Project description:In this study, we determined the TfoY regulon of V. cholerae using RNA-seq to better uderstand the protein's function. mRNA profiles of a WT V. cholerae O1 El Tor strain (A1552) and of a TfoY-producing derivative of the WT strain (A1552-TntfoY). 3 independent biological replicates are provided for each bacterial strain. The bacteria were grown to high cell density and in the presence of arabinose (to induce TfoY in strain A1552-TntfoY).
Project description:In this study, we determined the expression profile of V. cholerae strain A1552 and its varA-deficient mutant at two different growth stages (OD600 of 0.2 or 2.5)
Project description:In this study, we determined the TfoX regulon of V. cholerae WT strain A1552 compared to a ΔhapR and ΔqstR strain using RNA-seq to better understand the protein's function.
Project description:In this study, we compared the QstR regulon to the TfoX regulon (and TfoY regulon) of V. cholerae in WT strain A1552 and its ΔhapRΔvpsA derivative using RNA-seq to better understand QstR's function.
Project description:We identified the mutated gene locus in a pigment overproducing Vibrio cholerae mutant of strain A1552. The deduced gene product is suggested to be a oxidoreductase based on partial homology to putative homogentisate 1,2-dioxygenase in Pseudomonas aeruginosa and Mesorhizobium loti and we propose that the gene VC1345 in the V. cholerae genome be denoted hmgA in accordance with the nomenclature for other species. The hmgA::miniTn5 mutant showed a non-pigmented phenotype after complementation with a plasmid clone carrying the wild type hmgA+ locus. Microarray transcription analysis revealed that expression of hmgA, and the neighboring genes encoding a postulated two component sensor system, was growth phase dependent. Results from qRT-PCR analysis showed that hmgA operon expression was reduced in the rpoS mutant, but pigment production by the wild type V. cholerae or the hmgA mutant was not detectably influenced by the stationary phase regulator RpoS. The pigmented mutant showed increased UV resistance in comparison with the wild-type strain. Interestingly, the pigment producing mutant expressed more toxin co-regulated pili and cholera toxin in comparison with wild type V. cholerae. Moreover, the hmgA mutant showed a 5-fold increase in the ability to colonize the intestines of infant mice. A possible mechanism by which pigment production might cause induction of the ToxR regulon due to generation of hydrogen peroxide was supported by results from tests showing that externally supplied H2O2 led to higher TcpA levels. Taken together, our findings suggest that melanin pigment formation may play a role in V. cholerae virulence factor expression. Groups of assays that are related as part of a time series. Elapsed Time: Wild type V. cholerae strain A1552 bacteria were cultured statically for 4 h in AKI medium at 37C and then shifted to aerobic growth for 6 h using shaken culture flasks. Samples were taken at hourly during the this process. Keywords: time_series_design Using regression correlation
Project description:We identified the mutated gene locus in a pigment overproducing Vibrio cholerae mutant of strain A1552. The deduced gene product is suggested to be a oxidoreductase based on partial homology to putative homogentisate 1,2-dioxygenase in Pseudomonas aeruginosa and Mesorhizobium loti and we propose that the gene VC1345 in the V. cholerae genome be denoted hmgA in accordance with the nomenclature for other species. The hmgA::miniTn5 mutant showed a non-pigmented phenotype after complementation with a plasmid clone carrying the wild type hmgA+ locus. Microarray transcription analysis revealed that expression of hmgA, and the neighboring genes encoding a postulated two component sensor system, was growth phase dependent. Results from qRT-PCR analysis showed that hmgA operon expression was reduced in the rpoS mutant, but pigment production by the wild type V. cholerae or the hmgA mutant was not detectably influenced by the stationary phase regulator RpoS. The pigmented mutant showed increased UV resistance in comparison with the wild-type strain. Interestingly, the pigment producing mutant expressed more toxin co-regulated pili and cholera toxin in comparison with wild type V. cholerae. Moreover, the hmgA mutant showed a 5-fold increase in the ability to colonize the intestines of infant mice. A possible mechanism by which pigment production might cause induction of the ToxR regulon due to generation of hydrogen peroxide was supported by results from tests showing that externally supplied H2O2 led to higher TcpA levels. Taken together, our findings suggest that melanin pigment formation may play a role in V. cholerae virulence factor expression. Groups of assays that are related as part of a time series. Elapsed Time: Wild type V. cholerae strain A1552 bacteria were cultured statically for 4 h in AKI medium at 37C and then shifted to aerobic growth for 6 h using shaken culture flasks. Samples were taken at hourly during the this process. Keywords: time_series_design
Project description:In this study, we determined the expression of V. cholerae strain A1552 and its SNP45-converted derivative as well as the expression of strain ATCC25872 and its SNP45-converted derivative.