INTERACTION OF COPPER IN CUZN-SUPEROXIDE DISMUTASE WITH HISTIDINE

The interaction of CuZn-superoxide dismutase ( CuZn-SOD ) with the external histidine in aqueous solution has been studied in this work by ESR and NMR. It is found that the Cu(II) of CuZn-SOD makes an exchanging interaction with the external substance in aqueous solution. Unlike in solid state, the Cu (II) forms complex with external histidine, and keeps a motional equilibrium between the active centers and the complexes. Enzyme activity is also affected by this interaction. Some other amino acids are also discussed in this paper.