FIG 3.

The role of ClpP1 and ClpP2 in swimming and twitching. (A) Swimming is controlled by ClpP1 and, to a lesser extent, ClpP2. Plates were grown ∼16 h at 30°C and motility measured directly with a NIST traceable ruler. Values are normalized averages (n = 6) ± 1 standard error of the mean (SEM). Data were compared to control values (WT) by analysis of variance (ANOVA) with Dunnett's post hoc test (***, P < 0.0001; NS, not significant). Images are representative examples for display purposes only and acquired as described in Materials and Methods. (B) Twitching motility is controlled by ClpP1 but not ClpP2. Plates were incubated ∼48 h at room temperature and dyed with crystal violet. Twitching was quantitated, reported, and displayed as described for swimming. Nonmotile strains lacking either flagella (ΔfliC mutant) or pili (ΔpilA mutant) were used as negative controls.