1
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Kim HR, Tagirasa R, Yoo E. Covalent Small Molecule Immunomodulators Targeting the Protease Active Site. J Med Chem 2021; 64:5291-5322. [PMID: 33904753 DOI: 10.1021/acs.jmedchem.1c00172] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Cells of the immune system utilize multiple proteases to regulate cell functions and orchestrate innate and adaptive immune responses. Dysregulated protease activities are implicated in many immune-related disorders; thus, protease inhibitors have been actively investigated for pharmaceutical development. Although historically considered challenging with concerns about toxicity, compounds that covalently modify the protease active site represent an important class of agents, emerging not only as chemical probes but also as approved drugs. Here, we provide an overview of technologies useful for the study of proteases with the focus on recent advances in chemoproteomic methods and screening platforms. By highlighting covalent inhibitors that have been designed to target immunomodulatory proteases, we identify opportunities for the development of small molecule immunomodulators.
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Affiliation(s)
- Hong-Rae Kim
- Chemical Biology Laboratory, National Cancer Institute, Frederick, Maryland 21702, United States
| | - Ravichandra Tagirasa
- Chemical Biology Laboratory, National Cancer Institute, Frederick, Maryland 21702, United States
| | - Euna Yoo
- Chemical Biology Laboratory, National Cancer Institute, Frederick, Maryland 21702, United States
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2
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Sveistyte A, Gibbins T, Tyrrell KJ, Miller CJ, Foley MH, Plymale AE, Wright AT, Brandvold KR. Simple Analysis of Primary and Secondary Bile Salt Hydrolysis in Mouse and Human Gut Microbiome Samples by Using Fluorogenic Substrates. Chembiochem 2020; 21:3539-3543. [PMID: 32761683 DOI: 10.1002/cbic.202000370] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 08/03/2020] [Indexed: 12/13/2022]
Abstract
Animals produce bile to act as an antibacterial agent and to maximize the absorption of lipophilic nutrients in the gut. The physical properties of bile are largely dictated by amphipathic bile salt molecules, which also participate in signaling pathways by modulating physiological processes upon binding host receptors. Upon excretion of bile salts from the gall bladder into the intestine, the gut microbiota can create metabolites with modified signaling capabilities. The category and magnitude of bile salt metabolism can have positive or negative effects on the host. A key modification is bile salt hydrolysis, which is a prerequisite for all additional microbial transformations. We have synthesized five different fluorogenic bile salts for simple and continuous reporting of hydrolysis in both murine and human fecal samples. Our data demonstrate that most gut microbiomes have the highest capacity for hydrolysis of host-produced primary bile salts, but some microbially modified secondary bile salts also display significant turnover.
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Affiliation(s)
- Agne Sveistyte
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Teresa Gibbins
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Kimberly J Tyrrell
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Carson J Miller
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Matt H Foley
- NC State Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA
| | - Andrew E Plymale
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Aaron T Wright
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA.,The Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, WA 99163, USA
| | - Kristoffer R Brandvold
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA.,Elson S. Floyd College of Medicine, Washington State University, Spokane, WA 99202, USA
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3
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Yoo E, Stokes BH, de Jong H, Vanaerschot M, Kumar TRS, Lawrence N, Njoroge M, Garcia A, Van der Westhuyzen R, Momper JD, Ng CL, Fidock DA, Bogyo M. Defining the Determinants of Specificity of Plasmodium Proteasome Inhibitors. J Am Chem Soc 2018; 140:11424-11437. [PMID: 30107725 PMCID: PMC6407133 DOI: 10.1021/jacs.8b06656] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The Plasmodium proteasome is an emerging antimalarial target due to its essential role in all the major life cycle stages of the parasite and its contribution to the establishment of resistance to artemisinin (ART)-based therapies. However, because of a similarly essential role for the host proteasome, the key property of any antiproteasome therapeutic is selectivity. Several parasite-specific proteasome inhibitors have recently been reported, however, their selectivity must be improved to enable clinical development. Here we describe screening of diverse libraries of non-natural synthetic fluorogenic substrates to identify determinants at multiple positions on the substrate that produce enhanced selectivity. We find that selection of an optimal electrophilic "warhead" is essential to enable high selectivity that is driven by the peptide binding elements on the inhibitor. We also find that host cell toxicity is dictated by the extent of coinhibition of the human β2 and β5 subunits. Using this information, we identify compounds with over 3 orders of magnitude selectivity for the parasite enzyme. Optimization of the pharmacological properties resulted in molecules that retained high potency and selectivity, were soluble, sufficiently metabolically stable and orally bioavailable. These molecules are highly synergistic with ART and can clear parasites in a mouse model of infection, making them promising leads as antimalarial drugs.
