3NGD:
reference: Structural basis for proficient incorporation of dTTP opposite O6-methylguanine by human DNA polymerase iota., Pence MG, Choi JY, Egli M, Guengerich FP, J Biol Chem. 2010 Dec 24;285(52):40666-72. Epub 2010 Oct 20. PMID: 20961860

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