ATPase component of the type IV secretion system Cag (Cag-T4SS) (PubMed:26565397). Acts as a molecular motor to provide the energy that is required for the export of proteins (Probable). Required for CagA translocation and induction of IL-8 in host gastric epithelial cells (PubMed:26565397, PubMed:8825091, PubMed:8962108). Plays a key role in Cag-T4SS pilus biogenesis, especially in the localization and stabilization of the pilus-associated components CagI, CagL and the surface protein CagH (PubMed:26565397). Is also critical for assembly of the entire cytoplasmic portion of the Cag inner membrane complex (IMC) (PubMed:31088930). ATP + H2O + cellular proteinSide 1 = ADP + phosphate + cellular proteinSide 2. Component of the Cag type IV secretion system, which is composed of a wheel-shaped outer membrane complex (OMC) and an inner membrane complex (IMC) (PubMed:31088930). Interacts with CagV and CagBeta (PubMed:26565397). Deletion of the gene affects pilus synthesis. Mutant is unable to translocate CagA and is unable to induce IL-8 secretion by gastric epithelial cells (PubMed:26565397). Deletion has no effect on assembly of the Cag outer membrane complex, but the mutant machine completely lacks the entire cytoplasmic complex (PubMed:31088930). Belongs to the TrbE/VirB4 family.