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Affiliation(s)
- Euna Yoo
- Department of Pathology and Stanford University
School of Medicine, Stanford, California 94305, United States
| | - Barbara H. Stokes
- Department of Microbiology and Immunology Columbia
University Medical Center, New York 10032, United States
| | - Hanna de Jong
- Department of Pathology and Stanford University
School of Medicine, Stanford, California 94305, United States
| | - Manu Vanaerschot
- Department of Microbiology and Immunology Columbia
University Medical Center, New York 10032, United States
| | - TRS Kumar
- Department of Microbiology and Immunology Columbia
University Medical Center, New York 10032, United States
| | - Nina Lawrence
- Drug Discovery and Development Centre (H3D),
University of Cape Town, Rondebosch 7701, South Africa
| | - Mathew Njoroge
- Drug Discovery and Development Centre (H3D),
University of Cape Town, Rondebosch 7701, South Africa
| | - Arnold Garcia
- Skaggs School of Pharmacy and Pharmaceutical Sciences,
University of California, San Diego, La Jolla, California 92093, United States
| | | | - Jeremiah D. Momper
- Skaggs School of Pharmacy and Pharmaceutical Sciences,
University of California, San Diego, La Jolla, California 92093, United States
| | - Caroline L. Ng
- Department of Microbiology and Immunology Columbia
University Medical Center, New York 10032, United States
- Department of Pathology and Microbiology, University
of Nebraska Medical Center, Omaha, Nebraska 68198, United States
| | - David A. Fidock
- Department of Microbiology and Immunology Columbia
University Medical Center, New York 10032, United States
- Division of Infectious Diseases, Department of
Medicine, Columbia University Medical Center, New York 10032, United States
| | - Matthew Bogyo
- Department of Pathology and Stanford University
School of Medicine, Stanford, California 94305, United States
- Department of Microbiology and Immunology, Stanford
University School of Medicine, Stanford, California 94305, United States
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4
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White A, Koelper A, Russell A, Larsen EM, Kim C, Lavis LD, Hoops GC, Johnson RJ. Fluorogenic structure activity library pinpoints molecular variations in substrate specificity of structurally homologous esterases. J Biol Chem 2018; 293:13851-13862. [PMID: 30006352 DOI: 10.1074/jbc.ra118.003972] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 07/11/2018] [Indexed: 01/08/2023] Open
Abstract
Cellular esterases catalyze many essential biological functions by performing hydrolysis reactions on diverse substrates. The promiscuity of esterases complicates assignment of their substrate preferences and biological functions. To identify universal factors controlling esterase substrate recognition, we designed a 32-member structure-activity relationship (SAR) library of fluorogenic ester substrates and used this library to systematically interrogate esterase preference for chain length, branching patterns, and polarity to differentiate common classes of esterase substrates. Two structurally homologous bacterial esterases were screened against this library, refining their previously broad overlapping substrate specificity. Vibrio cholerae esterase ybfF displayed a preference for γ-position thioethers and ethers, whereas Rv0045c from Mycobacterium tuberculosis displayed a preference for branched substrates with and without thioethers. We determined that this substrate differentiation was partially controlled by individual substrate selectivity residues Tyr-119 in ybfF and His-187 in Rv0045c; reciprocal substitution of these residues shifted each esterase's substrate preference. This work demonstrates that the selectivity of esterases is tuned based on transition state stabilization, identifies thioethers as an underutilized functional group for esterase substrates, and provides a rapid method for differentiating structural isozymes. This SAR library could have multifaceted future applications, including in vivo imaging, biocatalyst screening, molecular fingerprinting, and inhibitor design.
