CTRL and infection: This has shown that inoculation with C. rodentium expressing TirP5A, TirY451A, TirY471A and TirY451A/Y471A (Fig. 3A) resulted in the same colonization dynamics as wild-type C. rodentium or the control strains expressing TirN-ctrl and TirC-ctrl (Fig. 3A); infection with all strains peaked at day 7 and started to clear from day 15 post inoculation.