Extended Data Fig. 6. Characterization of FtsZ L169R and effect of filament properties on polarity sorting.
a, b, Interfilament distance of FtsZ WT (a) and FtsZ L169R (b) (n[WT] = 2, 2, 2 and 3 for 1.5, 3, 4 and 4.5 µM and n[L169R] = 5, 3 and 1 for 1.25, 2 and 3 µM). c, Height distribution of FtsZ WT and L169R filaments (n = 5 and 3 for FtsZ WT and L169R respectively).d-g, Effect of individual filament properties on the polarity sorting. In each plot, simulations with FtsZ WT are presented to be compared with simulations of FtsZ WT with one changed parameter. All studied properties decrease the polar sorting with persistence length having the smallest effect. Each plot represents averaged results over four packing fractions in range to ϕ = 0.29 to ϕ = 0.88. Lines represent the mean and the shaded area the 95% confidence interval. h, Polarity alignment of simulations with FtsZ WT and L169R in individual densities. The analysed simulations correspond to Fig. 6b. i, Quantification of FtsZ L169R membrane residence time by FRAP experiments. Dots represent individual experiments (n = 3, 6, 4 10, 6, 8, 3 and 4 for [FtsZ] = <0.6, 0.625, 0.9, 1.15, 1.25, 1.5, 2 and 3 µM). Boxes indicate the 25–75th percentiles, whiskers indicate the maximum/minimum values within the standard deviation and the midline shows the median. j, Quantification of Alexa488-FtsZ L169R TIRF intensities at increasing concentrations (n = 2 for each FtsZ concentration). k, Quantification of the GTPase hydrolysis rate of 5 µM FtsZ WT or L169R. The rates are 2.2 ± 0.03 and 0.78 ± 0.03 GTP/FtsZ/min respectively (mean ± s.d. p-value: 9.27*10-4, 2-tailed, equal variance t-test; n = 2). Lines represents the mean and the shaded area the standard deviation. l, TIRF micrographs and representative kymographs after differential imaging for FtsZ WT and L169R. Kymographs were obtained along the dashed lines. No directional polymerization is observed for L169R. Scale bars are 2 µm. m, Distribution of local curvatures in simulations of FtsZ L169R. Persistence length was extracted from variance of Gaussian function fitted to the data. n, Analysis of number of rings in simulations with FtsZ L169R using the same ring detection algorithm as for FtsZ WT (Extended Data Fig. 4i, j).