|Abstract or Summary
- Clostridium perfringens is the causative agent of gas gangrene and the 3rd most common cause of type A food borne disease in the United States. Critical to the pathogenicity of C. perfringens is the ability of this bacterium to produce highly resistant, metabolically dormant spores that can resume metabolic function through the process of germination. Once germinated, vegetative cells can release toxins, such as the alpha toxin, the causative agent of gas gangrene. Alternatively, in type A food poisoning strains, vegetative cells can sporulate in the human gastrointestinal tract
releasing C. perfringens enterotoxin (CPE) the causative agent of type A food poisoning.
Recent work in Bacillus subtilis has identified YcsK, a phospholipase B, as having a role in the germination of B. subtilis spores possibly by modifying and disrupting one or more spore membranes. Although there are no YcsK homologues in C. perfringens, the C. perfringens alpha toxin has phospholipase C activity that also may modify and disrupt spore membranes. Therefore, our goal was to characterize the germination phenotype of C. perfringens spores lacking Plc. The novel findings of this study are five-fold:  Plc is expressed under sporulation conditions but is not under regulation by Spo0A,  Plc is necessary for normal rates of spore germination  Plc mutant spores incubated with dodecylamine and 100mM AK are able to release DPA, during the initial stages of germination, in a congruent fashion to wild-type spores,  Plc is required for normal levels of spore viability and outgrowth for a given population of phase bright spores,  Finally, pro-SleC/SleC Western blot analysis in this study showed that Plc mutant spores have less active SleC during germination than wild-type spores. Collectively, these results suggest that Plc is an important element of C. perfringens spore germination and that it acts by aiding in cortex hydrolysis by either directly or indirectly regulating the processing of SleC through an unknown mechanism.