Project description:Gene expression level of Clostridioides difficile (C. difficile) strain R20291 comparing control C. difficile carring pMTL84151 as vector plasmid with C. difficile conjugated with a pMTL84151-03890 gene. Goal was to determine the effects of 03890 gene conjugation on C. difficile strain R20291 gene expression.
Project description:The intestines house a diverse microbiota that must compete for nutrients to survive, but the specific limiting nutrients that control pathogen colonization are not clearly defined. Clostridioides difficile colonization typically requires prior disruption of the microbiota, suggesting that outcompeting commensals for resources is key in establishing C. difficile infection (CDI). The immune protein calprotectin (CP) is released into the gut lumen during CDI to chelate zinc (Zn) and other essential nutrient metals. Yet, the impact of Zn limitation on C. difficile colonization is unknown. To define C. difficile responses to Zn limitation, we performed RNA sequencing on C. difficile exposed to CP. In media with CP, C. difficile upregulated genes involved in metal homeostasis and amino acid metabolism.
Project description:Clostridioides difficile interactions with the gut mucosa are crucial for colonisation and establishment of infection, however key infection events during the establishment of disease are still poorly defined. To better understand the initial events that occur during C. difficile colonisation, we employed a dual RNA-sequencing approach to study the host and bacterial transcriptomic profiles during C. difficile infection in a dual-environment in vitro human gut model. Temporal changes in gene expression were analysed over 3-24h post infection and comparisons were made with uninfected controls.
Project description:Clostridioides difficile is one of the most common nosocomial pathogens and a global public health threat. Upon colonization of the gastrointestinal tract, C. difficile is exposed to a rapidly changing polymicrobial environment and a dynamic metabolic milieu. Despite the link between the gut microbiota and susceptibility to C. difficile, the impact of synergistic interactions between the microbiota and pathogens on the outcome of infection is largely unknown. Here, we show that microbial cooperation between C. difficile and Enterococcus has a profound impact on the growth, metabolism, and pathogenesis of C. difficile.. Through a process of nutrient restriction and metabolite cross-feeding, E. faecalis shapes the metabolic environment in the gut to enhance C. difficile fitness and increase toxin production. These findings demonstrate that members of the microbiota, such as Enterococcus, have a previously unappreciated impact on C. difficile behavior and virulence.
Project description:We illustrate how metabolically distinct species of Clostridia can protect against or worsen Clostridioides difficile infection, modulating the pathogen's colonization, growth, and virulence to impact host survival. Gnotobiotic mice colonized with the amino acid fermenter Paraclostridium bifermentans survived infection while mice colonized with the butyrate-producer, Clostridium sardiniense, more rapidly succumbed. Systematic in vivo analyses revealed how each commensal altered the gut nutrient environment, modulating the pathogen's metabolism, regulatory networks, and toxin production. Oral administration of P. bifermentans rescued conventional mice from lethal C. difficile infection via mechanisms identified in specifically colonized mice. Our findings lay the foundation for mechanistically informed therapies to counter C. difficile disease using systems biologic approaches to define host-commensal-pathogen interactions in vivo.
Project description:Clostridioides difficile can cause severe infections in the gastrointestinal tract and affects almost half a million people in the U.S every year. Upon establishment of infection, a strong immune response is induced. We sought to investigate the dynamics of the mucosal host response during C. difficile infection.
Project description:The Clostridioides difficile toxins TcdA and TcdB are responsible for diarrhea and colitis. The aim of this project was to explore the effects of the toxins on epithelial barrier function and the molecular mechanisms for diarrhea and inflammation. RNA-seq of toxin-treated intestinal cell monolayers was performed to describe the C. difficile-mediated effects. mRNA profiles from intestinale epithelial cells were generated by deep sequencing using Illumina NovaSeq 6000. This data provide the basis for subsequent upstream regulator analysis.
Project description:The experiment intends to reveal the difference in gene expression profiles between the wild-type strain and the ∆cwp66 mutant of Clostridioides difficile. We first constructed the ∆cwp66 mutant, and the phenotypic changes of the ∆cwp66 mutant against the wild-type strain were studied. To further elucidate the mechanism of phenotypic changes of the ∆cwp66 mutant, RNA-sequencing experiments were carried out to reveal the underlying mechanism of phenotypic changes.
Project description:Metabolomic and transcriptomic analysis of changes in the exponential and stationary phase of Clostridioides difficile after cultivation in casamino acids medium (reference) and supplemented with L-lactate and the connection to toxin production.
Project description:We compared transcriptomes of wild-type and ∆vanS strains of Clostridioides difficile 630 growing in the presence or absence of peptidoglycan-targeting antibiotics, vancomycin or ramoplanin. VanS is a histidine kinase of a two-component system that regulates expression of the vancomycin-induced vanG operon.
