1XOB:
reference: High-resolution solution structures of oxidized and reduced Escherichia coli thioredoxin., Jeng MF, Campbell AP, Begley T, Holmgren A, Case DA, Wright PE, Dyson HJ, Structure 1994 Sep 15;2(9):853-68. PMID: 7812718

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