SDS-PAGE analysis and immunoblotting analysis. SDS-PAGE analysis (A) and Western blot analysis (B) of recombinant E. coli XL10-Gold cells expressing OmpW-PerPA fusion proteins were performed. Lane 1, whole-cell lysate of XL10-Gold harboring pOW19F-PerPA1; lane 2, outer membrane fraction of XL10-Gold harboring pOW19F-PerPA1; lane 3, whole-cell lysate of XL10-Gold harboring pOW19F-PerPA2; lane 4, outer membrane fraction of XL10-Gold harboring pOW19F-PerPA2; lane 5, whole-cell lysate of XL10-Gold harboring pOW19F-PerPA3; lane 6, outer membrane fraction of XL10-Gold harboring pOW19F-PerPA3; lane 7, whole-cell lysate of XL10-Gold harboring pOW19F-PerPA4; lane 8, outer membrane fraction of XL10-Gold harboring pOW19F-PerPA4; lane M, molecular mass standards.