Discovery and characterisation of circular bacteriocin plantacyclin B21AG from Lactiplantibacillus plantarum B21.

Abstract

Lactiplantibacillus plantarum B21 isolated from Vietnamese sausage (nem chua) has previously displayed broad antimicrobial activity against Gram-positive bacteria including foodborne pathogens Listeria monocytogenes and Clostridium perfringens. This study successfully identified the antimicrobial agent as plantacyclin B21AG, a 5668 Da circular bacteriocin demonstrating high thermostability, resistance to a wide range of pH, proteolytic resistance and temporal stability. We report a reverse genetics approach to identify and characterise plantacyclin B21AG from first principles. The bacteriocin was purified from culture supernatant by a three-step process consisting of concentration, n-butanol..