Fig. 7. The pacC^+/–209(L498S) mutation prevents both formation of the intermediate and processing. (A) Western analysis of PacC in extracts from pacC⁺ cells grown under acidic conditions (H⁺) and shifted to alkaline conditions, using α-PacC(5–265) antiserum. Samples were taken at the different time points indicated after the pH shift. FL, translation product; IT, intermediate; P, processed. (B) A similar experiment using mutant pacC^+/–209 cells. (C) A similar experiment using mutant pacC^c69 cells. In acidic growth conditions, the pacC^c69(L340S) product is converted to the processed form without passing through the intermediate. An extract of an alkaline-grown wild-type is a control.