Fig 5. Role of ryfA in the murine model of ascending UTI and in P fimbriae (pili) production.

(A) Adherence of strain CFT073 and its derivatives to human 5637 bladder epithelial cells in the presence or absence of 2.5% α-d-mannopyranose was determined. (B) Electron microscopy of CFT073 and the ΔryfA mutant. Arrows show fimbriae on cell surfaces. (C) Production of Pap fimbriae by hemagglutination assay. Results are the mean values and standard deviations for four biological experiments. (D) Single-strain infections to compare wild-type strain CFT073 to ΔryfA mutant. Results are presented as the log₁₀ CFU g⁻¹. Each data point represents a sample from an individual mouse, and horizontal bars indicate the medians. Two independent series of infections were performed: i (CFT073 WT and CFT073 ΔryfA) and ii (CFT073 WT and the complemented mutant). The ΔryfA mutant was attenuated 146-fold in bladder and 10,000-fold in kidneys compared to the WT parent strain. Data are means ± standard errors of the means of 10 mice. Statistical significance was calculated by one-way ANOVA (A and C) or Mann–Whitney Test (D): *, P < 0.05; **, P < 0.005; ***, P < 0.0001. NS, not significant.