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Affiliation(s)
- Alex White
- From the Department of Chemistry and Biochemistry, Butler University, Indianapolis, Indiana 46208-3443 and
| | - Andrew Koelper
- From the Department of Chemistry and Biochemistry, Butler University, Indianapolis, Indiana 46208-3443 and
| | - Arielle Russell
- From the Department of Chemistry and Biochemistry, Butler University, Indianapolis, Indiana 46208-3443 and
| | - Erik M Larsen
- From the Department of Chemistry and Biochemistry, Butler University, Indianapolis, Indiana 46208-3443 and
| | - Charles Kim
- the Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia 20147-2439
| | - Luke D Lavis
- the Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia 20147-2439
| | - Geoffrey C Hoops
- From the Department of Chemistry and Biochemistry, Butler University, Indianapolis, Indiana 46208-3443 and
| | - R Jeremy Johnson
- From the Department of Chemistry and Biochemistry, Butler University, Indianapolis, Indiana 46208-3443 and
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5
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Synthesis of a HyCoSuL peptide substrate library to dissect protease substrate specificity. Nat Protoc 2017; 12:2189-2214. [PMID: 28933778 DOI: 10.1038/nprot.2017.091] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Many biologically and chemically based approaches have been developed to design highly active and selective protease substrates and probes. It is, however, difficult to find substrate sequences that are truly selective for any given protease, as different proteases can demonstrate a great deal of overlap in substrate specificities. In some cases, better enzyme selectivity can be achieved using peptide libraries containing unnatural amino acids such as the hybrid combinatorial substrate library (HyCoSuL), which uses both natural and unnatural amino acids. HyCoSuL is a combinatorial library of tetrapeptides containing amino acid mixtures at the P4-P2 positions, a fixed amino acid at the P1 position, and an ACC (7-amino-4-carbamoylmethylcoumarin) fluorescent tag occupying the P1' position. Once the peptide is recognized and cleaved by a protease, the ACC is released and produces a readable fluorescence signal. Here, we describe the synthesis and screening of HyCoSuL for human caspases and legumain. We also discuss possible modifications and adaptations of this approach that make it a useful tool for developing highly active and selective reagents for a wide variety of proteolytic enzymes. The protocol can be divided into three major parts: (i) solid-phase synthesis of the fluorescence-labeled HyCoSuL, (ii) screening of protease P4-P2 preferences, and (iii) synthesis of the optimized activity probes equipped with an AOMK (acyloxymethyl ketone) reactive group and a biotin label for easy detection. Beginning with the library design, the entire protocol can be completed in 4-8 weeks (HyCoSuL synthesis: 3-5 weeks; HyCoSuL screening per enzyme: 4-8 d; and activity-based probe synthesis: 1-2 weeks).
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6
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Qin G, Ma J, Chen X, Chu Z, She YM. Methylated-antibody affinity purification to improve proteomic identification of plant RNA polymerase Pol V complex and the interacting proteins. Sci Rep 2017; 7:42943. [PMID: 28224978 PMCID: PMC5320500 DOI: 10.1038/srep42943] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 01/17/2017] [Indexed: 11/09/2022] Open
Abstract
Affinity purification followed by enzymatic digestion and mass spectrometry has been widely utilized for the sensitive detection of interacting proteins and protein complexes in various organisms. In plants, the method is technically challenging due to the low abundance proteins, non-specific binding and difficulties of eluting interacting proteins from antibody beads. In this report, we describe a strategy to modify antibodies by reductive methylation of lysines without affecting their binding properties, followed by on-bead digestion of bound proteins with endoproteinase Lys-C. By this method, the antibody remains intact and does not interfere with the downstream identification of interacting proteins. Non-specific binding proteins were excluded using 14N/15N-metabolic labeling of wild-type and the transgenic plant counterparts. The method was employed to identify 12 co-immunoprecipitated protein subunits in Pol V complex and to discover 17 potential interacting protein targets in Arabidopsis. Our results demonstrated that the modification of antibodies by reductive dimethylation can improve the reliability and sensitivity of identifying low-abundance proteins through on-bead digestion and mass spectrometry. We also show that coupling this technique with chemical crosslinking enables in-depth characterization of endogenous protein complexes and the protein-protein interaction networks including mapping the surface topology and post-translational modifications of interacting proteins.
