Localization and stability of FlgS proteins in C. jejuni. Wild-type strain C. jejuni 81-176 Smr (DRH212) (WT), 81-176 Smr ΔflgS (DRH460), and 81-176 Smr flgS(H141A) (DRH1323) were grown, and protein samples were obtained from the WCL, the soluble fraction (Sol), and the insoluble membrane fraction (Mem) after sonication. Anti-FlgS Rab11 antiserum (α-FlgS) was used to detect FlgS proteins (25). Anti-RpoA M59 antiserum (α-RpoA) and anti-AtpF M3 antiserum (α-AtpF) were used to detect the soluble cytoplasmic RpoA protein and the insoluble inner membrane protein AtpF, respectively (4).