FIG 2.

Effect of medium supplementation with Ca, the extracellular Ca chelator EGTA, or the intracellular Ca chelator BAPTA/AM on the twitching motility of WT X. fastidiosa. (A) Colony fringe widths of X. fastidiosa cultured on PW agar plates alone or supplemented with 2 mM CaCl₂, 1.5 mM EGTA, or 100 μm BAPTA. Different letters above the bars indicate statistically significant differences according to the GLIMMIX procedure (P ≤ 0.05). Error bars represent standard errors of the means (n = 36). (B) Assessment of twitching motility in microfluidic chambers after the addition of EGTA or BAPTA. The movement of the cells was recorded 14 h after chelator addition. The speed of the cells was calculated for each 2-h time lapse. Error bars at each point indicate the standard error of the mean (n = 4).