Figure 2.

Spa33^CC arises from an alternative start codon and is required for protein secretion. (a) Whole cell extracts (WCE) of the E. coli strains (TOP10) harboring plasmid expressing Spa33‐His or its mutated derivative (Spa33^M237A) were analyzed by immunoblotting with anti‐His antibodies. (b) Coomassie blue staining (upper panel) or Western blot (lower panels) analysis of secreted proteins by the wild‐type strain (WT), the spa33 mutant (∆spa33), the spa33 mutant complemented with pSU18‐spa33 (pSpa33) or its mutated derivative (pSpa33^M237A), with or without Spa33^C‐CC (+ or − pSpa33^C), under CR induction (CR sup.) and using IpaC, IpaB, IpaD, MxiC, IpaA, and IscB antibodies. Mw: molecular weight in kDa