FIG 4.

Validation of Tn-seq hits as fitness factors in the traditional ascending UTI model. Ten CBA/J mice were transurethrally inoculated with 1 × 10⁸ CFU of UPEC, which consisted of a 1:1 mixture of wild-type CFT073 and an isogenic transposon mutant. Urine, bladder, and kidneys were collected at 48 hpi, and resulting homogenates were plated on LB agar with and without kanamycin to determine each contributing bacterial burden of the mutant and wild type, respectively. Each data point represents the log₁₀ competitive index calculated for individual mouse organ; each mouse is represented by a single color. Black lines indicate the median. A competitive index of 0 concludes that the wild-type and mutant have equal fitness. P values determined by the Wilcoxon signed-rank test are listed below.