4UUJ:
reference: Structures of KcsA in Complex with Symmetrical Quaternary Ammonium Compounds Reveal a Hydrophobic Binding Site., Lenaeus MJ, Burdette D, Wagner T, Focia PJ, Gross A, Biochemistry. 2014 Aug 19;53(32):5365-73. doi: 10.1021/bi500525s. Epub 2014 Aug, 8. PMID: 25093676

This OCA Structure page
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