5CKI:
reference: Crystal structure of a DNA catalyst., Ponce-Salvatierra A, Wawrzyniak-Turek K, Steuerwald U, Hobartner C, Pena V, Nature. 2016 Jan 14;529(7585):231-4. doi: 10.1038/nature16471. Epub 2016 Jan 6. PMID: 26735012

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