Part of the Tol-Pal system, which plays a role in outer membrane invagination during cell division and is important for maintaining outer membrane integrity. The Tol-Pal system is also required for polar localization of chemoreceptors clusters. The system also appears to be required for the activity of several outer membrane-localized enzymes with cell wall remodeling activity. Is involved in the uptake of group A colicins (colicins A, E1, E2, E3, and K) and in the uptake of filamentous phage DNA