Evidence suggests that the peptidoglycan layer of some LAB promote natural immuno-adjuvanticity [13] , [14] , [15] , [16] and antigen localization on the cell wall makes it more accessible to the immune system as compared to intracellular or secreted proteins [17] , [18] . Leader peptides mark proteins for translocation across the cytoplasmic membrane and lipid modification is of major importance both for anchoring exported proteins to the membrane and for protein function [19] . It has been shown that lipidation at the first aminoacid of the mature OspA protein is essential to induce an immune response [20] , [21] . In this study, we examined the influence of post-translational processing in the localization of OspA lipoprotein on the cell envelope of L. plantarum.