5T5M:
reference: The methanogenic CO2 reducing-and-fixing enzyme is bifunctional and contains 46 [4Fe-4S] clusters., Wagner T, Ermler U, Shima S, Science. 2016 Oct 7;354(6308):114-117. PMID: 27846502

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