FIG. 6.

The locations of heme motifs, cysteine-to-serine substitutions, and the predicted alpha helix membrane-anchoring domain (underlined) in CymA (A) and growth on arsenate of four cymA heme mutants containing single cysteine-to-serine substitutions (B). The time course for growth was inferred from the optical density at 600 nm. •, CN-32 plus vector; ▪, CN-CYMA plus vector; ⧫, pH 1(C46S); ×, pH 2(C78S); +, pH 3(C136S); ▴, pH 4(C173S). The data points and error bars represent the means and standard deviations of triplicate cultures, respectively.