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Zainal Abidin A, Norrrahim MNF, Mohamed Shakrin NNS, Ibrahim B, Abdullah N, Abdul Rashid JI, Mohd Kasim NA, Ahmad Shah NA. Amidine containing compounds: Antimicrobial activity and its potential in combating antimicrobial resistance. Heliyon 2024; 10:e32010. [PMID: 39170404 PMCID: PMC11336351 DOI: 10.1016/j.heliyon.2024.e32010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2023] [Revised: 05/24/2024] [Accepted: 05/27/2024] [Indexed: 08/23/2024] Open
Abstract
Antimicrobial resistance (AMR) is a growing and concerning threat to global public health, necessitating innovative strategies to combat this crisis. Amidine-containing compounds have emerged as promising agents in the battle against AMR. This review gives a summary of recent advances from the past decade in studies of antimicrobial amidine-containing compounds with the aim to feature their structural diversity and the pharmacological relevance of the moiety to antimicrobial activity and their potential use in combating antimicrobial resistance, to the greatest extent possible. Highlighting is put on chemical structure of such compounds in relation to antimicrobial activities such as antibacterial, antifungal, and antiparasitic activities. Researchers commonly modify molecules containing amidine or incorporate amidine into existing antimicrobial agents to enhance their pharmacological attributes and combat antimicrobial resistance. This comprehensive review consolidates the current knowledge on amidine-containing compounds, elucidating their antimicrobial mechanisms and highlighting their promise in addressing the global AMR crisis. By offering a multidisciplinary perspective, we aim to inspire further research and innovation in this critical area of antimicrobial research.
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Affiliation(s)
- Asmaa Zainal Abidin
- Department of Chemistry and Biology, Centre for Defence Foundation Studies, Universiti Pertahanan Nasional Malaysia, Kem Perdana Sungai Besi, 57000 Kuala Lumpur, Malaysia
| | - Mohd Nor Faiz Norrrahim
- Research Centre for Chemical Defence, Universiti Pertahanan Nasional Malaysia, Kem Perdana Sungai Besi, 57000 Kuala Lumpur, Malaysia
| | | | - Baharudin Ibrahim
- Faculty of Pharmacy, Universiti Malaya, 50603 Kuala Lumpur, Malaysia
| | - Norli Abdullah
- Department of Chemistry and Biology, Centre for Defence Foundation Studies, Universiti Pertahanan Nasional Malaysia, Kem Perdana Sungai Besi, 57000 Kuala Lumpur, Malaysia
| | - Jahwarhar Izuan Abdul Rashid
- Department of Chemistry and Biology, Centre for Defence Foundation Studies, Universiti Pertahanan Nasional Malaysia, Kem Perdana Sungai Besi, 57000 Kuala Lumpur, Malaysia
| | - Noor Azilah Mohd Kasim
- Department of Chemistry and Biology, Centre for Defence Foundation Studies, Universiti Pertahanan Nasional Malaysia, Kem Perdana Sungai Besi, 57000 Kuala Lumpur, Malaysia
| | - Noor Aisyah Ahmad Shah
- Department of Chemistry and Biology, Centre for Defence Foundation Studies, Universiti Pertahanan Nasional Malaysia, Kem Perdana Sungai Besi, 57000 Kuala Lumpur, Malaysia
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Oztug M, Durer ZAO, Yetke Hİ, Asicioglu M, Akgoz M, Karaguler NG. Cloning, Expression, and Characterization of Serine Protease AprX from Geobacillus thermoleovorans ARTRW1. Ind Biotechnol (New Rochelle N Y) 2022. [DOI: 10.1089/ind.2022.0016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Merve Oztug
- Department of Molecular Biology and Genetics, Faculty of Science and Letters, Istanbul Technical University, Istanbul, Turkey
- Dr. Orhan Öcalgiray Molecular Biology-Biotechnology and Genetics Research Center, Istanbul Technical University, Istanbul, Turkey
- TUBITAK National Metrology Institute (TUBITAK UME), Kocaeli, Turkey
| | - Zeynep A. Oztug Durer
- Department of Biophysics, School of Medicine, Acıbadem Mehmet Ali Aydinlar University, Istanbul, Turkey
- Department of Biochemistry, School of Pharmacy, Acıbadem Mehmet Ali Aydinlar University, Istanbul, Turkey
| | - Hande İpek Yetke
- Department of Biophysics, Faculty of Medicine, Marmara University, Istanbul, Turkey
| | - Meltem Asicioglu
- Department of Molecular Biology and Genetics, Faculty of Science and Letters, Istanbul Technical University, Istanbul, Turkey
- Dr. Orhan Öcalgiray Molecular Biology-Biotechnology and Genetics Research Center, Istanbul Technical University, Istanbul, Turkey
- TUBITAK National Metrology Institute (TUBITAK UME), Kocaeli, Turkey
| | - Muslum Akgoz
- TUBITAK National Metrology Institute (TUBITAK UME), Kocaeli, Turkey
| | - Nevin Gul Karaguler
- Department of Molecular Biology and Genetics, Faculty of Science and Letters, Istanbul Technical University, Istanbul, Turkey
- Dr. Orhan Öcalgiray Molecular Biology-Biotechnology and Genetics Research Center, Istanbul Technical University, Istanbul, Turkey
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3
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A novel FRET peptide assay reveals efficient Helicobacter pylori HtrA inhibition through zinc and copper binding. Sci Rep 2020; 10:10563. [PMID: 32601479 PMCID: PMC7324608 DOI: 10.1038/s41598-020-67578-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Accepted: 06/09/2020] [Indexed: 12/21/2022] Open
Abstract
Helicobacter pylori (H. pylori) secretes the chaperone and serine protease high temperature requirement A (HtrA) that cleaves gastric epithelial cell surface proteins to disrupt the epithelial integrity and barrier function. First inhibitory lead structures have demonstrated the essential role of HtrA in H. pylori physiology and pathogenesis. Comprehensive drug discovery techniques allowing high-throughput screening are now required to develop effective compounds. Here, we designed a novel fluorescence resonance energy transfer (FRET) peptide derived from a gel-based label-free proteomic approach (direct in-gel profiling of protease specificity) as a valuable substrate for H. pylori HtrA. Since serine proteases are often sensitive to metal ions, we investigated the influence of different divalent ions on the activity of HtrA. We identified Zn++ and Cu++ ions as inhibitors of H. pylori HtrA activity, as monitored by in vitro cleavage experiments using casein or E-cadherin as substrates and in the FRET peptide assay. Putative binding sites for Zn++ and Cu++ were then analyzed in thermal shift and microscale thermophoresis assays. The findings of this study will contribute to the development of novel metal ion-dependent protease inhibitors, which might help to fight bacterial infections.
