3U87:
reference: Low-density crystal packing of human protein kinase CK2 catalytic subunit in complex with resorufin or other ligands: a tool to study the unique hinge-region plasticity of the enzyme without packing bias., Klopffleisch K, Issinger OG, Niefind K, Acta Crystallogr D Biol Crystallogr. 2012 Aug;68(Pt 8):883-92. Epub 2012 Jul 7. PMID: 22868753

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