A strategy for grafting protein-protein binding sites is described. Firstly, key interactionresidues at the interface of ligand protein to be grafted are identified and suitable positions in scaffold protein for grafting these key residues are sought. Secondly, the scaffold proteins are superposed onto the ligand protein based on the corresponding Cα and Cβ atoms. The complementarity between the scaffold protein and the receptor protein is evaluated and only matches with high score are accepted. The relative position between scaffold and receptor proteins is adjusted so that the interface has a reasonable packing density. Then the scaffold protein is mutated to corresponding residues in ligand protein at each candidate position. And the residues having bad steric contacts with the receptor proteins, or buried charged residues not involved in the formation of any salt bridge are mutated. Finally, the mutated scaffold protein in complex with receptor protein is co-minimized by Charmm. In addition, we de A. strategy for grafting protein-protein binding sites is described. Secondly, the key interactionresidues at the interface of ligand protein to be grafted are identified and suitable positions in scaffold protein for grafting these key residues are sought. ligand protein based on the corresponding Cα and Cβ atoms. The complementarity between the scaffold protein and the receptor protein is evaluated and only matches with high score are accepted. The relative position between scaffold and receptor proteins is adjusted so that the interface has a reasonable packing density the Then the scaffold protein is mutated to correspond residues in ligand protein at each candidate position. And the residues having bad steric contacts with the receptor proteins, or or buried charged residues not involved in the formation of any salt bridge are mutated. Finally, the mutated scaffold protein in complex with receptor protein is co-minimized by Charmm. In addition, we de