Project description:Amidochelocardin is an atypical tetracycline which was previously shown to target the bacterial cell membrane although its detailed mode-of-action is still unknown. To gain insight into Clostridioides difficile’s response to membrane targeting antibiotics and to further study the mode-of-action of Amidochelocardin, the stress response of C. difficile 630 to sublethal doses of amidochelocardin were studied on the proteome level. The results and results from downstream experiments, such as quantification of the membrane potential, cellular localization assays and transmission electron microscopy analysis, suggest that amidochelocardin kills bacteria such as C. difficile by dissipating their membrane potential. Furthermore, the data suggest that C. difficile responds to dissipation of the membrane potential by induction of biosynthesis of an hitherto unknown aromatic compound.
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: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:Systems biology approach of Clostridioides difficile to analyze the temporal changes in the intracellular and extracellular metabolme, transcriptome and proteome along the growth curve in casamino acids medium and the connection to toxin production.
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 gut microbiome engenders colonization resistance against the diarrheal pathogen Clostridioides difficile but the molecular basis of this colonization resistance is incompletely understood. A prominent class of gut microbiome-produced metabolites important for colonization resistance against C. difficile is short chain fatty acids (SCFAs). In particular, one SCFA (butyrate) decreases the fitness of C. difficile in vitro and is correlated with C. difficile-inhospitable gut environments, both in mice and in humans. Here, we demonstrate that butyrate-dependent growth inhibition in C. difficile occurs under conditions where C. difficile also produces butyrate as a metabolic end product. Furthermore, we show that exogenous butyrate is internalized into C. difficile cells and is incorporated into intracellular CoA pools where it is metabolized in a reverse (energetically unfavorable) direction to crotonyl-CoA and (S)-3-hydroxybutyryl-CoA and/or 4-hydroxybutyryl-CoA. This internalization of butyrate and reverse metabolic flow of butyrogenic pathway(s) in C. difficile coincides with alterations in toxin release and sporulation. Together, this work highlights butyrate as a marker of a C. difficile inhospitable environment to which C. difficile responds by releasing its diarrheagenic toxins and producing environmentally-resistant spores necessary for transmission between hosts. These findings provide foundational data for understanding the molecular and genetic basis of how C. difficile growth is inhibited by butyrate and how butyrate alters C. difficile virulence in the face of a highly competitive and dynamic gut environment.
2023-12-21 | GSE249810 | GEO
Project description:transmission chain of oxazolidinone resistance genes through one health approach
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:Detection of clostridithiols from heterologous expression of one or both putative genes for clostridithiol biosynthesis (originating from Clostridioides difficile wild-type 630) in liquid cultures of E. coli BL21(DE3) grown in modified minimal medium
Project description:Clostridioides difficile is the major pathogen causing diarrhea following antibiotic treatment. It is considered to be a strictly anaerobic bacterium, however, previous studies have shown a certain and strain-dependent oxygen tolerance. In this study, the model strain C. difficile 630Δerm was shifted to micro-aerobiosis and was found to stay growing to the same extent as anaerobically growing cells for the duration tested. However, an extensive change in gene expression was determined by RNA-Seq with 49 effected genes after 15 min and more than 400 after one hour. Effected genes exhibit a wide range of functionality, including the metabolism of amino acids, enzymes for cell wall synthesis, the uptake and metabolism of sugars, synthesis of B vitamins as well as purine synthesis and DNA repair. Our study suggests that tolerance of C. difficile towards O2 is based on a complex and far-reaching adjustment of global gene expression.