1Y97:
reference: The Human TREX2 3' -> 5'-Exonuclease Structure Suggests a Mechanism for Efficient Nonprocessive DNA Catalysis., Perrino FW, Harvey S, McMillin S, Hollis T, J Biol Chem 2005 Apr 15;280(15):15212-8. Epub 2005 Jan 19. PMID: 15661738

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