3C13:
reference: The catalytic subunit of human protein kinase CK2 structurally deviates from its maize homologue in complex with the nucleotide competitive inhibitor emodin., Raaf J, Klopffleisch K, Issinger OG, Niefind K, J Mol Biol. 2008 Mar 14;377(1):1-8. Epub 2008 Jan 11. PMID: 18242640

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