Clostridioides difficile strains were isolated from manure and digestate samples from five biogas plants in France. The objective of this study was to characterize these isolates using PCR ribotyping, wgMLST, a multiplex PCR targeting genes encoding for the main virulence factors, i.e. tcdA, tcdB, cdtA and cdtB, and antimicrobial susceptibility assays. The 54 strains characterized were all positive for tcdA and tcdB and 83% (45/54) were positive for the binary toxin genes. PCR ribotypes 126 (59%) and 078 (37%) were predominant, and wgMLST analysis of 18 isolates showed close proximity of strains within a single biogas plant. Samples from the biogas plant supplied with cattle and poultry manure displayed the largest variety in PCR ribotypes. The in vitro activities of nine antimicrobial agents were determined. All the strains were susceptible to vancomycin and metronidazole, which are currently considered first-line treatments for C. difficile infection in humans. All the strains were resistant to clindamycin. The results of this study show that a high percentage of C. difficile strains present in the French biogas plants investigated are toxigenic strains from PCR ribotypes also commonly found in humans.

从法国五个沼气厂的粪便和消化样品中分离出艰难梭菌菌株。这项研究的目的是使用PCR核糖分型法，wgMLST，编码主要毒力因子（即tcdA，tcdB，cdtA和cdtB）的多重PCR的多重PCR以及抗菌药敏试验来表征这些分离株。表征的54个菌株均对tcdA和tcdB呈阳性二元毒素基因阳性率为83％（45/54）。PCR核型为126（59％）和078（37％），并且对18个分离株的wgMLST分析表明，菌株在单个沼气厂内非常接近。来自提供牛和家禽粪便的沼气厂的样品显示出PCR核型最大的多样性。在体外九种抗菌药物活性进行了测定。所有菌株均对万古霉素和甲硝唑敏感，目前被认为是人类艰难梭菌感染的一线治疗方法。所有菌株均对克林霉素具有抗性。这项研究的结果表明，艰难梭菌的百分比很高 在法国所研究的沼气厂中存在的毒株是来自PCR核型的产毒株，也常在人类中发现。