title: The substrate specificity of SARS coronavirus 3C-like proteinase.
abstract: The 3C-like proteinase of severe acute respiratory syndrome coronavirus (SARS) has been proposed to be a key target for structural based drug design against SARS. We have designed and synthesized 34 peptide substrates and determined their hydrolysis activities. The conserved core sequence of the native cleavage site is optimized for high hydrolysis activity. Residues at position P4, P3, and P3' are critical for substrate recognition and binding, and increment of beta-sheet conformation tendency is also helpful. A comparative molecular field analysis (CoMFA) model was constructed. Based on the mutation data and CoMFA model, a multiply mutated octapeptide S24 was designed for higher activity. The experimentally determined hydrolysis activity of S24 is the highest in all designed substrates and is close to that predicted by CoMFA. These results offer helpful information for the research on the mechanism of substrate recognition of coronavirus 3C-like proteinase.
authors.affiliation: State Key Laboratory of Structural Chemistry of Stable and Unstable Species, College of Chemistry, Peking University, Beijing 100871, China.
authors.forename: Keqiang
authors.initials: K
authors.lastname: Fan
authors.forename: Liang
authors.initials: L
authors.lastname: Ma
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Han
authors.forename: Huanhuan
authors.initials: H
authors.lastname: Liang
authors.forename: Ping
authors.initials: P
authors.lastname: Wei
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.forename: Luhua
authors.initials: L
authors.lastname: Lai
mesh_terms: D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D001665:Binding Sites; D003198:Computer Simulation; D000086782:Coronavirus 3C Proteases; D003546:Cysteine Endopeptidases; D010450:Endopeptidases / Q000032:analysis* / Q000737:chemistry*; D004789:Enzyme Activation; D008956:Models, Chemical; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010455:Peptides / Q000032:analysis / Q000737:chemistry*; D011485:Protein Binding; D025941:Protein Interaction Mapping / Q000379:methods*; D013329:Structure-Activity Relationship; D013379:Substrate Specificity; D014764:Viral Proteins / Q000032:analysis* / Q000737:chemistry*
chemical_list: D010455:Peptides; D014764:Viral Proteins; D010450:Endopeptidases; D003546:Cysteine Endopeptidases; D000086782:Coronavirus 3C Proteases