Shows ATPase activity. Could provide energy for export of ESX-2 substrates (By similarity). Part of the ESX-2 / type VII secretion system (T7SS), which is composed of cytosolic and membrane components (By similarity). Residues 522-619 interact with an artificial EsxB-EsxA heterodimer from the adjacent ESX-1 locus (PubMed:19854905). Belongs to the CbxX/CfxQ family.