6Y3Y:
reference: Cryo-EM structure of coronavirus-HKU1 haemagglutinin esterase reveals architectural changes arising from prolonged circulation in humans., Hurdiss DL, Drulyte I, Lang Y, Shamorkina TM, Pronker MF, van Kuppeveld FJM, Snijder J, de Groot RJ, Nat Commun. 2020 Sep 16;11(1):4646. doi: 10.1038/s41467-020-18440-6. PMID: 32938911

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