Clostridioides difficile Biology: Sporulation, Germination, and Corresponding Therapies for C. difficile Infection

<i>Clostridioides difficile</i> is a Gram-positive, spore-forming, toxin-producing anaerobe, and an important nosocomial pathogen. Due to the strictly anaerobic nature of the vegetative form, spores are the main morphotype of infection and transmission of the disease. Spore formation and their subsequent germination play critical roles in <i>C. difficile</i> infection (CDI) progress. Under suitable conditions, <i>C. difficile</i> spores will germinate and outgrow to produce the pathogenic vegetative form. During CDI, <i>C. difficile</i> produces toxins (TcdA and TcdB) that are required to initiate the disease. Meanwhile, it also produces spores that are responsible for the persistence and recurrence of <i>C. difficile</i> in patients. Recent studies have shed light on the regulatory mechanisms of <i>C. difficile</i> sporulation and germination. This review is to summarize recent advances on the regulation of sporulation/germination in <i>C. difficile</i> and the corresponding therapeutic strategies that are aimed at these important processes.