4E4E:
reference: Six-coordinate manganese(3+) in catalysis by yeast manganese superoxide dismutase., Sheng Y, Butler Gralla E, Schumacher M, Cascio D, Cabelli DE, Selverstone Valentine J, Proc Natl Acad Sci U S A. 2012 Sep 4;109(36):14314-9. Epub 2012 Aug 20. PMID: 22908245

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