Project description:Clostridioides difficile infection (CDI), characterized by colitis and diarrhea, afflicts approximately half a million people in the United States every year, burdening both individuals and the healthcare system. C. difficile 630Δerm is an erythromycin-sensitive variant of the clinical isolate C. difficile 630 and is commonly used in the C. difficile research community due to its genetic tractability. 630Δerm possesses a point mutation in perR, an autoregulated transcriptional repressor that regulates oxidative stress resistance genes. This point mutation results in a constitutively de-repressed PerR operon in 630Δerm. To address the impacts of perR on phenotypes relevant for oxygen tolerance and relevant to a murine model of CDI, we corrected the point mutant to restore PerR function in 630∆erm (herein, 630∆erm perRWT). We demonstrate that there is no difference in growth between 630Δerm and a 630Δerm perRWT under anaerobic conditions or when exposed to concentrations of O2 that mimic those found near the surface of the colonic epithelium. However, 630∆erm perRWT is more sensitive to ambient oxygen than 630∆erm, which coincides with alterations in expression of a variety of perR-dependent and perR-independent genes. Finally, we show that 630∆erm and 630∆erm perRWT do not differ in their ability to infect and cause disease in a well-established murine model of CDI. Together, these data support the hypothesis that the perR mutation in 630∆erm arose as a result of exposure to ambient oxygen and that the perR mutation in 630∆erm is unlikely to impact CDI-relevant phenotypes in laboratory studies
Project description:Investigation of whole genome gene expression level changes in a Clostridium difficile fur (ferric uptake regulator) mutant, compared to the wild type strain 630 erm. The fur mutant analyzed in this study is further described in Ho and Ellermeier (2015) J. Bacteriology A microarray study using total RNA recovered from three separate wild type cultures of Clostridium difficile 630 erm strain and three separate cultures of a fur mutant strain (ltrA::ermR) were grown in Tryptone-Yeast Extract medium containing 0.25 mM ferric chloride . Each chip measures the expression level of 3,786 of the 3,787 open reading frames of the C. difficile 630 genome with 18 probes (60 oligomers each) for each gene.
Project description:Investigation of whole genome gene expression level changes in a Clostridium difficile fur (ferric uptake regulator) mutant, compared to the wild type strain 630 erm. The fur mutant analyzed in this study is further described in Ho and Ellermeier (2015) J. Bacteriology
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.
Project description:Clostridioides difficile is the leading cause of antibiotics-associated diarrhea but can also result in more serious, life-threatening conditions. As incidence of C. difficile infections in hospitals is increasing, both in frequency and severity, and antibiotic-resistant C. difficile strains are advancing, antimicrobial peptides (AMPs) are an interesting alternative to classic antibiotics. Knowledge on the effects of AMPs on C. difficile will therefore not only enhance the knowledge for possible biomedical application but may also provide insights in mechanisms of C. difficile to adapt or counteract AMPs. This study applies state-of-the-art mass spectrometry methods to quantitatively investigate the proteomic response of C. difficile 630∆erm to sublethal concentrations of the AMP nisin allowing to follow the cellular stress adaptation in a time-resolved manner. The results do not only point at a heavy reorganization of the cellular envelop but also determined pronounced changes in central cellular processes such as carbohydrate metabolism. Moreover, the number of flagella per cell was changed during the process of adaptation to nisin suggesting a role of these cellular structures in combating this particular AMP, which is independent from pure cell motility
2021-02-18 | PXD021684 | Pride
Project description:Transcriptome sequencing from Clostridium difficile 630 Delta erm in iron replete conditions
