5U9M:
reference: Copper-zinc superoxide dismutase is activated through a sulfenic acid intermediate at a copper ion entry site., Fetherolf MM, Boyd SD, Taylor AB, Kim HJ, Wohlschlegel JA, Blackburn NJ, Hart PJ, Winge DR, Winkler DD, J Biol Chem. 2017 Jul 21;292(29):12025-12040. doi: 10.1074/jbc.M117.775981. Epub , 2017 May 22. PMID: 28533431

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