3CJA:
reference: Structural insight into signal conversion and inactivation by NTPDase2 in purinergic signaling., Zebisch M, Strater N, Proc Natl Acad Sci U S A. 2008 May 13;105(19):6882-7. Epub 2008 May 5. PMID: 18458329

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