1OKJ:
reference: A complement to the modern crystallographer's toolbox: caged gadolinium complexes with versatile binding modes., Stelter M, Molina R, Jeudy S, Kahn R, Abergel C, Hermoso JA, Acta Crystallogr D Biol Crystallogr. 2014 Jun;70(Pt 6):1506-16. doi:, 10.1107/S1399004714005483. Epub 2014 May 23. PMID: 24914962

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