Cleavage specificity on synthetic peptide substrates of human rhinovirus 2 proteinase 2A

• Published in: The Journal of biological chemistry Vol. 267; no. 31; pp. 22639 - 22644
• Main Authors: SOMMERGRUBER, W, AHORN, H, ZÖPHEL, A, MAURER-FOGY, I, FESSL, F, SCHNORRENBERG, G, LIEBIG, H.-D, BLAAS, D, KUECHLER, E, SKERN, T
• Format: Journal Article
• Language: English
• Published: Bethesda, MD American Society for Biochemistry and Molecular Biology 05.11.1992
• Subjects: Amino Acid Sequence; Analytical, structural and metabolic biochemistry; Base Sequence; Biological and medical sciences; Cloning, Molecular; Cysteine Endopeptidases - metabolism; Enzymes and enzyme inhibitors; Escherichia coli; Fundamental and applied biological sciences. Psychology; Hydrogen-Ion Concentration; Hydrolases; Kinetics; Molecular Sequence Data; Oligodeoxyribonucleotides - chemistry; Peptides - chemistry; Peptides - metabolism; Protease Inhibitors - pharmacology; Recombinant Proteins - metabolism; Rhinovirus - enzymology; Sodium Chloride - pharmacology; Structure-Activity Relationship; Substrate Specificity; Viral Proteins; Virus; Human; Regulation(control); Enzymatic activity; Enzyme; Picornaviridae; Cleavage site; Rhinovirus 2; Kinetics; Rhinovirus
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1016/S0021-9258(18)41720-6

Proteinase 2A of human rhinovirus serotype 2 (HRV2 2A) was expressed in Escherichia coli and partially purified; the preparation was used to study various enzymatic parameters. Using a 16-amino acid peptide representing the native cleavage region of HRV2 2A, an apparent Km value of 5.4 x 10(-4) mol/liter was determined. A minimum of 9 amino acids (comprising residues P8 to P1') was necessary for cleavage to occur. Proteolysis of substituted peptides was highly tolerant toward changes at P1, P2', and P3' but an absolute requirement for glycine P1' and a high preference for threonine P2 was found. Furthermore, HRV2 2A only cleaved peptide substrates derived from other rhinovirus serotypes and poliovirus that possessed P2 Thr and P1' Gly. Thus, the sequence Thr-X-Gly may form the basis of the cellular cleavage site processed by rhinoviral 2As during viral replication. Studies with various inhibitors support the hypothesis that HRV2 2A belongs to a new class of cysteine proteinases.