Part of an ABC transporter complex involved in tungstate uptake. Probably responsible for energy coupling to the transport system. ATP + H2O + tungstate(in) = ADP + H(+) + phosphate + tungstate(out) The complex is composed of two ATP-binding proteins (TupC), two transmembrane proteins (TupB) and a solute-binding protein (TupA). Belongs to the ABC transporter superfamily.