Essential cell division protein that forms a contractile ring structure (Z ring) at the future cell division site. The regulation of the ring assembly controls the timing and the location of cell division. One of the functions of the FtsZ ring is to recruit other cell division proteins to the septum to produce a new cell wall between the dividing cells. Binds GTP and shows GTPase activity. Polymerization and bundle formation is enhanced by CbeA. Formation of the FtsZ ring is inhibited by SulA, MinCD, DicB and toxins CbtA and CptA. Inhibition by toxin CbtA, SulA or DicB overexpression is neutralized by cytoskeleton bundling-enhancing protein CbeA, while inhibition by toxin CptA is neutralized by antitoxin CptB (PubMed:21166897, PubMed:22239607, PubMed:22515815, PubMed:8752322). Either FtsA or ZipA is required for Z ring formation and stabilization (PubMed:11847116). Homodimer. Polymerizes to form a dynamic ring structure in a strictly GTP-dependent manner. Polymers persist as long as GTP is present and disappear rapidly as soon as it is consumed. Interacts directly with several other division proteins, including FtsA and ZipA. Interacts with polymerization inhibitors SulA, CbtA and CptA. Interacts with MreB and polymerization bundling-enhancing factor CbeA. Interacts with CbtA, YkfI and YpjF (PubMed:28257056). Assembles in a ring-like structure at midcell at the inner surface of the cytoplasmic membrane. Repressed 1.3-fold by hydroxyurea (at protein level). The central and C-terminal regions are required for dimerization. (Microbial infection) ADP-ribosylated on Arg-174 and sometimes Arg-338 by Tre1 when infected by S.proteamaculans strain 568. This prevents the formation of Z rings, inhibiting cell division, leading to cell elongation and disadvantaging E.coli over S.proteamaculans during competition for nutrients. In vitro it can be de-ADP-ribosylated by S.proteamaculans Tri1. Belongs to the FtsZ family. Becoming two - Issue 171 of July 2015