Part of the binding-protein-dependent transport system for sn-glycerol-3-phosphate; probably responsible for the translocation of the substrate across the membrane. The complex is composed of two ATP-binding proteins (UgpC), two transmembrane proteins (UgpA and UgpE) and a solute-binding protein (UgpB). Belongs to the binding-protein-dependent transport system permease family. UgpAE subfamily.