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Oh SB, Kim JA, Park S, Lee JY. Associative Interactions among Zinc, Apolipoprotein E, and Amyloid-β in the Amyloid Pathology. Int J Mol Sci 2020; 21:ijms21030802. [PMID: 31991844 PMCID: PMC7037199 DOI: 10.3390/ijms21030802] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 01/23/2020] [Accepted: 01/23/2020] [Indexed: 01/06/2023] Open
Abstract
Zinc and apolipoprotein E (apoE) are reportedly involved in the pathology of Alzheimer's disease. To investigate the associative interaction among zinc, apoE, and amyloid-β (Aβ) and its role in amyloid pathogenesis, we performed various biochemical and immunoreactive analyses using brain tissues of Tg2576 mice and synthetic Aβ and apoE peptides. On amyloid plaques or in brain lysates of Tg2576 mice, apoE and Aβ immunoreactivities increased after zinc chelation and were restored by its subsequent replacement. Zinc depletion dissociated apoE/Aβ complexes or larger-molecular sizes of Aβ oligomers/aggregates into smaller-molecular sizes of apoE and/or Aβ monomers/complexes. In the presence of zinc, synthetic apoE and/or Aβ peptides aggregated into larger-molecular sizes of oligomers or complexes. Endogenous proteases or plasmin in brain lysates degraded apoE and/or Aβ complexes, and their proteolytic activity increased with zinc depletion. These biochemical findings suggest that zinc associates with apoE and Aβ to encourage the formation of apoE/Aβ complexes or large aggregates, raising the deposition of zinc-rich amyloid plaques. In turn, the presence of abundant zinc around and within apoE/Aβ complexes may block the access or activity of Aβ-degrading antibodies or proteases. These results support the plausibility of chelation strategy aiming at reducing amyloid pathology in Alzheimer's disease.
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Affiliation(s)
- Shin Bi Oh
- Asan Institute for Life Sciences, Asan Medical Center, Seoul 05505, Korea; (S.B.O.); (J.A.K.); (S.P.)
| | - Jung Ah Kim
- Asan Institute for Life Sciences, Asan Medical Center, Seoul 05505, Korea; (S.B.O.); (J.A.K.); (S.P.)
| | - SuJi Park
- Asan Institute for Life Sciences, Asan Medical Center, Seoul 05505, Korea; (S.B.O.); (J.A.K.); (S.P.)
- Department of Medical Science, Asan Medical Institute of Convergence Science and Technology, University of Ulsan College of Medicine, Seoul 05505, Korea
| | - Joo-Yong Lee
- Asan Institute for Life Sciences, Asan Medical Center, Seoul 05505, Korea; (S.B.O.); (J.A.K.); (S.P.)
- Department of Convergence Medicine, University of Ulsan College of Medicine, Seoul 05505, Korea
- Correspondence: ; Tel.: +82-2-3010-4143; Fax: +82-2-3010-4680
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Meanwell NA. 2015 Philip S. Portoghese Medicinal Chemistry Lectureship. Curing Hepatitis C Virus Infection with Direct-Acting Antiviral Agents: The Arc of a Medicinal Chemistry Triumph. J Med Chem 2016; 59:7311-51. [PMID: 27501244 DOI: 10.1021/acs.jmedchem.6b00915] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The development of direct-acting antiviral agents that can cure a chronic hepatitis C virus (HCV) infection after 8-12 weeks of daily, well-tolerated therapy has revolutionized the treatment of this insidious disease. In this article, three of Bristol-Myers Squibb's HCV programs are summarized, each of which produced a clinical candidate: the NS3 protease inhibitor asunaprevir (64), marketed as Sunvepra, the NS5A replication complex inhibitor daclatasvir (117), marketed as Daklinza, and the allosteric NS5B polymerase inhibitor beclabuvir (142), which is in late stage clinical studies. A clinical study with 64 and 117 established for the first time that a chronic HCV infection could be cured by treatment with direct-acting antiviral agents alone in the absence of interferon. The development of small molecule HCV therapeutics, designed by medicinal chemists, has been hailed as "the arc of a medical triumph" but may equally well be described as "the arc of a medicinal chemistry triumph".