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Affiliation(s)
- Guochen Qin
- Shanghai Center for Plant Stress Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 3888 Chenhua Road, Shanghai 201602, P. R. China
| | - Jun Ma
- Shanghai Center for Plant Stress Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 3888 Chenhua Road, Shanghai 201602, P. R. China
| | - Xiaomei Chen
- Shanghai Center for Plant Stress Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 3888 Chenhua Road, Shanghai 201602, P. R. China
| | - Zhaoqing Chu
- Shanghai Chenshan Plant Science Research Center and Shanghai Chenshan Botanic Garden, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 3888 Chenhua Road, Shanghai 201602, P. R. China
| | - Yi-Min She
- Shanghai Center for Plant Stress Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 3888 Chenhua Road, Shanghai 201602, P. R. China.,Centre for Biologics Evaluation, Biologics and Genetic Therapies Directorate, Health Canada, Ottawa, Ontario, K1A 0K9, Canada
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7
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Kasperkiewicz P, Poreba M, Groborz K, Drag M. Emerging challenges in the design of selective substrates, inhibitors and activity-based probes for indistinguishable proteases. FEBS J 2017; 284:1518-1539. [PMID: 28052575 PMCID: PMC7164106 DOI: 10.1111/febs.14001] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2016] [Revised: 12/02/2016] [Accepted: 01/03/2017] [Indexed: 12/31/2022]
Abstract
Proteases are enzymes that hydrolyze the peptide bond of peptide substrates and proteins. Despite significant progress in recent years, one of the greatest challenges in the design and testing of substrates, inhibitors and activity‐based probes for proteolytic enzymes is achieving specificity toward only one enzyme. This specificity is particularly important if the enzyme is present with other enzymes with a similar catalytic mechanism and substrate specificity but completely different functionality. The cross‐reactivity of substrates, inhibitors and activity‐based probes with other enzymes can significantly impair or even prevent investigations of a target protease. In this review, we describe important concepts and the latest challenges, focusing mainly on peptide‐based substrate specificity techniques used to distinguish individual enzymes within major protease families.
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Affiliation(s)
- Paulina Kasperkiewicz
- Department of Bioorganic Chemistry, Faculty of Chemistry, Wroclaw University of Science and Technology, Poland
| | - Marcin Poreba
- Department of Bioorganic Chemistry, Faculty of Chemistry, Wroclaw University of Science and Technology, Poland
| | - Katarzyna Groborz
- Department of Bioorganic Chemistry, Faculty of Chemistry, Wroclaw University of Science and Technology, Poland
| | - Marcin Drag
- Department of Bioorganic Chemistry, Faculty of Chemistry, Wroclaw University of Science and Technology, Poland
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8
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Deng Z, Mao J, Wang Y, Zou H, Ye M. Enzyme Kinetics for Complex System Enables Accurate Determination of Specificity Constants of Numerous Substrates in a Mixture by Proteomics Platform. Mol Cell Proteomics 2017; 16:135-145. [PMID: 27852747 PMCID: PMC5217779 DOI: 10.1074/mcp.m116.062869] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 10/20/2016] [Indexed: 01/05/2023] Open
Abstract
Many important experiments in proteomics including protein digestion, enzyme substrate screening, enzymatic labeling, etc., involve the enzymatic reactions in a complex system where numerous substrates coexists with an enzyme. However, the enzyme kinetics in such a system remains unexplored and poorly understood. Herein, we derived and validated the kinetics equations for the enzymatic reactions in complex system. We developed an iteration approach to depict the enzymatic reactions in complex system. It was validated by 630 time-course points from 24 enzymatic reaction experiments and was demonstrated to be a powerful tool to simulate the reactions in the complex system. By applying this approach, we found that the ratio of substrate depletion is independent of other coexisted substrates under specific condition. This observation was then validated by experiments. Based on this striking observation, a simplified model was developed to determine the catalytic efficiencies of numerous competing substrates presented in the complex enzyme reaction system. When coupled with high-throughput quantitative proteomics technique, this simplified model enabled the accurate determination of catalytic efficiencies for 2369 peptide substrates of a protease by using only one enzymatic reaction experiment. Thus, this study provided, in the first time, a validated model for the large scale determination of specificity constants which could enable the enzyme substrate screening approach turned from a qualitative method of identifying substrates to a quantitative method of identifying and prioritizing substrates. Data are available via ProteomeXchange with identifier PXD004665.
