Simulations of the 3D stochastic model of the Min system during cytokinesis. (

**A**) Schematic of the septum sizes and their corresponding simulation times used in the cytokinesis model. The times were calculated using the equation:

where

*d* is the septum size,

*D* is the cell width (1 μm), τ

_{c} is the time at which constriction starts (10 min) and τ

_{g} is the time between successive divisions (30 min). (

**B**) Results of one simulation of the cytokinesis model showing the number of MinD molecules in each polar region as a function of time. Colors and symbols are as in . (

**C**) Absolute value of the difference (

*dfc*) between molecule numbers of MinD (diamonds) or of a cytoplasmic protein (squares) in the virtual daughter cells during cytokinesis. Means were calculated over 11 independent simulations. Error bars represent the s.e.m. (

**D**) Equilibration of MinE, plotted as in (C). (

**E**) Table showing the relation between diffusion coefficient and oscillatory regime obtained in the simulations of a cell with the indicated septum size. In red, default diffusion coefficient. Five independent simulations of 2000 s were run for each diffusion coefficient value. (

**F**) FRAP analysis for HtpG–EYFP fusion performed on unconstricted (open diamonds) and constricted (filled squares) cells (see Materials and methods). MG1655 cells carrying the plasmid for the expression of the fusion protein were induced at early exponential growth phase with 100 μM IPTG for 3 h. Curves show the fluorescence recovery averaged over 20 unconstricted or constricted cells of similar mean length (4.8 and 5 μm, respectively). Source data is available for this figure at www.nature.com/msb.

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