6WEY:
reference: Molecular Basis for ADP-Ribose Binding to the Mac1 Domain of SARS-CoV-2 nsp3., Frick DN, Virdi RS, Vuksanovic N, Dahal N, Silvaggi NR, Biochemistry. 2020 Jul 21;59(28):2608-2615. doi: 10.1021/acs.biochem.0c00309., Epub 2020 Jul 6. PMID: 32578982

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