CLPP and infection: Despite the essential role of ClpP for S. aureus virulence in animal models of infection (48, 55, –, 57), mutations in the clpP gene on multiple occasions have been identified in S. aureus strains isolated from patients undergoing treatment with daptomycin or vancomycin, raising the question of how S. aureus benefits from mutations in the ClpP protease in patients treated with these last-line antibiotics.