2HOB:
reference: Production of authentic SARS-CoV M(pro) with enhanced activity: application as a novel tag-cleavage endopeptidase for protein overproduction., Xue X, Yang H, Shen W, Zhao Q, Li J, Yang K, Chen C, Jin Y, Bartlam M, Rao Z, J Mol Biol. 2007 Feb 23;366(3):965-75. Epub 2006 Dec 1. PMID: 17189639

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