4XHM:
reference: Rheostat re-wired: alternative hypotheses for the control of thioredoxin reduction potentials., Bewley KD, Dey M, Bjork RE, Mitra S, Chobot SE, Drennan CL, Elliott SJ, PLoS One. 2015 Apr 13;10(4):e0122466. doi: 10.1371/journal.pone.0122466., eCollection 2015. PMID: 25874934

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