2FJT:
reference: Structure of the class IV adenylyl cyclase reveals a novel fold., Gallagher DT, Smith NN, Kim SK, Heroux A, Robinson H, Reddy PT, J Mol Biol. 2006 Sep 8;362(1):114-22. Epub 2006 Aug 14. PMID: 16905149

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