Previously, we reported the cloning and expression of full length OspA from B. burgdorferi in a lactobacilli expression vector and designed an oral vaccine candidate for Lyme disease (LpA) [12] . For this study, we mutated the conserved lipidation motif of ospA by replacing the cystein at position 17 with aspartic acid to generate a protein that lacks the post-translational lipid attachment (Fig.1A) . Total extracts of L. plantarum carrying the empty vector (Lp), and expressing OspA (LpA) or OspA D17 (LpA D17 ) were analyzed by SDS-PAGE and protein expression was confirmed using anti-OspA monoclonal antibody, mAb 184.1 (Fig.1B) . The two bands seen for LpA may represent the lipidated unprocessed OspA protein (the leader peptide has not been cleaved, 31 kDa) and the lipidated mature protein (the leader peptide has been cleaved, 30 kDa). The single band seen for LpA D17 (30.4 kDa) may represent the unlipidated OspA (containing the leader peptide).