Since H2O2 generation through Duox enzyme is a key mechanism for controlling pathogen load (55), we then tested which S. aureus antioxidant enzymes, catalase (katA encoded), superoxide dismutases (sodA and sodM encoded), or glutathione peroxidases (gpxA1 and gpxA2 encoded), might contribute to intestinal persistence during host infection. This evidence concerns the gene CAT and infection.