3FZD:
reference: Mutation of Asn28 disrupts the dimerization and enzymatic activity of SARS 3CL(pro) ., Barrila J, Gabelli SB, Bacha U, Amzel LM, Freire E, Biochemistry. 2010 May 25;49(20):4308-17. PMID: 20420403

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