FIG 5.

Twitching phenotypes of pilY1 mutant homologs. (A) Transmission electron micrograph of negatively stained pilY1-1611 mutant depicting both short type I pili and longer type IV pili (indicated by an asterisk). (B) Colony fringe widths of X. fastidiosa mutant strains cultured on unsupplemented PW agar or PW agar supplemented with 2 mM CaCl₂. Different letters above paired bars indicate statistically significant differences according to the GLIMMIX procedure (P ≤ 0.05). Error bars represent standard errors of the means (n = 12). (C) Assessments of the twitching speeds of cells incubated in unsupplemented PD2 medium or PD2 medium supplemented with 2 mM CaCl₂ in microfluidic chambers. Different letters above paired bars indicate significant differences according to the GLIMMIX procedure (P ≤ 0.05). Error bars represent standard errors of the means (n = 10). In panels B and C, the WT values are taken from reference 29 for comparative purposes.