1NCZ:
reference: X-ray structures of Mn, Cd and Tb metal complexes of troponin C., Rao ST, Satyshur KA, Greaser ML, Sundaralingam M, Acta Crystallogr D Biol Crystallogr. 1996 Sep 1;52(Pt 5):916-22. PMID: 15299599

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