Department of Food Sciences, Food Microbiology, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, University of Liege, Liege, Belgium.
Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain.
Microbiologyopen. 2024 Oct;13(5):e70001. doi: 10.1002/mbo3.70001.
Clostridioides difficile is an anaerobic, spore-forming, Gram-positive pathogenic bacterium. This study aimed to analyze the effect of two samples of healthy fecal microbiota on C. difficile gene expression and growth using an in vitro coculture model. The inner compartment was cocultured with spores of the C. difficile polymerase chain reaction (PCR)-ribotype 078, while the outer compartment contained fecal samples from donors to mimic the microbiota (FD1 and FD2). A fecal-free plate served as a control (CT). RNA-Seq and quantitative PCR confirmation were performed on the inner compartment sample. Similarities in gene expression were observed in the presence of the microbiota. After 12 h, the expression of genes associated with germination, sporulation, toxin production, and growth was downregulated in the presence of the microbiota. At 24 h, in an iron-deficient environment, C. difficile activated several genes to counteract iron deficiency. The expression of genes associated with germination and sporulation was upregulated at 24 h compared with 12 h in the presence of microbiota from donor 1 (FD1). This study confirmed previous findings that C. difficile can use ethanolamine as a primary nutrient source. To further investigate this interaction, future studies will use a simplified coculture model with an artificial bacterial consortium instead of fecal samples.
艰难梭菌是一种厌氧、产芽孢、革兰氏阳性的致病性细菌。本研究旨在使用体外共培养模型分析两份健康粪便微生物群样本对艰难梭菌基因表达和生长的影响。内部隔室与艰难梭菌聚合酶链反应（PCR）-核糖型 078 的孢子共培养，而外部隔室包含供体粪便样本以模拟微生物群（FD1 和 FD2）。无粪便平板作为对照（CT）。对内部隔室样本进行 RNA-Seq 和定量 PCR 确认。在存在微生物群的情况下观察到基因表达的相似性。12 小时后，在微生物群存在的情况下，与发芽、孢子形成、毒素产生和生长相关的基因表达下调。24 小时时，在缺铁环境中，艰难梭菌激活了几个基因来对抗缺铁。与存在 FD1 供体粪便微生物群的 12 小时相比，24 小时时与发芽和孢子形成相关的基因表达上调。本研究证实了艰难梭菌可以将乙醇胺用作主要营养源的先前发现。为了进一步研究这种相互作用，未来的研究将使用简化的共培养模型，使用人工细菌联合体代替粪便样本。
