SODC CU. en ribbon and surface model of human cytoplasmic superoxid dismutase SODC dimer with Zn black and Cu blue ions from PDB CU Ref Strange et al Variable Metallation of Human Superoxide Dismutase Atomic Resolution Crystal Structures of CuZn ZnZn and Asisolated Wildtype Enzymes Mol Biol PMID DOI jmb adapted from pdb