1KQJ:
reference: Noncysteinyl coordination to the [4Fe-4S]2+ cluster of the DNA repair adenine glycosylase MutY introduced via site-directed mutagenesis. Structural characterization of an unusual histidinyl-coordinated cluster., Messick TE, Chmiel NH, Golinelli MP, Langer MR, Joshua-Tor L, David SS, Biochemistry 2002 Mar 26;41(12):3931-42. PMID: 11900536

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