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Affiliation(s)
- Nicholas A Meanwell
- Department of Discovery Chemistry, Bristol-Myers Squibb Research & Development , Wallingford, Connecticut 06492, United States
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Hopkinson RJ, Tumber A, Yapp C, Chowdhury R, Aik W, Che KH, Li XS, Kristensen JBL, King ONF, Chan MC, Yeoh KK, Choi H, Walport LJ, Thinnes CC, Bush JT, Lejeune C, Rydzik AM, Rose NR, Bagg EA, McDonough MA, Krojer T, Yue WW, Ng SS, Olsen L, Brennan PE, Oppermann U, Muller-Knapp S, Klose RJ, Ratcliffe PJ, Schofield CJ, Kawamura A. 5-Carboxy-8-hydroxyquinoline is a Broad Spectrum 2-Oxoglutarate Oxygenase Inhibitor which Causes Iron Translocation. Chem Sci 2013; 4:3110-3117. [PMID: 26682036 PMCID: PMC4678600 DOI: 10.1039/c3sc51122g] [Citation(s) in RCA: 131] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
2-Oxoglutarate and iron dependent oxygenases are therapeutic targets for human diseases. Using a representative 2OG oxygenase panel, we compare the inhibitory activities of 5-carboxy-8-hydroxyquinoline (IOX1) and 4-carboxy-8-hydroxyquinoline (4C8HQ) with that of two other commonly used 2OG oxygenase inhibitors, N-oxalylglycine (NOG) and 2,4-pyridinedicarboxylic acid (2,4-PDCA). The results reveal that IOX1 has a broad spectrum of activity, as demonstrated by the inhibition of transcription factor hydroxylases, representatives of all 2OG dependent histone demethylase subfamilies, nucleic acid demethylases and γ-butyrobetaine hydroxylase. Cellular assays show that, unlike NOG and 2,4-PDCA, IOX1 is active against both cytosolic and nuclear 2OG oxygenases without ester derivatisation. Unexpectedly, crystallographic studies on these oxygenases demonstrate that IOX1, but not 4C8HQ, can cause translocation of the active site metal, revealing a rare example of protein ligand-induced metal movement.
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Affiliation(s)
- Richard J. Hopkinson
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, U.K
| | - Anthony Tumber
- Structural Genomics Consortium, University of Oxford, Headington, OX3 7DQ, U.K
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, OX3 7FZ, UK
| | - Clarence Yapp
- Structural Genomics Consortium, University of Oxford, Headington, OX3 7DQ, U.K
| | - Rasheduzzaman Chowdhury
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, U.K
| | - WeiShen Aik
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, U.K
| | - Ka Hing Che
- Structural Genomics Consortium, University of Oxford, Headington, OX3 7DQ, U.K
- Botnar Research Centre, Oxford Biomedical Research Unit, Oxford OX3 7LD, U.K
| | - Xuan Shirley Li
- Epigenetic Regulation of Chromatin Function Group, Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, U.K
| | - Jan B. L. Kristensen
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, U.K
- Department of Medicinal Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Oliver N. F. King
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, U.K
| | - Mun Chiang Chan
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, U.K
- Henry Wellcome Building for Molecular Physiology, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford OX3 7LD, U.K
| | - Kar Kheng Yeoh
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, U.K
- Henry Wellcome Building for Molecular Physiology, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford OX3 7LD, U.K
| | - Hwanho Choi
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, U.K
| | - Louise J. Walport
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, U.K
| | - Cyrille C. Thinnes
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, U.K
| | - Jacob T. Bush
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, U.K
| | - Clarisse Lejeune
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, U.K
| | - Anna M. Rydzik
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, U.K
| | - Nathan R. Rose
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, U.K
- Epigenetic Regulation of Chromatin Function Group, Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, U.K
| | - Eleanor A. Bagg
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, U.K
| | - Michael A. McDonough
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, U.K
| | - Tobias Krojer
- Structural Genomics Consortium, University of Oxford, Headington, OX3 7DQ, U.K
| | - Wyatt W. Yue
- Structural Genomics Consortium, University of Oxford, Headington, OX3 7DQ, U.K
| | - Stanley S. Ng
- Structural Genomics Consortium, University of Oxford, Headington, OX3 7DQ, U.K
| | - Lars Olsen
- Department of Medicinal Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Paul E. Brennan
- Structural Genomics Consortium, University of Oxford, Headington, OX3 7DQ, U.K
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, OX3 7FZ, UK
| | - Udo Oppermann
- Structural Genomics Consortium, University of Oxford, Headington, OX3 7DQ, U.K
- Botnar Research Centre, Oxford Biomedical Research Unit, Oxford OX3 7LD, U.K
| | | | - Robert J. Klose
- Epigenetic Regulation of Chromatin Function Group, Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, U.K
| | - Peter J. Ratcliffe
- Henry Wellcome Building for Molecular Physiology, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford OX3 7LD, U.K
| | - Christopher J. Schofield
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, U.K
| | - Akane Kawamura
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, U.K
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford, OX3 7LD, UK
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Toh EC, Dashper SG, Huq NL, Attard TJ, Cross KJ, Stanton DP, Reynolds EC. Inhibition of proteolytic activity of periodontal pathogens by casein-derived peptides. Int Dairy J 2012. [DOI: 10.1016/j.idairyj.2011.12.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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8
