4E8V:
reference: Visualizing Group II Intron Catalysis through the Stages of Splicing., Marcia M, Pyle AM, Cell. 2012 Oct 26;151(3):497-507. doi: 10.1016/j.cell.2012.09.033. PMID: 23101623

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