Cobalt hexamine trichloride induced toroidal condensation of FtsZ

Abstract

The bacterial cell division protein, FtsZ, polymerizes to form a cytokinetic Z-ring at the midcell, which engineers bacterial cell division. Herein, we have examined the effects of an inorganic polyamine, cobalt hexamine trichloride, on the assembly of FtsZ <i style="">in vitro</i>. Cobalt hexamine trichloride strongly enhances FtsZ assembly, suppresses its GTPase activity and stabilizes FtsZ polymers. However, CoCl₂and MnCl₂have no detectable effect on the assembly of FtsZ <i style="">in vitro</i>. Interestingly, FtsZ is found to assemble into toroidal structures in the presence of low concentrations of cobalt hexamine trichloride. The Z-ring in bacterial cells appears to be a toroidal-like structure, suggesting that the use of cobalt hexamine trichloride may help to understand the assembly of FtsZ into toroidal structure. The toroidal structures may also serve as templates to build toroidal resonators for electrical and thermal applications.