3TWM:
reference: Structural and biochemical studies of a plant formamidopyrimidine-DNA glycosylase reveal why eukaryotic Fpg glycosylases do not excise 8-oxoguanine., Duclos S, Aller P, Jaruga P, Dizdaroglu M, Wallace SS, Doublie S, DNA Repair (Amst). 2012 Jul 10. PMID: 22789755

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