The active sites of copper and zinc-containing superoxide dismutase ( CuZn-SOD) and Cu-SOD were extracted from spinach CuZn-SOD crystal structure as models. The quantum chemistry calculations on the models were performed by using Gaussian 94 with B3LYP/Lanl2DZ basis set to obtain information of molecular orbital energies, charges and atomic orbital contribution to the frontier molecular orbitals. The result indicates that copper plays an important role in catalyzing the O_2~- dismutation, zinc not only stabilizes the whole structure but also promotes organization of the active site structure.

Key words: SUPEROXIDE DISMUTASE;COPPER COMPOUNDS;ZINC COMPOUNDS;MOLECULAR ORBIT, SPINACH;TEMPLATE AGENT