Fig 1.

Effect of the prc deletion on the ability of E. coli to induce bacteremia. (A) Independent infections of mice with WT-RS218 and Δprc-RS218. Blood counts were enumerated at 8 h postinfection. (B) trans-Complementation of Δprc-RS218 with the prc gene in independent infection experiments. pCL1920 is the empty vector, while pCL1920-prc is the vector harboring the prc gene. (C) Coinfection of mice with equal numbers of the otherwise wild-type strain L346 (the lacZ deletion mutant of RS218) and Δprc-RS218. Blood counts were differentiated and enumerated at 8 h postinfection on LB agar containing IPTG and X-Gal. (D) trans-Complementation of Δprc-RS218 with the prc gene in coinfection experiments. Equal numbers of L365 (the lacZ prc double-deletion mutant of RS218) harboring pCL1920 and Δprc-RS218 harboring pCL1920-prc were coinoculated into mice. P values for independent infections were determined by using the Mann-Whitney test, while those for coinfections were determined by using the Wilcoxon matched-pair test. *, P values of <0.05; **, P values of <0.01. Bars indicate the median level of the blood bacterial count. The dotted lines indicate the lower limit of detection.