3CSK:
reference: The first structure of dipeptidyl-peptidase III provides insight into the catalytic mechanism and mode of substrate binding., Baral PK, Jajcanin-Jozic N, Deller S, Macheroux P, Abramic M, Gruber K, J Biol Chem. 2008 Aug 8;283(32):22316-24. Epub 2008 Jun 10. PMID: 18550518

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