Fig. 2.

YadB and YadC do not affect early survival of Y. pestis in systemic plague. Pgm⁻ Lcr⁺ Y. pestis strains CO92.S38 (ΔyadBC; open bars) and CO92.S42 (yadBC⁺ by restoration of the native yadBC operon; solid bars) were grown as indicated to induce expression of thermally regulated proteins 3 h prior to infecting mice by the intravenous route. Groups of mice were infected intravenously with doses ranging from 5×10³ to 10⁴ bacteria. After 3 h, the recovery of viable bacteria was determined in livers and spleens and is presented as the fraction of input c.f.u. that was recovered. The data for the 28 °C/37 °C_3h growth protocol are pooled from four replicate experiments, and each datum point represents the mean±sd for 14 mice. Two experiments were done for yersiniae grown at 37 °C, and each datum point represents the mean±sd of pooled data from seven mice.