Fig. 4.

Deletion of rel impairs cellular attachment to BSA-coated polystyrene but not collagen, fibronectin, or ex vivo porcine heart valve tissue sections. For the experiments shown in panels (a–c), E. faecalis OG1RF, ∆rel and ∆rel∆relQ were grown in conditions known to induce in vitro expression of ace and efbA. Bacterial attachment to polystyrene wells that were (a) coated with BSA, (b) coated with collagen, or (c) coated with fibronectin was quantified by crystal violet staining and normalized by c.f.u. Each symbol represents one biological replicate. The horizontal bars show the mean. (a) Ordinary one-way ANOVA was used to determine whether the difference between the means of ∆rel or ∆rel∆relQ and OG1RF was statistically significant (P=0.0023). **, P=0.0011 by Dunnett’s multiple comparison post hoc test. (b, c) The differences in the means were not significant by one-way ANOVA. (d) The percentages of E. faecalis OG1RF, ∆rel and ∆rel∆relQ cells that attached to ex vivo porcine heart valve sections relative to the number of planktonic bacteria in the same well after 2 hours of incubation. Each symbol represents one biological replicate collected on a separate day. The horizontal bars show the mean. The means were not significantly different by statistical analysis (one-way ANOVA).