4QED:
reference: Substrate Specificity of the Lanthipeptide Peptidase ElxP and the Oxidoreductase ElxO., Ortega MA, Velasquez JE, Garg N, Zhang Q, Joyce RE, Nair SK, van der Donk WA, ACS Chem Biol. 2014 Jun 6. PMID: 24866416

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