4ZN0:
reference: Crystal Structure of the Apo-Form of NADPH-Dependent Thioredoxin Reductase from a Methane-Producing Archaeon., Buey RM, Schmitz RA, Buchanan BB, Balsera M, Antioxidants (Basel). 2018 Nov 17;7(11). pii: antiox7110166. doi:, 10.3390/antiox7110166. PMID: 30453601

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