Antibacterial efficacy of nisin, pediocin 34 and enterocin FH99 against L. monocytogenes, E. faecium and E. faecalis and bacteriocin cross resistance and antibiotic susceptibility of their bacteriocin resistant variants

Abstract

The bacteriocin susceptibility of Listeria monocytogenes MTCC 657, Enterococcus faecium DSMZ 20477, E. faecium VRE, and E. faecalis ATCC 29212 and their corresponding bacteriocin resistant variants was assessed. The single and combined effect of nisin and pediocin 34 and enterocin FH99 bacteriocins produced by Pediococcus pentosaceus 34, and E. faecium FH99, respectively, was determined. Pediocin34 proved to be more effective in inhibiting L. monocytogenes MTCC 657. A greater antibacterial effect was observed against E. faecium DSMZ 20477 and E. faecium (VRE) when the a combination of nisin, pediocin 34 and enterocin FH99 were used whereas in case of L. monocytogenes MTCC 657 a combination of pediocin 34 and enterocin FH99 was more effective in reducing the survival of pathogen. Bacteriocin cross-resistance and the antibiotic susceptibility of wild type and their corresponding resistant variants were assessed and results showed that resistance to a bacteriocin may extend to other bacteriocins within the same class and also the acquired resistance to bacteriocins can modify the antibiotic susceptibility/resistance profile of the bacterial species used in the study. According to the hydrophobicity nisin resistant variant of L. monocytogenes was more hydrophobic (p<0.001), whereas the pediocin 34 and enterocin FH99 resistant variants were less hydrophobic than the wild type strain. Nisin, pediocin 34 and enterocin FH99 resistant variants of E. faecium DSMZ 20477 and E. faecium VRE were less hydrophobic than their wild type counterparts. Nisin resistant E. faecalis ATCC 29212 was less hydrophobic than its wild type counterpart.

Optimizing microencapsulation of nisin with sodium alginate and guar gum

“…Thus the protection ceases and results in challenged microbial safety and quality (Balasubramanian et al 2011). The direct application of nisin to food systems will also result in development of bacteriocin resistance of bacteria (Kaur et al 2011). Microencapsulation is an efficient technique to minimize nisin resistance development and achieve controlled release of nisin.…”

Food Safety through Natural Antimicrobials

“…Some authors have suggested the use of bacteriocin mixtures to overcome the problem of resistance [239,240] although this method is effective only when different mechanisms of resistance are implicated [189]. Cross-resistance among bacteriocins have been observed [237,[241][242][243][244] complicating the situation. The stability of Listeria monocytogenes mutant's resistance to LAB bacteriocins (mesenterocin, curvaticin, and plantaricin) was estimated by Rekhif et al [241] who found that it was maintained for several generations even when the bacteriocins were not present.…”

“…Furthermore, the mutants resistant to one of the bacteriocins showed a cross-resistance to the two other bacteriocins, but not to nisin. Nisin-resistant variants of Listeria monocytogenes as well as resistant to pediocin produced by Pediococcus pentosaceus 34, and enterocin produced by Enterococcus faecium FH99 were developed by Kaur et al [242,243]. Cross-resistance between pediocin 34 and enterocin FH 99 was found, but not with nisin.…”

Synergistically-acting Enterocin LD3 and Plantaricin LD4 Against Gram-Positive and Gram-Negative Pathogenic Bacteria

“…enterica subsp. enterica serovar Typhimurium ATCC13311, Serratia marcescens ATCC27137 and indicator strain, Micrococcus luteus MTCC106, agar well diffusion assay (AWDA) was performed overlaying soft nutrient agar (0.8%) seeded with respective pathogenic strain (~10 6 CFU/mL) on the nutrient base agar as reported previously [27]. On such plates, the wells were cut out (6.0 mm diameter) and filled with aliquots of 100 μL of enterocin LD3 (50 μg/mL) and plantaricin LD4 (50 μg/mL) independent and in combination (25 μg/mL each, total 50 μg/mL) in the wells.…”