We further evaluated the export and lipidation of OspA and its mutant by Triton X-114 phase partitioning of the cell envelope ( Fig. 2 ). In the cell envelope of Lactobacillus, OspA partitions to the detergent phase, suggesting that OspA is exported through the membrane and that the amount of OspA that is hydrophobic (,50%) is higher than the hydrophilic form (,40%), although not significantly so. In contrast, the mutant OspA D17 partitions mostly to the aqueous phase, suggesting that, in addition to being exported, the mutant generated more hydrophilic OspA (,70%) than hydrophobic (,25%) ( Fig. 2A and 2B ). If about 25% of OspA is associated with the cell envelope due to hydrophobicity of the leader sequence (i. e. OspA D17 in the detergent phase of LpA D17 ), then the difference (i. e. ,30% additional wildtype OspA in the detergent phase of LpA) should be protein that is associated with the cell envelope via the lipid anchor, or the lipidated form of OspA. Differences for the mutant OspA D17 partitions are statistically significant (Fig. 2B , *p,0.05).