Antibacterial protein helveticin NX371 fused with penetrating peptide response to Vibrio parahaemolyticus in salmon

Abstract Vibrio parahaemolyticus is a prevalent foodborne pathogen associated with seafood and is a significant causative agent of foodborne illness. There is a market demand for enhancing food safety and quality through the use of bacteriocins derived from lactic acid bacteria to control V. parahaemolyticus infections. This study focuses on enhancing the efficacy of the bacteriocin Helveticin NX371, derived from Lactobacillus helveticus, against V. parahaemolyticus. This was achieved by modifying the surface charge and employing the fusion and expression of transmembrane peptides. Among the tested combinations, NX371 + OP4 significantly reduced the minimum inhibitory concentration (MIC) against V. parahaemolyticus from 180 µg/mL to 35 µg/mL, representing a decrease of 80.5%. In salmon artificially contaminated with V. parahaemolyticus, NX371 + OP4 demonstrated a potent bactericidal effect, achieving a mortality rate of 93.3%. Furthermore, throughout a 12-day storage period, the concentration of V. parahaemolyticus remained below 10^5 CFU/g. This study offers an effective strategy for preventing V. parahaemolyticus contamination in seafood and enhancing its shelf life.