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Human serum albumin: from bench to bedside. Mol Aspects Med 2011; 33:209-90. [PMID: 22230555 DOI: 10.1016/j.mam.2011.12.002] [Citation(s) in RCA: 1190] [Impact Index Per Article: 91.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Accepted: 12/21/2011] [Indexed: 02/07/2023]
Abstract
Human serum albumin (HSA), the most abundant protein in plasma, is a monomeric multi-domain macromolecule, representing the main determinant of plasma oncotic pressure and the main modulator of fluid distribution between body compartments. HSA displays an extraordinary ligand binding capacity, providing a depot and carrier for many endogenous and exogenous compounds. Indeed, HSA represents the main carrier for fatty acids, affects pharmacokinetics of many drugs, provides the metabolic modification of some ligands, renders potential toxins harmless, accounts for most of the anti-oxidant capacity of human plasma, and displays (pseudo-)enzymatic properties. HSA is a valuable biomarker of many diseases, including cancer, rheumatoid arthritis, ischemia, post-menopausal obesity, severe acute graft-versus-host disease, and diseases that need monitoring of the glycemic control. Moreover, HSA is widely used clinically to treat several diseases, including hypovolemia, shock, burns, surgical blood loss, trauma, hemorrhage, cardiopulmonary bypass, acute respiratory distress syndrome, hemodialysis, acute liver failure, chronic liver disease, nutrition support, resuscitation, and hypoalbuminemia. Recently, biotechnological applications of HSA, including implantable biomaterials, surgical adhesives and sealants, biochromatography, ligand trapping, and fusion proteins, have been reported. Here, genetic, biochemical, biomedical, and biotechnological aspects of HSA are reviewed.
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Porphyromonas gingivalis cysteine proteinase inhibition by kappa-casein peptides. Antimicrob Agents Chemother 2010; 55:1155-61. [PMID: 21173178 DOI: 10.1128/aac.00466-10] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Porphyromonas gingivalis is a major pathogen associated with chronic periodontitis, an inflammatory disease of the supporting tissues of the teeth. The Arg-specific (RgpA/B) and Lys-specific (Kgp) cysteine proteinases of P. gingivalis are major virulence factors for the bacterium. In this study κ-casein(109-137) was identified in a chymosin digest of casein as an inhibiting peptide of the P. gingivalis proteinases. The peptide was synthesized and shown to inhibit proteolytic activity associated with P. gingivalis whole cells, purified RgpA-Kgp proteinase-adhesin complexes, and purified RgpB proteinase. The peptide κ-casein(109-137) exhibited synergism with Zn(II) against both Arg- and Lys-specific proteinases. The active region for inhibition was identified as κ-casein(117-137) using synthetic peptides. Kinetic studies revealed that κ-casein(109-137) inhibits in an uncompetitive manner. A molecular model based on the uncompetitive action and its synergistic ability with Zn(II) was developed to explain the mechanism of inhibition. Preincubation of P. gingivalis with κ-casein(109-137) significantly reduced lesion development in a murine model of infection.
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Smith AJT, Zhang X, Leach AG, Houk KN. Beyond picomolar affinities: quantitative aspects of noncovalent and covalent binding of drugs to proteins. J Med Chem 2009; 52:225-33. [PMID: 19053779 DOI: 10.1021/jm800498e] [Citation(s) in RCA: 136] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Adam J T Smith
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, USA
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11
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Abstract
Tryptases and chymases are the major proteins stored and secreted by mast cells. The types, amounts, and properties of these serine peptidases vary by mast cell subtype, tissue, and mammal of origin. Membrane-anchored gamma-tryptases are tryptic, prostasin-like, type I peptidases that remain membrane attached on release and act locally. Soluble tryptases, including their close relatives, mastins, form inhibitor-resistant oligomers that act more remotely. Befitting their greater destructive potential, chymases are quickly inhibited after release, although some gain protection by associating with proteoglycans. Most chymase-like enzymes, including mast cell cathepsin G, hydrolyze chymotryptic substrates, an uncommon capability in the proteome. Some rodent chymases, however, have mutations resulting in elastolytic activity. Secreted tryptases and chymases promote inflammation, matrix destruction, and tissue remodeling by several mechanisms, including destroying procoagulant, matrix, growth, and differentiation factors and activating proteinase-activated receptors, urokinase, metalloproteinases, and angiotensin. They also modulate immune responses by hydrolyzing chemokines and cytokines. At least one chymase protects mice from intestinal worms. Tryptases and chymases can also oppose inflammation by inactivating allergens and neuropeptides causing inflammation and bronchoconstriction. Thus, like mast cells themselves, mast cell serine peptidases play multiple roles in host defense, and any accounting of benefit versus harm is necessarily context specific.
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Affiliation(s)
- George H Caughey
- Cardiovascular Research Institute, University of California at San Francisco, San Francisco, CA, USA.
