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Gérard S, Raoul M, Sapi J. A New Approach to the Synthesis ofN-Alkylated 2-Substituted Azetidin-3-ones. European J Org Chem 2006. [DOI: 10.1002/ejoc.200500987] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Yin J, Bergmann EM, Cherney MM, Lall MS, Jain RP, Vederas JC, James MN. Dual modes of modification of hepatitis A virus 3C protease by a serine-derived beta-lactone: selective crystallization and formation of a functional catalytic triad in the active site. J Mol Biol 2005; 354:854-71. [PMID: 16288920 PMCID: PMC7118759 DOI: 10.1016/j.jmb.2005.09.074] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2005] [Revised: 09/22/2005] [Accepted: 09/23/2005] [Indexed: 12/30/2022]
Abstract
Hepatitis A virus (HAV) 3C proteinase is a member of the picornain cysteine proteases responsible for the processing of the viral polyprotein, a function essential for viral maturation and infectivity. This and its structural similarity to other 3C and 3C-like proteases make it an attractive target for the development of antiviral drugs. Previous solution NMR studies have shown that a Cys24Ser (C24S) variant of HAV 3C protein, which displays catalytic properties indistinguishable from the native enzyme, is irreversibly inactivated by N-benzyloxycarbonyl-l-serine-beta-lactone (1a) through alkylation of the sulfur atom at the active site Cys172. However, crystallization of an enzyme-inhibitor adduct from the reaction mixture followed by X-ray structural analysis shows only covalent modification of the epsilon2-nitrogen of the surface His102 by the beta-lactone with no reaction at Cys172. Re-examination of the heteronuclear multiple quantum coherence (HMQC) NMR spectra of the enzyme-inhibitor mixture indicates that dual modes of single covalent modification occur with a >/=3:1 ratio of S-alkylation of Cys172 to N-alkylation of His102. The latter product crystallizes readily, probably due to the interaction between the phenyl ring of the N-benzyloxycarbonyl (N-Cbz) moiety and a hydrophobic pocket of a neighboring protein molecule in the crystal. Furthermore, significant structural changes are observed in the active site of the 3C protease, which lead to the formation of a functional catalytic triad with Asp84 accepting one hydrogen bond from His44. Although the 3C protease modified at Cys172 is catalytically inactive, the singly modified His102 N(epsilon2)-alkylated protein displays a significant level of enzymatic activity, which can be further modified/inhibited by N-iodoacetyl-valine-phenylalanine-amide (IVF) (in solution and in crystal) or excessive amount of the same beta-lactone inhibitor (in solution). The success of soaking IVF into HAV 3C-1a crystals demonstrates the usefulness of this new crystal form in the study of enzyme-inhibitor interactions in the proteolytic active site.
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Affiliation(s)
- Jiang Yin
- CIHR Group in Protein Structure and Function, Department of Biochemistry, University of Alberta, Edmonton, Alta., Canada T6G 2H7
| | - Ernst M. Bergmann
- CIHR Group in Protein Structure and Function, Department of Biochemistry, University of Alberta, Edmonton, Alta., Canada T6G 2H7
- Alberta Synchrotron Institute, University of Alberta, Edmonton, Alta., Canada T6G 2E1
| | - Maia M. Cherney
- CIHR Group in Protein Structure and Function, Department of Biochemistry, University of Alberta, Edmonton, Alta., Canada T6G 2H7
| | - Manjinder S. Lall
- Department of Chemistry, University of Alberta, Edmonton, Alta., Canada T6G 2G2
| | - Rajendra P. Jain
- Department of Chemistry, University of Alberta, Edmonton, Alta., Canada T6G 2G2
| | - John C. Vederas
- Department of Chemistry, University of Alberta, Edmonton, Alta., Canada T6G 2G2
| | - Michael N.G. James
- CIHR Group in Protein Structure and Function, Department of Biochemistry, University of Alberta, Edmonton, Alta., Canada T6G 2H7
- Alberta Synchrotron Institute, University of Alberta, Edmonton, Alta., Canada T6G 2E1
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Jain RP, Pettersson HI, Zhang J, Aull KD, Fortin PD, Huitema C, Eltis LD, Parrish JC, James MNG, Wishart DS, Vederas JC. Synthesis and evaluation of keto-glutamine analogues as potent inhibitors of severe acute respiratory syndrome 3CLpro. J Med Chem 2005; 47:6113-6. [PMID: 15566280 DOI: 10.1021/jm0494873] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The 3C-like proteinase (3CL(pro)) of severe acute respiratory syndrome (SARS) coronavirus is a key target for structure-based drug design against this viral infection. The enzyme recognizes peptide substrates with a glutamine residue at the P1 site. A series of keto-glutamine analogues with a phthalhydrazido group at the alpha-position were synthesized and tested as reversible inhibitiors against SARS 3CL(pro). Attachment of tripeptide (Ac-Val-Thr-Leu) to these glutamine-based "warheads" generated significantly better inhibitors (4a-c, 8a-d) with IC(50) values ranging from 0.60 to 70 microM.
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Affiliation(s)
- Rajendra P Jain
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
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Jain RP, Vederas JC. Structural variations in keto-glutamines for improved inhibition against hepatitis A virus 3C proteinase. Bioorg Med Chem Lett 2004; 14:3655-8. [PMID: 15203137 DOI: 10.1016/j.bmcl.2004.05.021] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2004] [Revised: 05/11/2004] [Accepted: 05/12/2004] [Indexed: 11/23/2022]
Abstract
A series of keto-glutamine tetrapeptide analogs containing a 2-oxo-pyrrolidine ring as a glutamine side chain mimic were synthesized with both R and S configuration at the beta-carbon. Compounds bearing a phthalhydrazide moiety show improved reversible inhibition of HAV 3C proteinase in the low micromolar range.
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Affiliation(s)
- Rajendra P Jain
- Department of Chemistry, University of Alberta, Edmonton, AB, Canada T6G 2G2
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