title: Conservation of substrate specificities among coronavirus main proteases.
abstract: The key enzyme in coronavirus replicase polyprotein processing is the coronavirus main protease, 3CL(pro). The substrate specificities of five coronavirus main proteases, including the prototypic enzymes from the coronavirus groups I, II and III, were characterized. Recombinant main proteases of human coronavirus (HCoV), transmissible gastroenteritis virus (TGEV), feline infectious peritonitis virus, avian infectious bronchitis virus and mouse hepatitis virus (MHV) were tested in peptide-based trans-cleavage assays. The determination of relative rate constants for a set of corresponding HCoV, TGEV and MHV 3CL(pro) cleavage sites revealed a conserved ranking of these sites. Furthermore, a synthetic peptide representing the N-terminal HCoV 3CL(pro) cleavage site was shown to be effectively hydrolysed by noncognate main proteases. The data show that the differential cleavage kinetics of sites within pp1a/pp1ab are a conserved feature of coronavirus main proteases and lead us to predict similar processing kinetics for the replicase polyproteins of all coronaviruses.
authors.affiliation: Institute of Virology and Immunology, University of Würzburg, Versbacher Straße 7, 97078 Würzburg, Germany1.
authors.forename: Annette
authors.initials: A
authors.lastname: Hegyi
authors.affiliation: Institute of Virology and Immunology, University of Würzburg, Versbacher Straße 7, 97078 Würzburg, Germany1.
authors.forename: John
authors.initials: J
authors.lastname: Ziebuhr
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001717:Birds / Q000821:virology; D002415:Cats; D017934:Coronavirus / Q000145:classification / Q000201:enzymology*; D000086782:Coronavirus 3C Proteases; D003546:Cysteine Endopeptidases / Q000378:metabolism*; D019143:Evolution, Molecular; D006801:Humans; D006868:Hydrolysis; D007700:Kinetics; D051379:Mice; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D013379:Substrate Specificity; D013552:Swine / Q000821:virology
chemical_list: D010446:Peptide Fragments; D003546:Cysteine Endopeptidases; C000706208:3C-like proteinase, Avian infectious bronchitis virus; D000086782:Coronavirus 3C Proteases