Fig. 3.

Structural conservation analysis of M^proamong CoVs.

(a) Sequence alignment of M^pro from MHV-A59 and 7 various CoVs: HCoV-229E, HCoV-HKU1, HCoV-NL63, SARS-CoV, MERS-CoV, PEDV and IBV. (b) Superposition of M^pro from MHV-A59 and 7 various CoVs in complex with peptide substrate analogs (MHV-A59, green; HCoV-NL63, blue, PDB ID 5GWY; HCoV-HKU1, magenta, PDB ID 3D23; SARS-CoV, salmon, PDB ID 2AMQ; MERS-CoV, orange, PDB ID 5WKK; HCoV-229E, lime, PDB ID 2ZU2; PEDV, slate, PDB ID 5GWZ; IBV, yellow, PDB ID 2Q6F). (c) Surface representation of conserved substrate-binding pockets from various CoV M^pros. The background is MHV-A59 M^pro. Red: identical residues; orange: substitution in one CoV M^pro; magenta: substitution in two CoV M^pros; residues involved in N3 binding are shown as white sticks. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)