3FRP:
reference: The Crystal Structure of Cobra Venom Factor, a Cofactor for C3- and C5-Convertase CVFBb., Krishnan V, Ponnuraj K, Xu Y, Macon K, Volanakis JE, Narayana SV, Structure. 2009 Apr 15;17(4):611-9. PMID: 19368894

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