4ZYB:
reference: High resolution structure of an M23 peptidase with a substrate analogue., Grabowska M, Jagielska E, Czapinska H, Bochtler M, Sabala I, Sci Rep. 2015 Oct 6;5:14833. doi: 10.1038/srep14833. PMID: 26437833

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