FIG. 1.

Comparison of number of YPIIIpIB71 CFU recovered from the cecum, PP, and MLN of mice infected with a 3:1 ratio of WT Y. pseudotuberculosis to the Yop-deficient strain YPIIIpIB71 (mixed) with the number of CFU from mice infected with only YPIIIpIB71 at doses of 3 × 10⁸ (alone-low) and 3 × 10⁹ (alone-high). In the mixed infection experiment, a total of 3 × 10⁹ bacteria were used, of which 7.5 × 10⁸ were YPIIIpIB71. Four mice were infected with the mixed inoculum, and five mice were infected with the low and high doses of YPIIIpIB71. Mice were sacrificed 5 days postinfection.