Mechanisms of Gentamicin Resistance in Listeria monocytogenes: A Mini Review

Listeria monocytogenes is a Gram-positive foodborne pathogen capable of causing a foodborne infection known as listeriosis. There are two main types of listeriosis: a non-invasive gastroenteritis and an invasive infection which is often associated with a high mortality and hospitalization rate among susceptible individuals. Gentamicin, used as an adjunct therapy with ampicillin, remains the treatment of choice for the life-threatening invasive listeriosis. Nevertheless, there is little data on gentamicin resistance determinants in L. monocytogenes. Several well-controlled studies have reported that mechanisms of gentamicin resistance in this organism involve active efflux and genetic determinants that affect the uptake of the antibiotic through altered membrane potential. This mini review summarises current knowledge of genetic determinants of gentamicin resistance in L. monocytogenes, with the aim of contributing information that could facilitate the discovery of new therapeutic approaches to overcome, delay or avoid developments of drug resistance in this foodborne pathogen.