4XJ2:
reference: Biochemical properties and crystal structure of the flavin reductase FerA from Paracoccus denitrificans., Sedlacek V, Klumpler T, Marek J, Kucera I, Microbiol Res. 2016 Jul-Aug;188-189:9-22. doi: 10.1016/j.micres.2016.04.006. Epub, 2016 Apr 27. PMID: 27296958

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