Fig. 1.
The SARS-CoV Mpro dimer structure complexed with a substrate-analogue hexapeptidyl CMK inhibitor. (A) The SARS-CoV Mpro dimer structure is presented as ribbons, and inhibitor molecules are shown as ball-and-stick models. Protomer A (the catalytically competent enzyme) is red, protomer B (the inactive enzyme) is blue, and the inhibitor molecules are yellow. The N-finger residues of protomer B are green. The molecular surface of the dimer is superimposed. (B) A cartoon diagram illustrating the important role of the N-finger in both dimerization and maintenance of the active form of the enzyme.