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:We exposed wild-type Vibrio cholerae E7496, multiple Vibrio cholerae virulence factor deleted genes with intact hemolysin A gene [CVD109] and without hemolysin A gene [CVD110] in E7946, and E.coli OP50 to wild-type C.elegans N2 for 18 hours. We used microarrays to detail the global gene expression and identified distinct classes of up-regulated and down-regulated genes during this process. C. elegans were exposed to Vibrio cholerae and E.coli then hybridization on Affymetrix microarray chips.
Project description:We used RNA-seq to determine transcriptional profiles of whole guts or IPCs isolated from guts infected with wild type or type VI secretion system deficient Vibrio cholerae. We found significant differences between guts and progenitor cells infected wild type or type VI secretion system deficient Vibrio cholerae.
Project description:Horizontally acquired genetic elements (HGEs) plays a major for determination of virulence, antimicrobial resistance, adaptation and evolution in pathogenic bacteria. Conserved integrative mobile genetic elements (MGEs) of Vibrio cholerae contribute in the disease development, antimicrobial resistance and metabolic functions. To understand the dynamics of integrative MGEs and cross talk between MGEs and core genome, engineered genome of V. cholerae was monitored in the presence and absence of horizontally acquired genetic elements. Deletion of more than 250 revealed that CTX contributes to the essentiality of SOS response master regulator LexA in V. cholerae. Also, he core genome encoded RecA helps CTX to bypass the host immunity and replicate in the host cell in the presence of similar prophage in the host chromosome. Finally, our multiomics data reveal importance of MGEs in modulating the level of cellular proteome and metabolome in V. cholerae. This study for the first time engineered the genome of V. cholerae strains to eliminate all the GIs, ICE and prophages from their genome and revealed new interactions between core and acquired genomes. The engineered strain could be a potential candidate for understanding evolution of cholera pathogen and development of therapeutics.
Project description:We exposed wild-type Vibrio cholerae E7496, multiple Vibrio cholerae virulence factor deleted genes with intact hemolysin A gene [CVD109] and without hemolysin A gene [CVD110] in E7946, and E.coli OP50 to wild-type C.elegans N2 for 18 hours. We used microarrays to detail the global gene expression and identified distinct classes of up-regulated and down-regulated genes during this process.
Project description:DNA methylation is a key epigenetic regulator in all domains of life, yet the effects of most bacterial DNA methyltransferases on cellular processes are largely undefined. Here, we used diverse techniques, including bisulfite sequencing, transcriptomics, and transposon insertion site sequencing to extensively characterize a 5-methylcytosine (5mC) methyltransferase, VchM, in the cholera pathogen, Vibrio cholerae. We have comprehensively defined VchM's DNA targets, its genetic interactions and the gene networks that it regulates. Although VchM is a relatively new component of the V. cholerae genome, it is required for optimal V. cholerae growth in vitro and during infection. Unexpectedly, the usually essential ÏE cell envelope stress pathway is dispensable in ÎvchM V. cholerae, likely due to its lower activation in this mutant and the capacity for VchM methylation to limit expression of some cell envelope modifying genes. Our work illuminates how an acquired DNA methyltransferase can become integrated within complex cell circuits to control critical housekeeping processes. Duplicates samples were analyzed for wildtype cells grown under 3 conditions: exponential phase, stationary phase and rabbit intestinal infection
Project description:Pandemic and endemic strains of Vibrio cholerae arise from toxigenic conversion by the CTXφ bacteriophage, a process by which CTXφ infects non-toxigenic strains of V. cholerae. CTXφ encodes the cholera toxin, an enterotoxin responsible for the watery diarrhea associated with cholera infections. Despite the critical role of CTXφ during infections, signals that affect CTXφ-driven toxigenic conversion or expression of the CTXφ-encoded cholera toxin remain poorly characterized, particularly in the context of the gut mucosa. Here, we identify mucin polymers as potent regulators of CTXφ-driven pathogenicity in V. cholerae. Our results indicate that mucin-associated O-glycans block toxigenic conversion by CTXφ and suppress the expression of CTXφ-related virulence factors, including the toxin co-regulated pilus and cholera toxin, by interfering with the TcpP/ToxR/ToxT virulence pathway. By synthesizing individual mucin glycan structures de novo, we identify the Core 2 motif as the critical structure governing this virulence attenuation. Overall, our results highlight a novel mechanism by which mucins and their associated O-glycan structures affect CTXφ-mediated evolution and pathogenicity of V. cholerae, underscoring the potential regulatory power housed within mucus.