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Affiliation(s)
- Zhenzhen Deng
- From the ‡Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
- §Graduate School of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiawei Mao
- From the ‡Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
- §Graduate School of Chinese Academy of Sciences, Beijing 100049, China
| | - Yan Wang
- From the ‡Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
- §Graduate School of Chinese Academy of Sciences, Beijing 100049, China
| | - Hanfa Zou
- From the ‡Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
| | - Mingliang Ye
- From the ‡Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China;
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9
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Jamali H, Khan HA, Stringer JR, Chowdhury S, Ellman JA. Identification of multiple structurally distinct, nonpeptidic small molecule inhibitors of protein arginine deiminase 3 using a substrate-based fragment method. J Am Chem Soc 2015; 137:3616-21. [PMID: 25742366 PMCID: PMC4447334 DOI: 10.1021/jacs.5b00095] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The protein arginine deiminases (PADs) are a family of enzymes that catalyze the post-translational hydrolytic deimination of arginine residues. Four different enzymologically active PAD subtypes have been characterized and exhibit tissue-specific expression and association with a number of different diseases. In this Article we describe the development of an approach for the reliable discovery of low molecular weight, nonpeptidic fragment substrates of the PADs that then can be optimized and converted to mechanism-based irreversible PAD inhibitors. The approach is demonstrated by the development of potent and selective inhibitors of PAD3, a PAD subtype implicated in the neurodegenerative response to spinal cord injury. Multiple structurally distinct inhibitors were identified with the most potent inhibitors having >10,000 min(-1) M(-1) k(inact)/K(I) values and ≥10-fold selectivity for PAD3 over PADs 1, 2, and 4.
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Affiliation(s)
- Haya Jamali
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Hasan A. Khan
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | | | | | - Jonathan A. Ellman
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
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10
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Zhao H, Caflisch A. Molecular dynamics in drug design. Eur J Med Chem 2015; 91:4-14. [DOI: 10.1016/j.ejmech.2014.08.004] [Citation(s) in RCA: 136] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Revised: 07/31/2014] [Accepted: 08/03/2014] [Indexed: 11/30/2022]
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11
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Abstract
Fragment hopping is a fragment-based approach to designing biologically active small molecules. The key of this approach is the determination of the minimal pharmacophoric elements in the three-dimensional space. Based on the derived minimal pharmacophoric elements, new fragments with different chemotypes can be generated and positioned to the active site of the target protein. Herein, we detail a protocol for performing fragment hopping. This approach can not only explore a wide chemical space to produce new ligands with novel scaffolds but also characterize and utilize the delicate differences in the active sites between isofunctional proteins to produce new ligands with high target selectivity/specificity.
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Affiliation(s)
- Kevin B Teuscher
- Department of Chemistry, Center for Cell and Genome Science, University of Utah, 315 South 1400 East, Salt Lake City, Utah, 84112-0850, USA
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12
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Catalytic activation of pre-substrates via dynamic fragment assembly on protein templates. Nat Commun 2014; 5:5170. [PMID: 25403979 DOI: 10.1038/ncomms6170] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Accepted: 09/08/2014] [Indexed: 11/09/2022] Open
Abstract
Sensitive detection of small molecule fragments binding to defined sites of biomacromolecules is still a considerable challenge. Here we demonstrate that protein-binding fragments are able to induce enzymatic reactions on the protein surface via dynamic fragment ligation. Fragments binding to the S1 pocket of serine proteases containing a nitrogen, oxygen or sulphur nucleophile are found to activate electrophilic pre-substrates through a reversible, covalent ligation reaction. The dynamic ligation reaction positions the pre-substrate molecule at the active site of the protein thereby inducing its enzymatic cleavage. Catalytic activation of pre-substrates is confirmed by fluorescence spectroscopy and by high-performance liquid chromatography. The approach is investigated with 3 pre-substrates and 14 protein-binding fragments and the specific activation and the templating effect exerted by the enzyme is quantified for each protease-fragment-pre-substrate combination. The described approach enables the site-specific identification of protein-binding fragments, the functional characterization of enzymatic sites and the quantitative analysis of protein template-assisted ligation reactions.