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Cronan CA, Potempa J, Travis J, Mayo JA. Inhibition of Porphyromonas gingivalis proteinases (gingipains) by chlorhexidine: synergistic effect of Zn(II). ACTA ACUST UNITED AC 2006; 21:212-7. [PMID: 16842504 DOI: 10.1111/j.1399-302x.2006.00277.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
BACKGROUND/AIMS Gingipains, proteolytic enzymes produced by the periodontal pathogen Porphyromonas gingivalis, are regarded as virulence factors in the pathogenesis of periodontitis. Inhibition of gingipain activity therefore may have therapeutic potential, and it has been suggested that chlorhexidine may inhibit the activities of these enzymes. The purposes of the present study were to examine systematically the inhibitory effects of chlorhexidine on three purified gingipains and to determine the effect of Zn(II) on chlorhexidine inhibition. METHODS The activities of lys-gingipain (Kgp) and two forms of arg-gingipain (RgpB and HRgpA) were measured in the presence of varying concentrations of chlorhexidine and with chlorhexidine supplemented with Zn(II). Inhibition constants (K(i)'s) were determined for chlorhexidine alone and in the presence of Zn(II). Fractional inhibitory constant indices were calculated to assess the synergy of the chlorhexidine-Zn(II) inhibition. RESULTS RgpB, HRgpA, and Kgp were all inhibited by chlorhexidine with K(i)'s in the micromolar range. For RgpB and HRgpA, the inhibitory effects of chlorhexidine were enhanced 3-30-fold by Zn(II). The chlorhexidine-Zn(II) interaction was synergistic for inhibition of HRgpA and RgpB. For Kgp, the effect of Zn(II) on chlorhexidine inhibition was antagonistic. CONCLUSIONS Chlorhexidine is an effective inhibitor of gingipains, and the inhibition of R-gingipains is enhanced by Zn(II). A mixture of chlorhexidine and Zn(II) may be useful as an adjunct in the treatment of periodontitis and in the post-treatment maintenance of periodontitis patients.
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Affiliation(s)
- C A Cronan
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602-7229, USA
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13
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Yu W, Dener JM, Dickman DA, Grothaus P, Ling Y, Liu L, Havel C, Malesky K, Mahajan T, O'Brian C, Shelton EJ, Sperandio D, Tong Z, Yee R, Mordenti JJ. Identification of metabolites of the tryptase inhibitor CRA-9249: Observation of a metabolite derived from an unexpected hydroxylation pathway. Bioorg Med Chem Lett 2006; 16:4053-8. [PMID: 16713261 DOI: 10.1016/j.bmcl.2006.05.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2006] [Revised: 04/28/2006] [Accepted: 05/01/2006] [Indexed: 11/23/2022]
Abstract
The metabolites of the tryptase inhibitor CRA-9249 were identified after exposure to liver microsomes. CRA-9249 was found to be degraded rapidly in liver microsomes from rabbit, dog, cynomolgus monkey, and human, and less rapidly in microsomes from rat. The key metabolites included cleavage of an aryl ether, in addition to an unexpected hydroxylation of the amide side chain adjacent to the amide nitrogen. The chemical structures of both metabolites were confirmed by synthesis and comparison to material isolated from the liver microsomes. Several suspected hydroxylated metabolites were also synthesized and analyzed as part of the structure identification process.
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Affiliation(s)
- Walter Yu
- Department of Drug Metabolism and Pharmacokinetics, Celera Genomics, 180 Kimball Way, South San Francisco, CA 94080, USA
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Dener JM, O’Bryan C, Yee R, Shelton EJ, Sperandio D, Mahajan T, Palmer JT, Spencer JR, Tong Z. Development of a scalable synthesis of a nonbasic inhibitor of the serine protease tryptase. Tetrahedron Lett 2006. [DOI: 10.1016/j.tetlet.2006.04.149] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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15
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Young WB, Sprengeler P, Shrader WD, Li Y, Rai R, Verner E, Jenkins T, Fatheree P, Kolesnikov A, Janc JW, Cregar L, Elrod K, Katz B. Generation of potent coagulation protease inhibitors utilizing zinc-mediated chelation. Bioorg Med Chem Lett 2006; 16:710-3. [PMID: 16257204 DOI: 10.1016/j.bmcl.2005.10.023] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2005] [Revised: 09/30/2005] [Accepted: 10/06/2005] [Indexed: 11/23/2022]
Abstract
Inhibition of coagulation proteases such as thrombin, fXa, and fVIIa has been a focus of ongoing research to produce safe and effective antithrombotic agents. Herein, we describe a unique zinc-mediated chelation strategy to streamline the discovery of potent inhibitors of fIIa, fXa, and fVIIa. SAR studies that led to the development of selective inhibitors of fXa will also be detailed.
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Affiliation(s)
- Wendy B Young
- Celera, 180 Kimball Way, South San Francisco, CA 94080, USA.
