Component of the type II secretion system required for the energy-dependent secretion of extracellular factors such as proteases and toxins from the periplasm (PubMed:30346996). Plays a role in pseudopilus assembly and seems to control its length (PubMed:16012171). Interacts with the pseudopilus tip complex that is critical for the recognition and binding of secretion substrates (PubMed:19828448, PubMed:9466253). Type II pseudopilus confers increased bacterial adhesive capabilities (PubMed:12700254). Type II secretion is composed of four main components: the outer membrane complex, the inner membrane complex, the cytoplasmic secretion ATPase and the periplasm-spanning pseudopilus. Interacts with the tip of the type II pseudopilus subunits XcpV, XcpU and XcpW (PubMed:19828448, PubMed:30346996). Interacts with core component XcpT (PubMed:16012171). Cleaved by prepilin peptidase. Belongs to the GSP K family.