Dual bacteriocin and extracellular vesicle-mediated inhibition of <i>Campylobacter jejuni</i> by the potential probiotic candidate <i>Ligilactobacillus salivarius</i> UO.C249

Abstract

<i>Campylobacter jejuni</i> (<i>C. jejuni</i>) is a major cause of gastroenteritis and a global public health concern. The increasing antibiotic resistance and lack of effective alternatives in livestock production pose serious challenges for controlling <i>C. jejuni</i> infections. Therefore, alternative strategies are needed to control this pathogen, especially in the poultry industry where it is prevalent and can be transmitted to humans through contaminated food products. In this study, <i>Ligilactobacillus salivarius</i> UO.C249 isolated from broiler intestinal mucosa inhibited <i>C. jejuni</i> and exhibited important probiotic features. Beyond bacteriocins, <i>Lg. salivarius</i> UO.C249 secretes antimicrobial extracellular vesicles (EVs) with a unique protein set distinct from bacteriocins that are involved in transmembrane transport and peptidoglycan degradation. Our findings suggest that beyond bacteriocins, EV production is also a distinct inhibitory signaling mechanism used by <i>Lg. salivarius</i> UO.C249 to control <i>C. jejuni</i>. These findings hold promise for the application of probiotic EVs for pathogen control.