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13
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Gladysz R, Cleenewerck M, Joossens J, Lambeir AM, Augustyns K, Van der Veken P. Repositioning the Substrate Activity Screening (SAS) Approach as a Fragment-Based Method for Identification of Weak Binders. Chembiochem 2014; 15:2238-47. [DOI: 10.1002/cbic.201402192] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Indexed: 11/06/2022]
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14
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Hogan M, Bahta M, Cherry S, Lountos GT, Tropea JE, Zhao BM, Burke TR, Waugh DS, Ulrich RG. Biomolecular Interactions of small-molecule inhibitors affecting the YopH protein tyrosine phosphatase. Chem Biol Drug Des 2013; 81:323-33. [PMID: 23241354 PMCID: PMC3573263 DOI: 10.1111/cbdd.12097] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We have developed competitive and direct binding methods to examine small-molecule inhibitors of protein tyrosine phosphatase activity. Focusing on the Yersinia pestis outer protein H, a potent bacterial protein tyrosine phosphatase, we describe how an understanding of the kinetic interactions involving Yersinia pestis outer protein H, peptide substrates, and small-molecule inhibitors of protein tyrosine phosphatase activity can be beneficial for inhibitor screening, and we further translate these results into a microarray assay for high-throughput screening.
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Affiliation(s)
- Megan Hogan
- United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland 21702, United States
| | - Medhanit Bahta
- Chemical Biology Laboratory, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick National Laboratory for Cancer Research, Frederick, Maryland 21702, United States
| | - Scott Cherry
- Macromolecular Crystallography Laboratory, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick National Lab, Frederick, Maryland 21702, United States
| | - George T. Lountos
- Macromolecular Crystallography Laboratory, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick National Lab, Frederick, Maryland 21702, United States
- Basic Science Program, SAIC-Frederick, Inc., Frederick National Lab, Frederick, Maryland 21702, United States
| | - Joseph E. Tropea
- Macromolecular Crystallography Laboratory, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick National Lab, Frederick, Maryland 21702, United States
| | - Bryan M. Zhao
- United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland 21702, United States
| | - Terrence R. Burke
- Chemical Biology Laboratory, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick National Laboratory for Cancer Research, Frederick, Maryland 21702, United States
| | - David S. Waugh
- Macromolecular Crystallography Laboratory, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick National Lab, Frederick, Maryland 21702, United States
| | - Robert G. Ulrich
- United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland 21702, United States
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15
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Socher E, Grossmann TN. Chemical biology 2012: from drug targets to biological systems and back. Chembiochem 2013. [PMID: 23184865 DOI: 10.1002/cbic.201200697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Multiple sites sharing a common target: This year's EMBO conference on chemical biology encouraged over 340 researchers to come to Heidelberg, Germany, and discuss the use of diverse chemical strategies and tools to investigate biological questions and better understand cellular processes.
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Affiliation(s)
- Elke Socher
- Department of Biology and Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
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16
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Dandapani S, Rosse G, Southall N, Salvino JM, Thomas CJ. Selecting, Acquiring, and Using Small Molecule Libraries for High-Throughput Screening. ACTA ACUST UNITED AC 2012; 4:177-191. [PMID: 26705509 DOI: 10.1002/9780470559277.ch110252] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The selection, acquisition and use of high quality small molecule libraries for screening is an essential aspect of drug discovery and chemical biology programs. Screening libraries continue to evolve as researchers gain a greater appreciation of the suitability of small molecules for specific biological targets, processes and environments. The decisions surrounding the make-up of any given small molecule library is informed by a multitude of variables and opinions vary on best-practices. The fitness of any collection relies upon upfront filtering to avoiding problematic compounds, assess appropriate physicochemical properties, install the ideal level of structural uniqueness and determine the desired extent of molecular complexity. These criteria are under constant evaluation and revision as academic and industrial organizations seek out collections that yield ever improving results from their screening portfolios. Practical questions including cost, compound management, screening sophistication and assay objective also play a significant role in the choice of library composition. This overview attempts to offer advice to all organizations engaged in small molecule screening based upon current best practices and theoretical considerations in library selection and acquisition.
