2KXL:
reference: Structural insights into conformational changes of a cyclic nucleotide-binding domain in solution from Mesorhizobium loti K1 channel., Schunke S, Stoldt M, Lecher J, Kaupp UB, Willbold D, Proc Natl Acad Sci U S A. 2011 Apr 12;108(15):6121-6. Epub 2011 Mar 23. PMID: 21430265

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