Fig 7.

Levels of colonization of the cecum and colon by the wild-type EHEC 88-0643 and Δure mutant strains 7 days postinfection. BALB/c mice were inoculated with a 1:1 mixture of wild-type STEC 88-0643 and its isogenic Δure mutant. Seven days after inoculation, the cecums and colons were removed from the mice and the viable bacteria of each of the two strains associated with the tissues enumerated. The competitive index (CI) was calculated for both tissues, and the results of a Student two-tailed t test demonstrate that the mean CI is significantly different from 1, with P = 0.022 for the cecum. The P value for the colon was calculated to be 0.063; however, the CI was >1 for all mice in both the cecum and colon.