5KBK:
reference: The Phylogeny and Active Site Design of Eukaryotic Cu-only Superoxide Dismutases., Peterson RL, Galaleldeen A, Villarreal J, Taylor AB, Cabelli DE, Hart PJ, Culotta VC, J Biol Chem. 2016 Aug 17. pii: jbc.M116.748251. PMID: 27535222

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