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16
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Ilies MA, Supuran CT, Scozzafava A. Therapeutic applications of serine protease inhibitors. Expert Opin Ther Pat 2005. [DOI: 10.1517/13543776.12.8.1181] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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17
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Cairns JA. Inhibitors of mast cell tryptase beta as therapeutics for the treatment of asthma and inflammatory disorders. Pulm Pharmacol Ther 2004; 18:55-66. [PMID: 15607128 DOI: 10.1016/j.pupt.2004.09.032] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2004] [Revised: 09/14/2004] [Accepted: 09/22/2004] [Indexed: 11/20/2022]
Abstract
A survey of the available biological data on tryptase inhibitors suggests that there is considerable interest in tryptase as a therapeutic target particularly for the treatment of allergic asthma and inflammatory disorders. This interest was driven primarily by data from studies carried out on the cellular and in vivo actions of this serine protease over the past decade, all of which have suggested a pro-inflammatory role for tryptase. Tryptase beta is the form of interest in allergic asthma and the data from numerous studies have shown that tryptase cannot only contribute to airway bronchoconstriction and hyperresponsiveness, but may have a key role in fibrosis and ECM turnover, hallmarks of the remodeling process. Hence, inhibitors of tryptase have the potential to make an impact on fibrosis and airway wall remodelling. However, few studies, if any, have been carried out to determine the effect of tryptase inhibitors on airway remodeling and this is an area that warrants further investigation with the appropriate models because the eventual positioning of tryptase inhibitors in asthma therapy will be strengthened by data supporting an impact on airway remodeling in addition to effects on bronchial hyperresponsiveness. This review has focused on tryptase inhibitors in the pipeline and it is clear that with a few exceptions, the majority of these compounds are targeted for inhaled delivery. Finally, judging by the interest from numerous pharmaceutical companies, it appears the stage is set for tryptase inhibitors to make their mark as drugs of the future for allergic asthma and the results from clinical trials is awaited with eager anticipation.
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Affiliation(s)
- J A Cairns
- Respiratory and Rheumatoid Arthritis Disease Group, Aventis Pharmaceuticals, Bridgewater, NJ 08807, USA.
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18
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Katz BA, Luong C, Ho JD, Somoza JR, Gjerstad E, Tang J, Williams SR, Verner E, Mackman RL, Young WB, Sprengeler PA, Chan H, Mortara K, Janc JW, McGrath ME. Dissecting and Designing Inhibitor Selectivity Determinants at the S1 Site Using an Artificial Ala190 Protease (Ala190 uPA). J Mol Biol 2004; 344:527-47. [PMID: 15522303 DOI: 10.1016/j.jmb.2004.09.032] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2004] [Revised: 09/14/2004] [Accepted: 09/15/2004] [Indexed: 11/21/2022]
Abstract
A site-directed mutant of the serine protease urokinase-type plasminogen activator (uPA), was produced to assess the contribution of the Ser190 side-chain to the affinity and selectivity of lead uPA inhibitors in the absence of other differences present in comparisons of natural proteases. Crystallography and enzymology involving WT and Ala190 uPA were used to calculate free energy binding contributions of hydrogen bonds involving the Ser190 hydroxyl group (O(gamma)(Ser190)) responsible for the remarkable selectivity of 6-halo-5-amidinoindole and 6-halo-5-amidinobenzimidazole inhibitors toward uPA and against natural Ala190 protease anti-targets. Crystal structures of uPA complexes of novel, active site-directed arylguanidine and 2-aminobenzimidazole inhibitors of WT uPA, together with associated K(i) values for WT and Ala190 uPA, also indicate a significant role of Ser190 in the binding of these classes of uPA inhibitors. Structures and associated K(i) values for a lead inhibitor (CA-11) bound to uPA and to five other proteases, as well as for other leads bound to multiple proteases, help reveal the features responsible for the potency (K(i)=11nM) and selectivity of the remarkably small inhibitor, CA-11. The 6-fluoro-5-amidinobenzimidzole, CA-11, is more than 1000-fold selective against natural Ala190 protease anti-targets, and more than 100-fold selective against other Ser190 anti-targets.
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Affiliation(s)
- Bradley A Katz
- Celera, 180 Kimball Way, South San Francisco, CA 94080, USA.
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19
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Stewart AJ, Blindauer CA, Berezenko S, Sleep D, Sadler PJ. Interdomain zinc site on human albumin. Proc Natl Acad Sci U S A 2003; 100:3701-6. [PMID: 12598656 PMCID: PMC152985 DOI: 10.1073/pnas.0436576100] [Citation(s) in RCA: 149] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Albumin is the major transport protein in blood for Zn(2+), a metal ion required for physiological processes and recruited by various drugs and toxins. However, the Zn(2+)-binding site(s) on albumin is ill-defined. We have analyzed the 18 x-ray crystal structures of human albumin in the PDB and identified a potential five-coordinate Zn site at the interface of domains I and II consisting of N ligands from His-67 and His-247 and O ligands from Asn-99, Asp-249, and H(2)O, which are the same amino acid ligands as those in the zinc enzymes calcineurin, endonucleotidase, and purple acid phosphatase. The site is preformed in unliganded apo-albumin and highly conserved in mammalian albumins. We have used (111)Cd NMR as a probe for Zn(2+) binding to recombinant human albumin. We show that His-67 --> Ala (His67Ala) mutation strongly perturbs Cd(2+) binding, whereas the mutations Cys34Ala, or His39Leu and Tyr84Phe (residues which may H-bond to Cys-34) have no effect. Weak Cl(-) binding to the fifth coordination site of Cd(2+) was demonstrated. Cd(2+) binding was dramatically affected by high fatty acid loading of albumin. Analysis of the x-ray structures suggests that fatty acid binding to site 2 triggers a spring-lock mechanism, which disengages the upper (His-67Asn-99) and lower (His-247Asp-249) halves of the metal site. These findings provide a possible mechanism whereby fatty acids (and perhaps other small molecules) could influence the transport and delivery of zinc in blood.
