This family is the C-terminal region of essential streptococcal FtsA proteins and their homologues. It acts as an intra-molecular switch, triggered by ATP, to promote polymerisation of the whole protein and to attach it to the membrane. FtsA is essential for the formation of the septum that divides fully-grown cells into two daughter cells at cell-division. FtsA anchors the constricting FtsZ ring to the membrane [1].

1: Role of the FtsA C terminus as a switch for polymerization and membrane association. Krupka M, Cabre EJ, Jimenez M, Rivas G, Rico AI, Vicente M; MBio. 2014;5:e02221. PMID:25425238