Detection of mobile genetic elements in pediocin PA-1 like producing lactic acid bacteria

To evaluate the presence of mobile genetic elements (MGEs) in intergeneric and interspecific pediocin producing lactic acid bacteria (LAB) the flanking regions of the pediocin PA-1/AcH (pediocin PA-1) operon was characterized. In Enterococcus faecium Acr4 and Lactobacillus plantarum Acr2 a variation in the amplicon size in the downstream region of the operon was identified, suggesting a deletion in this region. Beyond that, in pediocin PA-1 encoding plasmids MGEs such as ISLpl1 and mobilization regions were detected by Southern hybridization analysis. Phylogenetic analyses of the E. faecium Acr4 ISLpl1 gene sequence suggested the gene transfer from lactobacilli in the environment. The tyrosine recombinase detected in pediocin plasmids of Pediococcus acidilactici H and K7 indicate a possible transfer of the entire operon among LAB. Since these elements are known to be associated with transfer of genes linked to the bacteriocin production, antibiotic resistance, and sugar utilization, we suggest similar mechanism for natural spread of pediocin PA-1 operon among different bacterial species.