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.
2020-09-28 | PXD017801 | Pride
Project description:Within-patient evolution of Vibrio cholerae
Project description:Understanding gene expression by bacteria during the actual course of human infection may provide important insights into microbial pathogenesis. In this study, we evaluated the transcriptional profile of Vibrio cholerae, the causative agent of cholera, in clinical specimens from cholera patients. We collected samples of human stool and vomitus that were positive by dark-field microscopy for abundant vibrios and used a microarray to compare gene expression in organisms recovered directly from the early and late stages of human infection. Our results reveal that V. cholerae gene expression within the human host environment differs from patterns defined in in vitro models of pathogenesis. tcpA, the major subunit of the essential V. cholerae colonization factor, was significantly more highly expressed in early compared with late infection; however, the genes encoding cholera toxin were not highly expressed in either phase of human infection. Furthermore, expression of the virulence regulators, toxRS and tcpPH, was uncoupled. Interestingly, the pattern of gene expression indicates that the human upper intestine may be a uniquely suitable environment for the transfer of genetic elements that are important in the evolution of pathogenic strains of V. cholerae. These findings provide a more detailed assessment of the transcriptome of V. cholerae in the human host than previous studies of organisms in stool alone and have implications for cholera control and the design of improved vaccines. Keywords: comparative gene expression analysis
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:Understanding gene expression by bacteria during the actual course of human infection may provide important insights into microbial pathogenesis. In this study, we evaluated the transcriptional profile of Vibrio cholerae, the causative agent of cholera, in clinical specimens from cholera patients. We collected samples of human stool and vomitus that were positive by dark-field microscopy for abundant vibrios and used a microarray to compare gene expression in organisms recovered directly from the early and late stages of human infection. Our results reveal that V. cholerae gene expression within the human host environment differs from patterns defined in in vitro models of pathogenesis. tcpA, the major subunit of the essential V. cholerae colonization factor, was significantly more highly expressed in early compared with late infection; however, the genes encoding cholera toxin were not highly expressed in either phase of human infection. Furthermore, expression of the virulence regulators, toxRS and tcpPH, was uncoupled. Interestingly, the pattern of gene expression indicates that the human upper intestine may be a uniquely suitable environment for the transfer of genetic elements that are important in the evolution of pathogenic strains of V. cholerae. These findings provide a more detailed assessment of the transcriptome of V. cholerae in the human host than previous studies of organisms in stool alone and have implications for cholera control and the design of improved vaccines. The V. cholerae microarray consists of 3,890 full-length PCR products representing the annotated open reading frames from the initial release of the V. cholerae N16961 genome. Each labeling and hybridization was performed in duplicate. Genomic DNA was used as a universal internal control for the quality of the microarray and to allow for the comparison of results across multiple experiments. Data were normalized using locally-weighted regression (Lowess) to obtain the relative abundance of each transcript as an intensity ratio with respect to that of genomic DNA. High correlation coefficients were observed between technical replicates (Pearsonâs correlation coefficient (r) > 0.80) and between results of separate clinical specimens of vomitus (r > 0.77) and of stool (r > 0.80). Hence, the results from the two clinical vomitus specimens and the five clinical stool specimens were pooled. Fold changes for the relative expression of a given gene between the two clinical specimens were calculated by dividing the normalized median intensity ratios with respect to genomic DNA.
Project description:Temperature is a crucial environmental signal that govers the occurrence of Vibrio cholerae and cholera outbreaks. To understand how temperature impacts the transcriptome of V. cholerae we performed whole-genome level transcriptional profiling using custom microarrays on cells grown at human body temperature (37 C) then shifted to temperatures V. cholerae experience in the environment (15 C and 25 C).
Project description:In this study, we show that ManR (VC1825) activates the transcription of the mannose operon in M9 medium supplemented with fructose or mannose, and when manR is impaired Vibrio cholerae cells fail to colonize the intestine and host survival is significantly prolonged in a fruit fly Drosophila melanogaster infection model. To identify other target genes of ManR, transcriptome analysis was performed in wild-type V. cholerae and manR mutant strains, , grown on M9 medium supplemented with glucose, fructose, or mannose.
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.