The Lipoteichoic Acid-Related Proteins YqgS and LafA Contribute to the Resistance of Listeria monocytogenes to Nisin
Xinxin Pang, Yansha Wu, Xiayu Liu, Yajing Wu, Qin Shu, Jianrui Niu, Qihe Chen, Xinglin Zhang
Abstract
Listeria monocytogenes is an opportunistic Gram-positive pathogen responsible for listeriosis, and is widely present in a variety of foods including ready-to-eat foods, meat, and dairy products. Nisin is the only licensed lantibiotic by the FDA for use as a food-grade inhibitor in over 50 countries. A prior study suggests that L. monocytogenes are more resistant than other Gram-positive pathogens in nisin-mediated bactericidal effects. However, the mechanisms of L. monocytogenes involved in nisin resistance have not yet to be fully defined. Here, we used a mariner transposon library to identify nisin-resistance-related genes on a genome-wide scale via transposon sequencing. We found, for the first time, that YqgS and LafA (Lipoteichoic acid-related proteins) are required for resistance to nisin. Subsequently, we investigated the roles of YqgS and LafA in L. monocytogenes stress resistance, antimicrobial resistance, biofilm formation, and virulence in mammalian cells.