CENTRO DE REFERENCIA PARA LACTOBACILOS
Unidad Ejecutora - UE
Combinations of subclass IIa bacteriocins with antimicrobials that act at membrane and cell wall level
EMILIANO SALVUCCI; FERNANDO SESMA
LETTERS IN APPLIED MICROBIOLOGY
Objective: Subclass IIa bacteriocins are peptides ribosomally synthesized with antilisterial activity. Enterocin CRL35, subclass IIa bacteriocin produced by Enterococcus mundtii CRL35 was evaluated in combination with monensin, bacitracin, gramicidin and mutanolysin. Materials and methods: In vitro activities of different antibiotic were evaluated. MICs and FICs assays were performed by growth inhibition in microplates using Listeria (L.) innocua as sensitive cell. Fluorescence assays to evaluate dissipation of membrane potentials in intact cells were carried out.Results: The antimicrobials evaluated showed an additive effect with enterocin CRL35. Monensin displayed the strongest activity (CIM: 0,5 ìg/mL). Listeria innocua showed high tolerance to mutanolysin (500 AU/mL) and it could protect sensitive cells from the action of high concentrations of bacteriocin.