Involved in a multicomponent binding-protein-dependent transport system for glycine betaine. Probably responsible for energy coupling to the transport system. ATP + H2O + quaternary ammonium(out) = ADP + H(+) + phosphate + quaternary ammonium(in) The complex is composed of two ATP-binding proteins (OpuAA), two transmembrane proteins (OpuAB) and a solute-binding protein (OpuAC). Belongs to the ABC transporter superfamily.