5TXE:
reference: Structure of the Lasso Peptide Isopeptidase Identifies a Topology for Processing Threaded Substrates., Chekan JR, Koos JD, Zong C, Maksimov MO, Link AJ, Nair SK, J Am Chem Soc. 2016 Dec 21;138(50):16452-16458. doi: 10.1021/jacs.6b10389. Epub, 2016 Dec 7. PMID: 27998080

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