2KLS:
reference: Ca2+ regulation in the Na+/Ca2+ exchanger features a dual electrostatic switch mechanism., Hilge M, Aelen J, Foarce A, Perrakis A, Vuister GW, Proc Natl Acad Sci U S A. 2009 Aug 25;106(34):14333-8. Epub 2009 Aug 10. PMID: 19667209

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