Part of an ESX-3 / type VII specialized secretion system (T7SS), which exports several proteins. EccA3 exhibits ATPase activity and may provide energy for the export of ESX-3 substrates (By similarity). Part of the ESX-3 / type VII secretion system (T7SS), which is composed of cytosolic and membrane components (By similarity). Belongs to the CbxX/CfxQ family.