2ATK:
reference: Molecular determinants of gating at the potassium-channel selectivity filter., Cordero-Morales JF, Cuello LG, Zhao Y, Jogini V, Cortes DM, Roux B, Perozo E, Nat Struct Mol Biol. 2006 Apr;13(4):311-8. Epub 2006 Mar 12. PMID: 16532009

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