Heterologous production of pediocin PA-1 in Lactobacillus reuteri

Abstract

The recombinant DNA pLR5cat_PSAB in which pediocin PA-1 structural and immunity genes (pedAB) fused with the promoter and deduced signal sequence of an alpha-amylase gene from a bifidobacterial strain were inserted in pLR5cat, an Escherichia coli-lactobacilli shuttle vector was transferred to Lactobacillus reuteri KCTC 3679 and the transformant presented bacteriocin activity. The recombinant L. reuteri KCTC 3679 transformed with the shortened pLR5cat(S)_PSAB, where non-essential region for the lactobacilli replicon was removed, also showed bacteriocin activity. The molecular mass of the secreted pediocin PA-1 from the recombinant bacteria was the same as that of native pediocin PA-1 (~4.6 kDa) from Pediococcus acidilactici K10 on a sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) gel. In co-cultures with Listeria monocytogenes, the recombinant L. reuteri KCTC 3679 effectively reduced the viable cell count of the pathogenic bacterium by a 3 log scale compared with a control where L. monocytogenes was incubated alone.