... cleavage of the c-phosphate does occur in the NBD with the mutation at the IC [36,38,39]. More-over, these and other studies suggest that the ICresidues are involved in the formation of the NBDdimer, ... explanation for the inactivation of the catalytic activity with augmentation of affinity for ATPat NBD1 would be that this could maintain the NBDsin a closed dimer for longer, thus allowing the channelto ... respon-sible for coordinating the essential Mg2+cofactor[22,24,25], the signature sequence contacts the c-phosphate of the bound nucleotide across the dimer [15] and the aromatic residue of the...