3WH1:
reference: Crystal structure of a "loopless" GH19 chitinase in complex with chitin tetrasaccharide spanning the catalytic center., Ohnuma T, Umemoto N, Nagata T, Shinya S, Numata T, Taira T, Fukamizo T, Biochim Biophys Acta. 2014 Feb 25;1844(4):793-802. doi:, 10.1016/j.bbapap.2014.02.013. PMID: 24582745

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