3M4C:
reference: Structural characterization of a microperoxidase inside a metal-directed protein cage., Ni TW, Tezcan FA, Angew Chem Int Ed Engl. 2010 Sep 17;49(39):7014-8. PMID: 20721993

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