Bacterial Cell Division

Abstract Bacterial cell division or cytokinesis is the process in which a bacterial cell is split into two progeny cells, each with a copy of the chromosome. In most bacteria this process in initiated by the formation of the Z ring, a dynamic structure consisting of polymers of FtsZ , a tublin family member. The Z ring recruits additional division proteins to form the septal ring, also called the divisome, which leads to the synthesis of the septum separating the progeny cells. Spatial regulation of Z‐ring formation occurs primarily through negative regulators of FtsZ assembly that are positioned within the cell. The Z ring forms where the concentration of these negative regulators is at a minimum. A variety of regulators and mechanisms for positioning them have been identified in different bacteria. Among the mechanisms are the binding of a regulator to the segregating chromosome or the divisome itself and a self‐organizing system. Key concepts: Division depends on a cytoskeletal element (Z ring) that functions as a scaffold to recruit all the division proteins. Spatial regulation of Z ring placement involves positioning inhibitors of FtsZ in the cell to prevent FtsZ polymers from coalescing into the ring. Dynamic self‐organization – the ability of proteins to form dynamic structures and patterns fuelled by nucleotide hydrolysis; the Min system produces an oscillatory pattern and FtsZ filaments have the ability to form rings when attached to a lipid bilayer that has a cylindrical shape.