3ZFJ:
reference: New Insights into Histidine Triad Proteins: Solution Structure of a Streptococcus pneumoniae PhtD Domain and Zinc Transfer to AdcAII., Bersch B, Bougault C, Roux L, Favier A, Vernet T, Durmort C, PLoS One. 2013 Nov 28;8(11):e81168. doi: 10.1371/journal.pone.0081168. PMID: 24312273

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