4KH2:
reference: Insights into mucopolysaccharidosis I from the structure and action of alpha-L-iduronidase., Bie H, Yin J, He X, Kermode AR, Goddard-Borger ED, Withers SG, James MN, Nat Chem Biol. 2013 Sep 11. doi: 10.1038/nchembio.1357. PMID: 24036510

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