Advances in efflux pump-mediated multidrug resistance of Listeria monocytogenes

Abstract:

Listeria monocytogenes, a major zoonotic food-borne intracellular pathogen, is ubiquitous in the natural environment and easily contaminates animal-derived food products. The consumption of the contaminated food can cause severe listeriosis in both humans and animals, with the mortality rate reaching up to 30%. The antimicrobial therapy is the only feasible approach for treating L. monocytogenes infection since L. monocytogenes is susceptible to multiple antimicrobials. However, the reports of multidrug-resistant strains are increasing due to the selective pressure exerted by the irrational use of antimicrobials or disinfectants. The antimicrobial resistance mechanisms of L. monocytogenes are complex. Efflux pump proteins are crucial in bacteria and participate in various biological processes. Specifically, they can influence bacterial sensitivity to antibiotics, facilitate the efflux of toxic compounds, and affect bacterial virulence. Over the last two decades, scholars have conducted research on the efflux pumps-mediated resistance of L. monocytogenes, identifying several efflux pump proteins associated with the efflux of antibiotics or toxic compounds. Additionally, some efflux pumps are involved in the virulence expression process of L. monocytogenes. This paper reviews the research advances in the functions and regulatory mechanisms of efflux pumps in multidrug-resistant L. monocytogenes. It provides a theoretical foundation for probing into the environmental adaption mechanisms of L. monocytogenes, curbing the spread of this pathogen, and identifying new drug targets for combating infections.