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Affiliation(s)
- Sivaraman Dandapani
- Chemical Biology Platform, The Broad Institute of MIT and Harvard, 7 Cambridge Center, Cambridge Massachusetts 02142 USA
| | - Gerard Rosse
- Dart NeuroScience LLC, 7473 Lusk Boulevard, San Diego, CA 92121 USA
| | - Noel Southall
- NIH Chemical Genomics Center, National Human Genome Research Institute, 9800 Medical Center Drive, MSC 3370 Bethesda, MD 20892-3370 USA
| | - Joseph M Salvino
- Alliance Discovery, Inc, Biotechnology Center 3805 Old Easton Road, Doylestown, PA 18902 USA
| | - Craig J Thomas
- NIH Chemical Genomics Center, National Human Genome Research Institute, 9800 Medical Center Drive, MSC 3370 Bethesda, MD 20892-3370 USA
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17
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van den Berg BHJ, Tholey A. Mass spectrometry-based proteomics strategies for protease cleavage site identification. Proteomics 2012; 12:516-29. [PMID: 22246699 DOI: 10.1002/pmic.201100379] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Revised: 09/14/2011] [Accepted: 09/17/2011] [Indexed: 01/22/2023]
Abstract
Protease-catalyzed hydrolysis of peptide bonds is one of the most pivotal post-translational modifications fulfilling manifold functions in the regulation of cellular processes. Therefore, dysregulation of proteolytic reactions plays a central role in many pathophysiological events. For this reason, understanding the molecular mechanisms in proteolytic reactions, in particular the knowledge of proteases involved in complex processes, expression levels and activity of protease and knowledge of the targeted substrates are an indispensable prerequisite for targeted drug development. The present review focuses on mass spectrometry-based proteomic methods for the analysis of protease cleavage sites, including the identification of the hydrolyzed bonds as well as of the surrounding sequence. Peptide- and protein-centric approaches and bioinformatic tools for experimental data interpretation will be presented and the major advantages and drawbacks of the different approaches will be addressed. The recent applications of these approaches for the analysis of biological function of different protease classes and potential future directions will be discussed.
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Affiliation(s)
- Bart H J van den Berg
- AG Systematische Proteomforschung, Institut für Experimentelle Medizin, Christian-Albrechts-Universität, Kiel, Germany.
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18
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Deu E, Verdoes M, Bogyo M. New approaches for dissecting protease functions to improve probe development and drug discovery. Nat Struct Mol Biol 2012; 19:9-16. [PMID: 22218294 DOI: 10.1038/nsmb.2203] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Proteases are well-established targets for pharmaceutical development because of their known enzymatic mechanism and their regulatory roles in many pathologies. However, many potent clinical lead compounds have been unsuccessful either because of a lack of specificity or because of our limited understanding of the biological roles of the targeted protease. In order to successfully develop protease inhibitors as drugs, it is necessary to understand protease functions and to expand the platform of inhibitor development beyond active site-directed design and in vitro optimization. Several newly developed technologies will enhance assessment of drug selectivity in living cells and animal models, allowing researchers to focus on compounds with high specificity and minimal side effects in vivo. In this review, we highlight advances in the development of chemical probes, proteomic methods and screening tools that we feel will help facilitate this paradigm shift in drug discovery.
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Affiliation(s)
- Edgar Deu
- Department of Pathology, Stanford University School of Medicine, Stanford, California, USA
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19
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Findeisen P, Neumaier M. Functional protease profiling for diagnosis of malignant disease. Proteomics Clin Appl 2011; 6:60-78. [PMID: 22213637 DOI: 10.1002/prca.201100058] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Revised: 09/27/2011] [Accepted: 10/19/2011] [Indexed: 12/24/2022]
Abstract
Clinical proteomic profiling by mass spectrometry (MS) aims at uncovering specific alterations within mass profiles of clinical specimens that are of diagnostic value for the detection and classification of various diseases including cancer. However, despite substantial progress in the field, the clinical proteomic profiling approaches have not matured into routine diagnostic applications so far. Their limitations are mainly related to high-abundance proteins and their complex processing by a multitude of endogenous proteases thus making rigorous standardization difficult. MS is biased towards the detection of low-molecular-weight peptides. Specifically, in serum specimens, the particular fragments of proteolytically degraded proteins are amenable to MS analysis. Proteases are known to be involved in tumour progression and tumour-specific proteases are released into the blood stream presumably as a result of invasive progression and metastasis. Thus, the determination of protease activity in clinical specimens from patients with malignant disease can offer diagnostic and also therapeutic options. The identification of specific substrates for tumour proteases in complex biological samples is challenging, but proteomic screens for proteases/substrate interactions are currently experiencing impressive progress. Such proteomic screens include peptide-based libraries, differential isotope labelling in combination with MS, quantitative degradomic analysis of proteolytically generated neo-N-termini, monitoring the degradation of exogenous reporter peptides with MS, and activity-based protein profiling. In the present article, we summarize and discuss the current status of proteomic techniques to identify tumour-specific protease-substrate interactions for functional protease profiling. Thereby, we focus on the potential diagnostic use of the respective approaches.
