savRS mutant strain displays enhanced virulence in the mouse abscess infection model. (A) Mice were injected subcutaneously with 5 × 107 cells. Abscess areas were measured daily. *, P < 0.05; **, P < 0.01; ***, P < 0.001. (B) Representative abscesses at 7 days after infection. (C) The abscesses were harvested at 7 days, and the number of CFU recovered from each abscess was determined. ***, P < 0.001. (D) Representative histological results (H&E stain).