Plays a role in the cell cycle. Involved in a late stage of septum formation leading to the separation of the daughter cells. Component of the septin complex composed of two copies of each spn1, spn2, spn3 and spn4. Localizes to the medial ring at the cell cortex of dividing cells. Belongs to the TRAFAC class TrmE-Era-EngA-EngB-Septin-like GTPase superfamily. Septin GTPase family.