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Affiliation(s)
- Alan J Stewart
- School of Chemistry, University of Edinburgh, West Mains Road, Edinburgh EH9 3JJ, United Kingdom
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20
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Higgin JJ, Yakovlev GI, Mitkevich VA, Makarov AA, Raines RT. Zinc(II)-mediated inhibition of a ribonuclease by an N-hydroxyurea nucleotide. Bioorg Med Chem Lett 2003; 13:409-12. [PMID: 12565940 DOI: 10.1016/s0960-894x(02)00929-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The inhibition of ribonuclease Bi by 3'-N-hydroxyurea-3'-deoxythymidine 5'-phosphate is enhanced by 30-fold in the presence of Zn(2+). Thus, an N-hydroxyurea nucleotide can recruit Zn(2+) to inhibit the enzymatic activity of a ribonuclease. This result engenders a general strategy for the inhibition of non-metalloenzymes by metal complexes.
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Affiliation(s)
- Joshua J Higgin
- Department of Chemistry, University of Wisconsin-Madison, Madfison, WI 53706, USA
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21
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Krauser JA, Potempa J, Travis J, Powers JC. Inhibition of arginine gingipains (RgpB and HRgpA) with benzamidine inhibitors: zinc increases inhibitory potency. Biol Chem 2002; 383:1193-8. [PMID: 12437105 DOI: 10.1515/bc.2002.131] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
We assayed several benzamidine derivatives for inhibition potency with HRgpA and RgpB gingipains, enzymes which are involved in the pathogenesis of gingivitis and periodontal disease. The benzamidine derivatives proved to be effective inhibitors of HRgpA and RgpB, with the best inhibitor being a bis-benzamidine with a urea linker (Ki=30 microM). The inhibition potency was increased 2-3 fold in the presence of low concentrations of zinc with the benzamidines containing a urea moiety linking the two aromatic rings. We propose an inhibition model involving a tetrahedral zinc atom coordinated with the active site Cys and His of gingipain and the urea linker in the benzamidine inhibitor. In summary, we have discovered a new series of effective inhibitors for the gingipains and found a novel way to increase inhibitor potency with the HRgpA and RgpB gingipains using zinc.
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Affiliation(s)
- Joel A Krauser
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta 30093-0400, USA
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22
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Lebon F, Boggetto N, Ledecq M, Durant F, Benatallah Z, Sicsic S, Lapouyade R, Kahn O, Mouithys-Mickalad A, Deby-Dupont G, Reboud-Ravaux M. Metal-organic compounds: a new approach for drug discovery. N1-(4-methyl-2-pyridyl)-2,3,6-trimethoxybenzamide copper(II) complex as an inhibitor of human immunodeficiency virus 1 protease. Biochem Pharmacol 2002; 63:1863-73. [PMID: 12034371 DOI: 10.1016/s0006-2952(02)00918-8] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The use of metal-organic complexes is a potentially fruitful approach for the development of novel enzyme inhibitors. They hold the attractive promise of forming stronger attachments with the target by combining the co-ordination ability of metals with the unique stereoelectronic properties of the ligand. We demonstrated that this approach can be successfully used to inhibit the protease of the human immunodeficiency virus (type 1). Several ligands bearing substituents designed to interact with the catalytic site of the enzyme when complexed to Cu(2+) were synthesised. The inhibition pattern of the resulting copper(II) complexes was analysed. We showed that the copper(II) complex of N1-(4-methyl-2-pyridyl)-2,3,6-trimethoxybenzamide (C1) interacts with the active site of the enzyme leading to competitive inhibition. On the other hand, N2-pyridine-amide ligands and oxazinane carboxamide ligand were found to be poor chelators of the cupric ion under the enzymatic assay conditions. In these cases, the observed inhibition was attributed to released cupric ions which react with cysteine residues on the surface of the protease. While unchelated metal cations are not likely to be useful agents, metal chelates such as C1 should be considered as promising lead compounds for the development of targeted drugs.
