| 3JR3: reference: Structure-based mechanism of ADP-ribosylation by sirtuins., Hawse WF, Wolberger C, J Biol Chem. 2009 Nov 27;284(48):33654-61. Epub 2009 Sep 30. PMID: 19801667 |
This OCA 
Structure page
uses Jmol,
developed by the Jmol Development Team
(documentation).