Effects of various kinetic rates of FtsZ filaments on bacterial cytokinesis.

Cell morphodynamics during bacterial cytokinesis are theoretically explored by a combination of phase field model for rod-shaped cells and a kinetic description for FtsZ ring maintenance. The division times and cell shapes have been generally decided by the competition between the constriction forces generated by FtsZ rings and the curvature elastic energy for cells. The dependences of cell morphodynamics during bacterial cytokinesis on various kinetic rates of FtsZ filaments are focused in the present study. It is found that the obtained results with the experimental parameters are well comparable to the observed results physiologically. Likewise, the quasi-steady states for FtsZ rings are found to be well consistent with the theoretical results derived from the kinetic description of FtsZ rings. In addition, morphological phase diagram is presented as functions of the membrane associate rate for both short FtsZ filaments and free FtsZ monomers, and the depolymerization rate of GDP-bound FtsZ monomers at the tip of filaments within the ring. Our results would provide a better understanding of the details of in vivo kinetics, including the kinetic rates within FtsZ rings.