Fig. 7.
Surface representation of mesonivirus and coronavirus 3CLpro substrate-binding sites using (a) the structure of the CavV 3CLpro/inhibitor complex (PDB ID: 5LAK; pink) and (b) the structure of TGEV 3CLpro in a complex with a peptidic inhibitor (Anand et al., 2003) (PDB ID: 1P9U; light blue). Ligands are represented as sticks and color-coded by atom types. Amino acids involved in substrate binding are shown as lines and color-coded by atom types. Catalytic residues and the conserved His residue in the S1 subsite are indicated (see text for details).