3U7R:
reference: The Structural and Functional Basis of Catalysis Mediated by NAD(P)H:acceptor Oxidoreductase (FerB) of Paracoccus denitrificans., Sedlacek V, Klumpler T, Marek J, Kucera I, PLoS One. 2014 May 9;9(5):e96262. doi: 10.1371/journal.pone.0096262. eCollection , 2014. PMID: 24817153

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