FIG 8.

Abundance of protein A and alpha toxin in xerC mutants. (A) The relative abundance of protein A (Spa), as assessed by measuring the amount of extracellular Spa (eSpa) in clarified supernatants, was assessed in LAC, UAMS-1, and the indicated mutants by Western blotting. (B) The relative amounts of alpha toxin in LAC and the indicated mutants were assessed by Western blotting. An alpha toxin mutant (hla) and purified alpha toxin were included as controls. UAMS-1 does not produce alpha toxin and thus was not included in this experiment. *, a statistically significant difference by comparison to the results for the isogenic parent strain; **, a statistically significant difference by comparison to the results for the isogenic sarA mutant. (C and D) The relative amounts of eSpa (C) and alpha toxin (D) in LAC, its sarA and xerC mutants, and protease-deficient derivatives of each of these strains were assessed by Western blotting. *, a statistically significant difference between the results for the protease-deficient derivative and the isogenic protease-positive strain. Permutation-based ANOVA models were used to perform these analyses.