6JIJ:
reference: The crystal structure of main protease from mouse hepatitis virus A59 in complex with an inhibitor., Cui W, Cui S, Chen C, Chen X, Wang Z, Yang H, Zhang L, Biochem Biophys Res Commun. 2019 Apr 16;511(4):794-799. doi:, 10.1016/j.bbrc.2019.02.105. Epub 2019 Mar 2. PMID: 30833083

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