4IRM:
reference: Arginine 116 stabilizes the entrance to the metal ion-binding site of the MntC protein., Kanteev M, Adir N, Acta Crystallogr Sect F Struct Biol Cryst Commun. 2013 Mar 1;69(Pt 3):237-42., doi: 10.1107/S174430911300153X. Epub 2013 Feb 22. PMID: 23519795

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