Part of the ABC transporter complex RbsABC involved in ribose import. Responsible for energy coupling to the transport system. ATP + D-ribose(out) + H2O = ADP + D-ribose(in) + H(+) + phosphate The complex is composed of an ATP-binding protein (RbsA), two transmembrane proteins (RbsC) and a solute-binding protein (RbsB). Belongs to the ABC transporter superfamily. Ribose importer (TC 3.A.1.2.1) family.