6M6K:
reference: Rational design of a reversible Mg(2+)/EDTA-controlled molecular switch based on a DNA minidumbbell., Wan L, Lam SL, Lee HK, Guo P, Chem Commun (Camb). 2020 Sep 1;56(70):10127-10130. doi: 10.1039/d0cc03774e. PMID: 32870195

This OCA Structure page
uses Jmol, developed by the Jmol Development Team (documentation).