Virulence of E. faecalis OG1RF and its isogenic pilin deletion mutants in experimental CAUTI. Twenty-four-hour viable bacterial titers in the bladders (A) and those associated with implants (B) from 2 to 4 independent experiments/strain are shown. Each shape corresponds to one mouse; open shapes represent nonpiliated bacterial strains. Median titers (CFU/bladder, CFU/implant) are shown with a bar: OG1RF (3.20 × 105, 6.25 × 104), EbpABC− strain (2.48 × 103, 7.00 × 102), EbpA− strain (3.10 × 103, 5.82 × 103), EbpB− strain (9.08 × 103, 1.50 × 104), EbpAB− strain (4.60 × 102, 50), EbpC− strain (5.80 × 104, 1.04 × 104), EbpBC− strain (5.00 × 102, 20), and EbpAC− strain (3.56 × 103, 40). Dashed lines are the limits of detection (10 CFU/bladder, 5 CFU/implant). Results of statistical comparisons of each mutant to OG1RF for bladders and implants are shown. There were no significant differences in bladder or implant colonization between any double pilin deletion mutant and the EbpABC− strain (data not shown). P values were adjusted for 10 comparisons (**, P < 0.01; ***, P < 0.001; ns, not significant).