Project description:Investigation of whole genome gene expression level changes in a Vibrio cholerae O395N1 delta-nqrA-F mutant, compared to the wild-type strain. Total RNA recovered from wild-type cultures of VIbrio cholerae O395N1 and its nqrA-F mutant strain. Each chip measures the expression level of 3,835 genes from Vibrio cholerae O1 biovar eltor str. N16961 with twenty average probes/gene, with five-fold technical redundancy.
Project description:Antibodies targeting the O-specific polysaccharide (OSP) of Vibrio cholerae O1 are a main determinant of protection against cholera. These antibodies can agglutinate bacteria, and can also directly inhibit V. cholerae motility, including at sub-agglutinating conditions. In order to evaluate for possible additional impacts of OSP-specific antibody on V. cholerae, we assessed the transcriptional profile of V. cholerae exposed to an anti-OSP human monoclonal antibody (G1), including in the presence of mucin, the principal component of intestinal mucous. We identified a subset of genes whose expression was significantly altered in the presence of anti-OSP antibody and mucin, including those involved in V. cholerae metabolism, transport, stress response, biofilm formation, motility, and secondary messenger signaling. Our results suggest a broad impact of anti-OSP antibodies on V. cholerae in the presence of mucin and identify several possible mechanisms by which anti-OSP antibodies might protect against cholera.
Project description:Investigation of whole genome gene expression level changes in a Vibrio cholerae O395N1 delta-nqrA-F mutant, compared to the wild-type strain.
Project description:These experiments were performed to show serogroup conversion in Vibrio cholerae from O1 to O139 in a mixed communities / biofilms. For this purpose, V. cholerae O1 El Tor A1552 and VCO139-Kan strain (a MO10 derivative; O139 serogroup) were grown on crab shell fragments to induce natural competence for transformation. Transformants were selected on LB+Kan+Rif plates. O139 positive transformants have undergone a full exchange of the O1 region by the O139 region. This implies an exchange of an at least 32 kb spanning O1 genomic region by more than 42 kb of the O139 region. The transformation experiment was done at least five independent times; data from four experiments are shown; per experiment one to three clones were analysed by CGH with two experimental replicates each.
