virulence genes to confer pathogenicity in otherwise non-virulent species. Unbiased genomic surveys of avirulent natural isolates might reveal rare variants possessing specific virulence features, which might prove useful in testing their functional sufficiency. Using a custom pan-genome array, we analyzed a panel of avirulent Burkholderia thailandensis (Bt) isolates related to Burkholderia pseudomallei (Bp), the causative agent of the often fatal human and animal disease melioidosis. We report the discovery of variant Bt isolates exhibiting isolated acquisition of a capsular polysaccharide biosynthesis gene cluster (BpCPS), long regarded as an critical species-specific virulence factor essential for Bp mammalian virulence. BpCPS-expressing Bt strains exhibited certain pathogen-related phenotypes including resistance to human complement binding, but did not exhibit enhanced virulence when assessed in two different in vivo animal infection models. Phylogenetic analysis revealed that the BpCPS-expressing Bt strains likely reside within an evolutionary subgroup distinct from the majority of previously-described Bt strains. Our findings suggest that BpCPS acquisition alone is unlikely to fully explain the ability of Bp to colonize humans and animals, highlighting the importance of other collaborating factors in the pathogenesis of mammalian melioidosis.
Project description:Burkholderia cepacia complex (Bcc) comprises opportunistic bacteria infecting hosts such as cystic fibrosis (CF) patients. Bcc long-term infection of CF patient airways has been associated with emergence of phenotypic variation. Here we studied two Burkholderia multivorans clonal isolates (D2095 and D2214) displaying different morphotypes from a chronically infected CF patient in order to evaluate traits development during lung infection. Since the custom array described in platform GPL13356 was based on Burkholderia multivorans ATCC 17616 genome, here we performed a DNA-DNA hybridization to determine which probes of the array hybridize with our test genomes
Project description:Gene expression profiles of human cell (THP-1) lines exposed to a novel Daboiatoxin (DbTx) isolated from Daboia russelli russelli, and specific cytokines and inflammatory pathways involved in acute infection caused by Burkholderia pseudomallei. Keywords: Melioidosis, Burkholderia pseudomallei, Daboiatoxin, Cytokines, Inflammation.
Project description:An important, but rarely performed, test of Koch’s molecular postulates involves evaluating the capacity of candidate virulence genes to confer pathogenicity in otherwise non-virulent species. Unbiased genomic surveys of avirulent natural isolates might reveal rare variants possessing specific virulence features, which might prove useful in testing their functional sufficiency. Using a custom pan-genome array, we analyzed a panel of avirulent Burkholderia thailandensis (Bt) isolates related to Burkholderia pseudomallei (Bp), the causative agent of the often fatal human and animal disease melioidosis. We report the discovery of variant Bt isolates exhibiting isolated acquisition of a capsular polysaccharide biosynthesis gene cluster (BpCPS), long regarded as an critical species-specific virulence factor essential for Bp mammalian virulence. BpCPS-expressing Bt strains exhibited certain pathogen-related phenotypes including resistance to human complement binding, but did not exhibit enhanced virulence when assessed in two different in vivo animal infection models. Phylogenetic analysis revealed that the BpCPS-expressing Bt strains likely reside within an evolutionary subgroup distinct from the majority of previously-described Bt strains. Our findings suggest that BpCPS acquisition alone is unlikely to fully explain the ability of Bp to colonize humans and animals, highlighting the importance of other collaborating factors in the pathogenesis of mammalian melioidosis. Genomic DNA of several Bt strains were hybridized against a common reference strain (Bt E264), to see gain/loss
Project description:[1] Transcription profiling of one Burkholderia cenocepacia clinical isolate, J2315, versus a soil isolate, HI2424, in conditions mimicking CF sputum [2] Transcription profiling of Burkholderia cenocepacia isolates J2315 and HI2424 in media mimicking CF sputum or the soil environment
