1OVV:
reference: Response of a designed metalloprotein to changes in metal ion coordination, exogenous ligands, and active site volume determined by X-ray crystallography., Geremia S, Di Costanzo L, Randaccio L, Engel DE, Lombardi A, Nastri F, DeGrado WF, J Am Chem Soc. 2005 Dec 14;127(49):17266-76. PMID: 16332076

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