Document Type : Research Paper

Authors

Abstract

Hemolysin is an extracellular protein released by many pathogenic and nonpathogenic bacteria. It belongs to cholesterol-dependent cytolysins (CDCs) which are a large family of pore-forming toxins. Their mechanism of action is cholesterol identification as a receptor. In this study, a type of hemolysin produced by Bacillus pumilus SAFR0032 was investigated. Firstly, molecular dynamic simulations of Hemolysin in biological membranes were performed using Gromax software to evaluate the stability of proteins in biological membranes. Amino acids which involved in toxin-membrane interactions were also identified by Autodock software. Subsequently, crucial mutations were created in the key amino acids of interaction and function of mutant proteins were checked by Pop Music server. Our findings demonstrated that critical hemolysin mutations could reduce hemolysin tendency to cholesterol and weaken their interaction. All in all suggesting that three-dimensional structure of hemolysin can be considered as a novel concept in pharmaceutical field to improve current drugs which used to cure hemolysin-associated diseases.

Keywords

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