4WBB:
reference: Single Turnover Autophosphorylation Cycle of the PKA RIIbeta Holoenzyme., Zhang P, Knape MJ, Ahuja LG, Keshwani MM, King CC, Sastri M, Herberg FW, Taylor SS, PLoS Biol. 2015 Jul 9;13(7):e1002192. doi: 10.1371/journal.pbio.1002192., eCollection 2015 Jul. PMID: 26158466

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