Characterization of a bacteriocin produced by Pediococcus pentosaceus SB83 for vaginal application

Bacteriocins are ribosomally synthesized and they are mainly known to have effective antimicrobial activity against pathogenic microorganisms. They have a variety of action mechanism, including cytoplasmic membrane pore formation, cell wall interference and nuclease activity (Gillor et al. 2005). Bacteriocins can be used as antimicrobial agents for improving the safety of food products and for clinical therapeutics These proteinaceous molecules appear to be capable of displacing or suppressing the growth of other bacteria, and as such, perhaps provides an advantage to microorganisms in fermenting ecosystems, including the female genital tract (Boris and Barbés 2000). As bacteriocins do not induce vaginal irritation they are suitable for human use. Listeria monocytogenes, the responsible agent for listeriosis, is one of several microorganisms which can be transmitted from mother to fetus/neonate by vertical transmission, transplacentally or during passage through the birth canal. This infection is acquired because some women carry L. monocytogenes in the vaginal tract. Vaginal infection during pregnancy represents many risks such as stillbirth, abortion, premature delivery or neonatal infection (Donati et al. 2010). Since some lactic acid bacteria (LAB) exhibit antilisterial activity, these bacteria can be used in the prevention of neonatal listeriose. Pediococcus pentosaceus SB83 was selected because previous studies demonstrated that this strain is able to inhibit the growth of clinical isolates of L. monocytogenes (serotype 1/2a, 1/2b and 4b) by production of a bacteriocin, survives in simulated vaginal fluid at normal vaginal pH (pH of 4.2) and does not show the presence of virulence factors such as the production of gelatinase, lipase and DNase, hemolytic activity and presence of virulence genes (genes esp, agg, gelE, efaAfm, efaAfs, cylA, cylB and cylM). The aim of this study was to characterize a bacteriocin produced by P. pentosaceus SB83 for potential vaginal application.