An ATPase (PubMed:26396239). Part of the ESX-1 specialized secretion system, which delivers several virulence factors to host cells during infection, including the key virulence factors EsxA (ESAT-6) and EsxB (CFP-10) (PubMed:16368961). Ca(2+) has 50% activity (PubMed:26396239). ATPase activity inhibited by EDTA (PubMed:26396239). kcat is 0.76 min (-1) for full-length protein, kcat is 0.11 min (-1) for residues 72-480. Oligomerizes, possibly a hexamer (PubMed:26396239). Part of the ESX-1 / type VII secretion system (T7SS), which is composed of cytosolic and membrane components. The ESX-1 membrane complex is composed of EccB1, EccCa1, EccCb1, EccD1 and EccE1. Residues 72-342 interact with an artificial EsxB-EsxA heterodimer (PubMed:19854905). Resides at or near the cell wall, the protein is susceptible to extracellular proteases (PubMed:26396239). Has a discontinuous central core of beta sheets stabilized by a disulfide bond that is flanked by 2 structural domain repeats on each side; the protein forms an elongated 'S'-shaped structure (PubMed:26396239, PubMed:26841765, PubMed:26922638). Repeat A2 (approximately residues 265-323) is farthest from the cell inner membrane and is quite mobile, swinging on 2 inter-repeat loops (A, residues 234-264 and B, 324-341) (PubMed:26841765). Disruption abolishes EsxA and EsxB secretion, but not their expression. It results in a lack of antigen specific immunogenicity and leads to attenuated virulence. Belongs to the EccB family.