Fig. 1

Colonization levels in BXD parental strains after infection with STEC O157:H7 strains. B6 and D2 strains were infected with isogenic O157:H7 strains 86–24 (Stx2a+) (a) or TUV86-2 (Stx-) (b). Individual mouse colonization levels are depicted as CFU/g feces over the course of the experiment and the black bars represent the geometric mean of the group. (*) The difference in colonization levels between B6 and D2 mice was significant after infection with TUV86-2 on days 3 and 4 as D2 mice maintained colonization while B6 showed reduced colonization or even cleared the infection (P ≤ 0.003). n = 10. Limit of detection was 10² CFU/g