Part of the ABC transporter FtsEX involved in cellular division. Forms a membrane-associated complex with FtsE. Transcription is modulated as a function of mycobacterial growth and division status, maximum expression being observed in log phase cells. May provide a basis for developing a marker to distinguish actively replicating M.tuberculosis cells from quiescent mycobacteria. Belongs to the ABC-4 integral membrane protein family. FtsX subfamily.