In the pneumococcus cell division, MapZ (Midcell Anchored Protein Z) locates at the division site before FtsZ and guides septum positioning. MapZ forms ring structures at the cell equator and moves apart as the cell elongates, therefore behaving as a permanent beacon of division sites. MapZ then positions the FtsZ-ring through direct protein-protein interactions [1]. Structural analysis indicate that it displays a bi-modular structure composed of two subdomains separated by a flexible serine-rich linker. The extracellular C-terminal domain carries a conserved patch of amino acids which plays a crucial function in binding peptidoglycan and positioning MapZ at the cell equator [2].

1: MapZ marks the division sites and positions FtsZ rings in Streptococcus pneumoniae. Fleurie A, Lesterlin C, Manuse S, Zhao C, Cluzel C, Lavergne JP, Franz-Wachtel M, Macek B, Combet C, Kuru E, VanNieuwenhze MS, Brun YV, Sherratt D, Grangeasse C; Nature. 2014;516:259-262. PMID:25470041

2: Structure-function analysis of the extracellular domain of the pneumococcal cell\tdivision site positioning protein MapZ. Manuse S, Jean NL, Guinot M, Lavergne JP, Laguri C, Bougault CM, VanNieuwenhze MS, Grangeasse C, Simorre JP; Nat Commun. 2016;7:12071. PMID:27346279