Host-derived O-glycans inhibit toxigenic conversion by a virulence-encoding phage in Vibrio cholerae
Ontology highlight
ABSTRACT:
ORGANISM(S): Vibrio cholerae
PROVIDER: GSE213598 | GEO | 2022/12/01
REPOSITORIES: GEO
Similar Datasets
Project description:Vibrio cholerae is a Gram negative, motile, facultative anaerobic bacterium, and the causative agent of cholera, a severe diarrhoeal disease, which untreated can rapidly lead to dehydration, hypotensive shock, and death. Cholera is a significant human disease that is estimated to affect 3-5 million people each year. The mechanism by which V. cholerae regulates virulence gene expression in vivo is unknown, but a number of studies have suggested that low molecular weight signally molecules may be important in modulating gene expression. cFP is a low molecular weight cyclic dipeptide produced by multiple Vibrio species. Evidence previously generated in our laboratory showed that cFP inhibited the production of the virulence factors cholera toxin (CT) and the toxin coregulated pilus (TCP) in O1 El Tor V. cholerae strain N16961 during growth under virulence gene inducing conditions. cFP inhibition of CT and TCP production correlated with reduced transcription of several regulators that belong to the ToxR regulon. To identify additional cFP-responsive genes we performed microarray experiments with the O1 El Tor V. cholerae strain N16961. In these experiments N16961 was grown under virulence gene inducing conditions in the presence and absence of cFP before RNA was extracted and hybridized to microarrays. The results showed that cFP positively affected the expression of the LysR-family regulatory protein LeuO. This finding suggests the possibility that LeuO may be mediating cFP-dependent regulation of gene expression in response to environmental cFP. V. cholerae N16961 was grown under AKI growth condition in the presence or absence of 1 mM cFP for 2.5 or 3 hours when total RNA was extracted, differentially labelled and hybridized to microarrays. Four independent experiments were performed.
2013-08-13 | E-GEOD-38272 | biostudies-arrayexpress
Project description:Vibrio cholerae is a Gram negative, motile, facultative anaerobic bacterium, and the causative agent of cholera, a severe diarrhoeal disease, which untreated can rapidly lead to dehydration, hypotensive shock, and death. Cholera is a significant human disease that is estimated to affect 3-5 million people each year. The mechanism by which V. cholerae regulates virulence gene expression in vivo is unknown, but a number of studies have suggested that low molecular weight signally molecules may be important in modulating gene expression. cFP is a low molecular weight cyclic dipeptide produced by multiple Vibrio species. Evidence previously generated in our laboratory showed that cFP inhibited the production of the virulence factors cholera toxin (CT) and the toxin coregulated pilus (TCP) in O1 El Tor V. cholerae strain N16961 during growth under virulence gene inducing conditions. cFP inhibition of CT and TCP production correlated with reduced transcription of several regulators that belong to the ToxR regulon. To identify additional cFP-responsive genes we performed microarray experiments with the O1 El Tor V. cholerae strain N16961. In these experiments N16961 was grown under virulence gene inducing conditions in the presence and absence of cFP before RNA was extracted and hybridized to microarrays. The results showed that cFP positively affected the expression of the LysR-family regulatory protein LeuO. This finding suggests the possibility that LeuO may be mediating cFP-dependent regulation of gene expression in response to environmental cFP.
2013-08-13 | GSE38272 | GEO
Project description:Bacteria use quorum sensing (QS) to monitor cell density and coordinate group behaviours. In Vibrio cholerae, the causative agent of cholera disease, QS is linked to virulence gene expression via the autoinducer molecules, AI-2 and CAI-1. Both autoinducers share one signal transduction pathway to control AphA production, a key transcriptional activator of virulence genes. In this study, we demonstrate that the recently identified autoinducer, DPO, also controls AphA production in V. cholerae. DPO acts through the transcriptional activator, VqmA, and the VqmR small RNA to reduce AphA levels at the post-transcriptional level. Consequently, DPO inhibits virulence gene expression in V. cholerae, including repression of the cholera toxin, a key factor required for disease in humans. VqmR-mediated repression of AphA links the AI-2/CAI-1 and DPO-dependent QS pathways of V. cholerae and global transcriptome analysis indicate that all three autoinducers are required for full QS function. Together, our data provide the first view on autoinducer interplay in V. cholerae and highlight the importance of post-transcriptional gene regulation for collective functions in this major human pathogen.
