2NNX:
reference: Disease-associated mutations at copper ligand histidine residues of superoxide dismutase 1 diminish the binding of copper and compromise dimer stability., Wang J, Caruano-Yzermans A, Rodriguez A, Scheurmann JP, Slunt HH, Cao X, Gitlin J, Hart PJ, Borchelt DR, J Biol Chem. 2007 Jan 5;282(1):345-52. Epub 2006 Nov 8. PMID: 17092942

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