Bacteriocins of Pediococcus

Abstract

Etchells et al. (1964) found that Pediococcus pentosaceus FBB-61 delayed the onset of growth of Lactobacillus plantarum FBB-67 in fermenting cucumbers. Also Haines & Harmon (1973) and Daly et al. (1973) reported on the inhibition of Staphylococcus aureus by pediococcal starter cultures. Fleming et al. (1975), who compared the inhibitory properties of 16 pediococcal cultures from various sources against a variety of microorganisms, finally clearly showed the antagonistic capacity of two Pediococcus spp., namely P. pentosaceus FBB-61 and P. pentosaceus L-7230. These strains were isolated from fermenting cucumber brines and were inhibitory towards P. pentosaceus, P. acidilactici, Lb. plantarum, Leuconostoc mesenteroides subsp. mesenteroides, Micrococcus luteus, Enterococcus faecalis, Staphylococcus aureus, Bacillus cereus and Clostridium spp. Later, Hoover et al. (1989) found that P. pentosaceus FBB-61 was also effective against Listeria monocytogenes. Neither of the two inhibitory Pediococcus strains was active against Gram-negative bacteria, yeasts, or each other. Fleming et al. (1975) ruled out the possibility that the inhibitory agent was hydrogen peroxide by using catalase in their assays. Rueckert (1979) finally characterized the chemical nature of the inhibitory agent produced by P. pentosaceus FBB-61. He found that it was bactericidal, non-dialyzable, stable to heat (100°C for 60 min) and freezing, and sensitive to pronase, and concluded that the inhibitor was bacteriocin-like. Daeschel & Klaenhammer (1985) called it pediocin A and linked inhibitor production and host cell immunity with a plasmid of 13.6 MDa (pMD136). Graham & McKay (1985) found only one of the Pediococcus spp. screened during their study to produce bacteriocin, namely P. pentosaceus FBB-63. The strain was inhibitory to other species of pediococci, which confirmed the findings of Fleming et al. (1975). This bacteriocin-like substance was tentatively linked to a 10.5 MDa plasmid after being cured with novobiocin (Graham & McKay, 1985).