2018-06-25 | GSE115711 | GEO
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
2005-08-17 | GSE2775 | GEO
Project description:Cholera is a diarrheal disease caused by Vibrio cholerae of serogroups O1 and O139 that affects impoverished populations worldwide. The histone-like nucleoid structuring protein (H-NS) is a global regulator of environmentally-regulated gene expression that plays a fundamental role in V. cholerae adaptation to disparate ecological niches. We used RNA-seq to characterize the hns transcriptome of El Tor biotype V. cholerae. H-NS affected the expression of 18% of all predicted genes in a growth phase-dependent manner. It silenced the transcription of genes encoding virulence regulators and cytotoxic factors such as the VieSAB regulatory system, the repeat in toxin (RTX) and hemolysin. H-NS was 10 times more effective in silencing the vieSAB promoter in El Tor compared to classical biotype V. cholerae. In the El Tor biotype hns mutant, VieSAB significantly enhanced the expression of cholera toxin genes. For the RTX and hemolysin, we found that overexpression of the transcription activator HlyU diminished H-NS occupancy at the hlyA promoter but not at the rtxCA and rtxBDE promoters. H-NS had a significant impact on the cell envelope and the mutant expressed elevated rpoE encoding the extracytoplamic sigma factor E (sE), though this effect was indirect. A remarkable feature of the hns transcriptome was the down-regulation of numerous methyl-accepting chemotaxis proteins in early stationary phase that translated into diminished chemotaxis toward the amino acids glycine and serine. Our study suggests that H-NS transcriptional silencing can contribute to multiple phenotypic differences observed between V. cholerae biotypes, mainly by differentially repressing the VieSAB sensory pathway. Transcriptome profiles of wild type and M-NM-^Thns mutant cells of the V. cholerae strain C7258 grown in LB medium were generated by Next Generation Sequencing using the Illumina HiSeq2000 platform. Samples from mid-exponential phase (OD600 0.5) and early stationary phase (OD600 2.0) were analyzed in duplicate
2015-02-16 | E-GEOD-62785 | biostudies-arrayexpress
Project description:Cholera is a diarrheal disease caused by Vibrio cholerae of serogroups O1 and O139 that affects impoverished populations worldwide. The histone-like nucleoid structuring protein (H-NS) is a global regulator of environmentally-regulated gene expression that plays a fundamental role in V. cholerae adaptation to disparate ecological niches. We used RNA-seq to characterize the hns transcriptome of El Tor biotype V. cholerae. H-NS affected the expression of 18% of all predicted genes in a growth phase-dependent manner. It silenced the transcription of genes encoding virulence regulators and cytotoxic factors such as the VieSAB regulatory system, the repeat in toxin (RTX) and hemolysin. H-NS was 10 times more effective in silencing the vieSAB promoter in El Tor compared to classical biotype V. cholerae. In the El Tor biotype hns mutant, VieSAB significantly enhanced the expression of cholera toxin genes. For the RTX and hemolysin, we found that overexpression of the transcription activator HlyU diminished H-NS occupancy at the hlyA promoter but not at the rtxCA and rtxBDE promoters. H-NS had a significant impact on the cell envelope and the mutant expressed elevated rpoE encoding the extracytoplamic sigma factor E (sE), though this effect was indirect. A remarkable feature of the hns transcriptome was the down-regulation of numerous methyl-accepting chemotaxis proteins in early stationary phase that translated into diminished chemotaxis toward the amino acids glycine and serine. Our study suggests that H-NS transcriptional silencing can contribute to multiple phenotypic differences observed between V. cholerae biotypes, mainly by differentially repressing the VieSAB sensory pathway.
2015-02-16 | GSE62785 | GEO
Project description:The microbial cell surface is a critical site of microbe-host interactions that often control infection outcomes. Defining the set of host proteins present at this interface has been challenging. Here, we used a surface biotinylation approach coupled to quantitative mass spectrometry to identify and quantify both bacterial and host proteins present on the surface of diarrheal fluid-derived V. cholerae in an infant rabbit model of cholera. Our data showed that V. cholerae surfaces were coated with numerous host proteins, whose abundance were driven by the presence of cholera toxin, including the C type lectin SP-D. Mice lacking SP-D had enhanced V. cholerae intestinal colonization. Additional host proteins (AnxA1, LPO and ZAG) capable of binding V. cholerae were also found to recognize distinct taxa of the murine intestinal microbiota, suggesting that these host factors may play roles in intestinal homeostasis in addition to host defense. Proteomic analysis of microbial surfaces is valuable for identifying host interactions that regulate infection and homeostasis with both pathogens and endogenous microbiota alike.
2021-10-02 | PXD027076 | Pride
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.
2010-06-09 | E-GEOD-2775 | biostudies-arrayexpress
Project description:The microbial cell surface is a critical site of microbe-host interactions that often control infection outcomes. Defining the set of host proteins present at this interface has been challenging. Here, we used a surface biotinylation approach coupled to quantitative mass spectrometry to identify and quantify both bacterial and host proteins present on the surface of diarrheal fluid-derived V. cholerae in an infant rabbit model of cholera. Our data showed that V. cholerae surfaces were coated with numerous host proteins, whose abundance were driven by the presence of cholera toxin, including the C type lectin SP-D. Mice lacking SP-D had enhanced V. cholerae intestinal colonization. Additional host proteins (AnxA1, LPO and ZAG) capable of binding V. cholerae were also found to recognize distinct taxa of the murine intestinal microbiota, suggesting that these host factors may play roles in intestinal homeostasis in addition to host defense. Proteomic analysis of microbial surfaces is valuable for identifying host interactions that regulate infection and homeostasis with both pathogens and endogenous microbiota alike.
2021-07-08 | GSE179529 | GEO
Project description:The microbial cell surface is a critical site of microbe-host interactions that often control infection outcomes. Defining the set of host proteins present at this interface has been challenging. Here, we used a surface biotinylation approach coupled to quantitative mass spectrometry to identify and quantify both bacterial and host proteins present on the surface of diarrheal fluid-derived V. cholerae in an infant rabbit model of cholera. Our data showed that V. cholerae surfaces were coated with numerous host proteins, whose abundance were driven by the presence of cholera toxin, including the C type lectin SP-D. Mice lacking SP-D had enhanced V. cholerae intestinal colonization. Additional host proteins (AnxA1, LPO and ZAG) capable of binding V. cholerae were also found to recognize distinct taxa of the murine intestinal microbiota, suggesting that these host factors may play roles in intestinal homeostasis in addition to host defense. Proteomic analysis of microbial surfaces is valuable for identifying host interactions that regulate infection and homeostasis with both pathogens and endogenous microbiota alike.
2021-07-08 | GSE179528 | GEO