FIG. 2.

Time course of colonization and persistence of Y. enterocolitica Δyop mutants and WA-C(pYV::CM) after oral infection of C57BL/6 mice with 10⁸ CFU. Two (A), five (B), seven (C), twelve (D), and twenty-one (E) days after infection, surviving bacteria in the SI (░⃞), PP (□), spleen (▪), and liver (▨) were determined. Values represent the average log CFU per organ for six mice with the standard errors of the means indicated by error bars. The limits of detection were 10 CFU/organ for PP and spleen and 50 CFU/organ for liver and SI. A “+” indicates that the strain was lethal for mice. Asterisks indicate statistical significance (P ≤ 0.05) between colonization of WA-C(pYV::CM) and the mutants.