4HI3:
reference: Mechanism for controlling the monomer-dimer conversion of SARS coronavirus main protease., Wu CG, Cheng SC, Chen SC, Li JY, Fang YH, Chen YH, Chou CY, Acta Crystallogr D Biol Crystallogr. 2013 May;69(Pt 5):747-55. doi:, 10.1107/S0907444913001315. Epub 2013 Apr 11. PMID: 23633583

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