4C2L:
reference: Crystal structure of Endo-Xylogalacturonan Hydrolase from Aspergillus tubingensis., Rozeboom HJ, Beldman G, Schols HA, Dijkstra BW, FEBS J. 2013 Sep 13. doi: 10.1111/febs.12524. PMID: 24034788

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