Sensitivity of nisin-resistant Listeria monocytogenes to heat and the synergistic action of heat and nisin

Abstract

K . D . M O D I , M . L . C H I K I N D A S A N D T . J . M O N T V I L L E . 2000.Nisin, a bacteriocin produced by some strains of Lactococcus lactis, acts against foodborne pathogen Listeria monocytogenes. A single exposure of cells to nisin can generate nisin-resistant (Nis r ) mutants, which may compromise the use of nisin in the food industry.The objective of this research was to compare the heat resistance of Nis r and wild type (WT) Listeria monocytogenes.The synergistic e¡ect of heat-treatment (55 C) and nisin (500 IU ml À1 ) on the Nis r cells and the WT L. monocytogenes Scott Awas also studied. When the cells were grown in the absence of nisin, there was no signi¢cant (a 0Í05) di¡erence in heat resistance betweenWTand Nis r cells of L. monocytogenes at 55, 60 and 65 C. However, when the Nis r cells were grown in the presence of nisin, they were more sensitive to heat at 55 C than the WT cells.The D-values at 55 C were 2Í88 and 2Í77 min for Nis r ATCC 700301and ATCC 700302, respectively, which was signi¢cantly (a 0Í05) lower than the D-value for WT, 3Í72 min.When Nis r cells were subjected to a combined treatment of heat and nisin, there was approximately a four log reduction during the ¢rst 7 min of treatment.

Bacteriocin-Antimicrobial Synergy: A Medical and Food Perspective

“…While bacteriocins interacting synergistically with other antimicrobials and stressors could have great potential in clinical and food settings, one must be aware that unfortunately, bacteriocins are by no means a “magic bullet” and are not exempt from development of resistance (Modi et al, 2000; Draper et al, 2015). Indeed, several different mechanisms of resistance to the lantibiotic subclass of bacteriocins have been described, which include cell-envelope altering mechanisms utilized by bacteria such as DltA or MprF (Peschel et al, 1999; Poyart et al, 2001; Abachin et al, 2002; Kovacs et al, 2006; Khattar et al, 2009; McBride and Sonenshein, 2011a,b), two component systems such as CprK in C. difficile (McBride and Sonenshein, 2011a,b; Suarez et al, 2013) and LisRK in L. monocytogenes (Cotter et al, 1999; Kallipolitis and Ingmer, 2001), as well as other mechanisms such as production of nisin resistance proteins (Chatterjee et al, 2005; O'Driscoll et al, 2006; Khosa et al, 2013) (for a comprehensive review on lantibiotic resistance, see Draper et al, 2015).…”

The Acid Tolerance Response Alters Membrane Fluidity and Induces Nisin Resistance in Listeria monocytogenes

“…Nisin is active against many foodborne pathogens including L. monocytogenes, Staphylococcus aureus, Bacillus cereus and Clostridium botulinum [2,13,37]. It has synergistic effects with antimicrobials such as polylysine, thymol and others [1,3,16,31,33,37]. It is approved by the FDA as generally recognized as safe (GRAS) for use as preservative in a variety of food products [18].…”

Nisin‐resistant (Nisr) Listeria monocytogenes and Nisr Clostridium botulinum Are Not Resistant to Common Food Preservatives

“…Changes in the membrane composition of nisin-resistant strains that interfere with the action of one bacteriocin affect the antimicrobial activity of other bacteriocins that act at the cytoplasmic membrane. Resistance to nisin-conferred cross-resistance to other antimicrobial peptides but did not confer intrinsic resistance to heat (Mazzotta and Montville 1999;Modi 1999) or the other preservative tested in this study, which act on the cell by different mechanisms.…”