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Affiliation(s)
- Florence Lebon
- Facultés Universitaires Notre-Dame de la Paix, Laboratoire de Chimie Moléculaire Structurale, 61 rue de Bruxelles, 5000 Namur, Belgium
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Katz BA, Sprengeler PA, Luong C, Verner E, Elrod K, Kirtley M, Janc J, Spencer JR, Breitenbucher JG, Hui H, McGee D, Allen D, Martelli A, Mackman RL. Engineering inhibitors highly selective for the S1 sites of Ser190 trypsin-like serine protease drug targets. CHEMISTRY & BIOLOGY 2001; 8:1107-21. [PMID: 11731301 DOI: 10.1016/s1074-5521(01)00084-9] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
BACKGROUND Involved or implicated in a wide spectrum of diseases, trypsin-like serine proteases comprise well studied drug targets and anti-targets that can be subdivided into two major classes. In one class there is a serine at position 190 at the S1 site, as in urokinase type plasminogen activator (urokinase or uPA) and factor VIIa, and in the other there is an alanine at 190, as in tissue type plasminogen activator (tPA) and factor Xa. A hydrogen bond unique to Ser190 protease-arylamidine complexes between O gamma(Ser190) and the inhibitor amidine confers an intrinsic preference for such inhibitors toward Ser190 proteases over Ala190 counterparts. RESULTS Based on the structural differences between the S1 sites of Ser190 and Ala190 protease-arylamidine complexes, we amplified the selectivity of amidine inhibitors toward uPA and against tPA, by factors as high as 220-fold, by incorporating a halo group ortho to the amidine of a lead inhibitor scaffold. Comparison of K(i) values of such halo-substituted and parent inhibitors toward a panel of Ser190 and Ala190 proteases demonstrates pronounced selectivity of the halo analogs for Ser190 proteases over Ala190 counterparts. Crystal structures of Ser190 proteases, uPA and trypsin, and of an Ala190 counterpart, thrombin, bound by a set of ortho (halo, amidino) aryl inhibitors and of non-halo parents reveal the structural basis of the exquisite selectivity and validate the design principle. CONCLUSIONS Remarkable selectivity enhancements of exceptionally small inhibitors are achieved toward the uPA target over the highly similar tPA anti-target through a single atom substitution on an otherwise relatively non-selective scaffold. Overall selectivities for uPA over tPA as high as 980-fold at physiological pH were realized. The increase in selectivity results from the displacement of a single bound water molecule common to the S1 site of both the uPA target and the tPA anti-target because of the ensuing deficit in hydrogen bonding of the arylamidine inhibitor when bound in the Ala190 protease anti-target.
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Affiliation(s)
- B A Katz
- Axys Pharmaceutical Corporation, 385 Oyster Point Boulevard, South San Francisco, CA 94080, USA.
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24
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Valente S, Gobbo M, Licini G, Scarso A, Scrimin P. Allosteric Regulation of an HIV-1 Protease Inhibitor by ZnII Ions. Angew Chem Int Ed Engl 2001; 40:3899-3902. [DOI: 10.1002/1521-3773(20011015)40:20<3899::aid-anie3899>3.0.co;2-c] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2001] [Indexed: 12/15/2022]
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26
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Katz BA, Elrod K, Luong C, Rice MJ, Mackman RL, Sprengeler PA, Spencer J, Hataye J, Janc J, Link J, Litvak J, Rai R, Rice K, Sideris S, Verner E, Young W. A novel serine protease inhibition motif involving a multi-centered short hydrogen bonding network at the active site. J Mol Biol 2001; 307:1451-86. [PMID: 11292354 DOI: 10.1006/jmbi.2001.4516] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We describe a new serine protease inhibition motif in which binding is mediated by a cluster of very short hydrogen bonds (<2.3 A) at the active site. This protease-inhibitor binding paradigm is observed at high resolution in a large set of crystal structures of trypsin, thrombin, and urokinase-type plasminogen activator (uPA) bound with a series of small molecule inhibitors (2-(2-phenol)indoles and 2-(2-phenol)benzimidazoles). In each complex there are eight enzyme-inhibitor or enzyme-water-inhibitor hydrogen bonds at the active site, three of which are very short. These short hydrogen bonds connect a triangle of oxygen atoms comprising O(gamma)(Ser195), a water molecule co-bound in the oxyanion hole (H(2)O(oxy)), and the phenolate oxygen atom of the inhibitor (O6'). Two of the other hydrogen bonds between the inhibitor and active site of the trypsin and uPA complexes become short in the thrombin counterparts, extending the three-centered short hydrogen-bonding array into a tetrahedral array of atoms (three oxygen and one nitrogen) involved in short hydrogen bonds. In the uPA complexes, the extensive hydrogen-bonding interactions at the active site prevent the inhibitor S1 amidine from forming direct hydrogen bonds with Asp189 because the S1 site is deeper in uPA than in trypsin or thrombin. Ionization equilibria at the active site associated with inhibitor binding are probed through determination and comparison of structures over a wide range of pH (3.5 to 11.4) of thrombin complexes and of trypsin complexes in three different crystal forms. The high-pH trypsin-inhibitor structures suggest that His57 is protonated at pH values as high as 9.5. The pH-dependent inhibition of trypsin, thrombin, uPA and factor Xa by 2-(2-phenol)benzimidazole analogs in which the pK(a) of the phenol group is modulated is shown to be consistent with a binding process involving ionization of both the inhibitor and the enzyme. These data further suggest that the pK(a) of His57 of each protease in the unbound state in solution is about the same, approximately 6.8. By comparing inhibition constants (K(i) values), inhibitor solubilities, inhibitor conformational energies and corresponding structures of short and normal hydrogen bond-mediated complexes, we have estimated the contribution of the short hydrogen bond networks to inhibitor affinity ( approximately 1.7 kcal/mol). The structures and K(i) values associated with the short hydrogen-bonding motif are compared with those corresponding to an alternate, Zn(2+)-mediated inhibition motif at the active site. Structural differences among apo-enzymes, enzyme-inhibitor and enzyme-inhibitor-Zn(2+) complexes are discussed in the context of affinity determinants, selectivity development, and structure-based inhibitor design.
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Affiliation(s)
- B A Katz
- Axys Pharmaceuticals Corporation, 385 Oyster Point Boulevard, Suite 3, South San Francisco, CA, 94080, USA.
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