Inhibition of the Bovine Viral Diarrhoea Virus NS3 Serine Protease by a Boron-Modified Peptidyl Mimetic of its Natural Substrate

• Published in: Antiviral chemistry & chemotherapy Vol. 12; no. 6; pp. 367 - 373
• Main Authors: Bukhtiyarova, Marina, Rizzo, Christopher J, Kettner, Charles A, Korant, Bruce D, Scarnati, Helen T, King, Robert W
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01.11.2001; International Medical Press; Sage Publications Ltd
• Subjects: Alanine; Animals; Antibiotics. Antiinfectious agents. Antiparasitic agents; Antiviral activity; Antiviral agents; Binding, Competitive; Biological and medical sciences; Blotting, Western; Boron; Boron - chemistry; Cattle; Cell Line; Diarrhea; Diarrhea Viruses, Bovine Viral - drug effects; Diarrhea Viruses, Bovine Viral - enzymology; Diarrhea Viruses, Bovine Viral - genetics; Diarrhea Viruses, Bovine Viral - physiology; Dose-Response Relationship, Drug; Drug development; Heparin; Hepatitis C; Leucine; Medical sciences; Molecular Mimicry; Peptides - chemistry; Peptides - pharmacology; Permeability; Pharmacology. Drug treatments; Protein Processing, Post-Translational - drug effects; Proteinase; Serine; Serine Endopeptidases - isolation & purification; Serine Endopeptidases - metabolism; Serine proteinase; Serine Proteinase Inhibitors - chemistry; Serine Proteinase Inhibitors - pharmacology; Virus Replication - drug effects; protease; BVDV; peptidyl mimetic; antiviral; NS3; Pestivirus; Purification; Enzyme; Peptidomimetic compound; Enzyme inhibitor; Gene expression; Virus; Boric acid; Peptidases; Analog; Bovine diarrhea virus; Hydrolases; Flaviviridae; Chemical synthesis
• ISSN: 2040-2066; 0956-3202; 2040-2066
• DOI: 10.1177/095632020101200607

Bovine viral diarrhoea virus (BVDV) is closely related to hepatitis C virus (HCV), and has been used as a surrogate virus in drug development for HCV infection. Similar to HCV, BVDV-encoded NS3 serine proteinase is responsible for multiple cleavages in the viral polyprotein, generating mature NS4A, NS4B, NS5A and NS5B proteins. NS3-dependent cleavage sites of BVDV contain a strictly conserved leucine at P1, and either serine or alanine at P1′. The full length BVDV NS3/4A serine protease has been cloned and expressed in bacterial cells. The enzyme has been purified from the soluble portion of Escherichia coli via a two-step purification procedure employing chromatography on heparin resin and gel filtration. The protease activity was characterized using in vitro translated BVDV NS4A/B and NS5A/B polyprotein substrates. A boronic acid analogue of the BVDV NS4A/NS4B cleavage site was synthesized and shown to be an efficient inhibitor of the NS3 serine protease in vitro. The compound, designated DPC-AB9144–00, inhibited approximately 75% of the NS3/4 activity at 10 μM with the NS4A/B substrate. However, no antiviral activity was detected with DPC-AB9144–00 in BVDV-infected Madin—Darby bovine kidney cells at concentrations as great as 90 μM, suggesting permeability or that other cellular-derived limitations were present.