Abstract
AbstractBacillus cereus is a clinically significant foodborne pathogen that causes severe gastrointestinal and non-gastrointestinal disease. Cereolysin O (CLO) is a putative virulence factor of B. cereus, and its function remains to be investigated. In this study, we examined the biological activity of CLO from a deep sea B. cereus isolate. CLO was highly toxic to mammalian cells and triggered pyroptosis through NLRP3 inflammasome-mediated caspase 1 and gasdermin D activation. CLO-induced cell death involved ROS accumulation and K+ efflux, and was blocked by serum lipids. CLO bound specifically to cholesterol, and this binding was essential to CLO cytotoxicity. The structural integrity of the three tryptophan residues in the C-terminal undecapeptide was vital for CLO to interact with membrane lipids and cause membrane perforation. Taken together, these results provided new insights into the molecular mechanism of B. cereus CLO-mediated cytotoxicity.
Funder
Strategic Priority Research Program of the Chinese Academy of Sciences
the Strategic Priority Research Program of the Chinese Academy of Sciences
Publisher
Springer Science and Business Media LLC