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Affiliation(s)
- Peter Findeisen
- Institute for Clinical Chemistry, Medical Faculty Mannheim of the University of Heidelberg, Heidelberg, Germany.
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20
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Edgington LE, Verdoes M, Bogyo M. Functional imaging of proteases: recent advances in the design and application of substrate-based and activity-based probes. Curr Opin Chem Biol 2011; 15:798-805. [PMID: 22098719 DOI: 10.1016/j.cbpa.2011.10.012] [Citation(s) in RCA: 136] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2011] [Revised: 09/25/2011] [Accepted: 10/17/2011] [Indexed: 02/06/2023]
Abstract
Proteases are enzymes that cleave peptide bonds in protein substrates. This process can be important for regulated turnover of a target protein but it can also produce protein fragments that then perform other functions. Because the last few decades of protease research have confirmed that proteolysis is an essential regulatory process in both normal physiology and in multiple disease-associated conditions, there has been an increasing interest in developing methods to image protease activity. Proteases are also considered to be one of the few 'druggable' classes of proteins and therefore a large number of small molecule based inhibitors of proteases have been reported. These compounds serve as a starting point for the design of probes that can be used to target active proteases for imaging applications. Currently, several classes of fluorescent probes have been developed to visualize protease activity in live cells and even whole organisms. The two primary classes of protease probes make use of either peptide/protein substrates or covalent inhibitors that produce a fluorescent signal when bound to an active protease target. This review outlines some of the most recent advances in the design of imaging probes for proteases. In particular, it highlights the strengths and weaknesses of both substrate-based and activity-based probes and their applications for imaging cysteine proteases that are important biomarkers for multiple human diseases.
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Affiliation(s)
- Laura E Edgington
- Cancer Biology Program, Stanford University School of Medicine, 300 Pasteur Dr., Stanford, CA 94305-5324, USA
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21
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Huang D, Caflisch A. Fragment-Based Approaches in Virtual Screening. METHODS AND PRINCIPLES IN MEDICINAL CHEMISTRY 2011. [DOI: 10.1002/9783527633326.ch17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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22
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Bahta M, Lountos GT, Dyas B, Kim SE, Ulrich RG, Waugh DS, Burke TR. Utilization of nitrophenylphosphates and oxime-based ligation for the development of nanomolar affinity inhibitors of the Yersinia pestis outer protein H (YopH) phosphatase. J Med Chem 2011; 54:2933-43. [PMID: 21443195 PMCID: PMC3085962 DOI: 10.1021/jm200022g] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Our current study reports the first K(M) optimization of a library of nitrophenylphosphate-containing substrates for generating an inhibitor lead against the Yersinia pestis outer protein phosphatase (YopH). A high activity substrate identified by this method (K(M) = 80 μM) was converted from a substrate into an inhibitor by replacement of its phosphate group with difluoromethylphosphonic acid and by attachment of an aminooxy handle for further structural optimization by oxime ligation. A cocrystal structure of this aminooxy-containing platform in complex with YopH allowed the identification of a conserved water molecule proximal to the aminooxy group that was subsequently employed for the design of furanyl-based oxime derivatives. By this process, a potent (IC(50) = 190 nM) and nonpromiscuous inhibitor was developed with good YopH selectivity relative to a panel of phosphatases. The inhibitor showed significant inhibition of intracellular Y. pestis replication at a noncytotoxic concentration. The current work presents general approaches to PTP inhibitor development that may be useful beyond YopH.
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Affiliation(s)
- Medhanit Bahta
- Chemical Biology Laboratory, Molecular Discovery Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, NCI-Frederick, Frederick, MD 21702, U.S.A
| | - George T. Lountos
- Macromolecular Crystallography Laboratory, Center for Cancer Research, National Cancer Institute, National Institutes of Health, NCI-Frederick, Frederick, MD 21702, U.S.A
| | - Beverly Dyas
- Laboratory of Molecular Immunology, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland 21702, U.S.A
| | - Sung-Eun Kim
- Chemical Biology Laboratory, Molecular Discovery Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, NCI-Frederick, Frederick, MD 21702, U.S.A
| | - Robert G. Ulrich
- Laboratory of Molecular Immunology, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland 21702, U.S.A
| | - David S. Waugh
- Macromolecular Crystallography Laboratory, Center for Cancer Research, National Cancer Institute, National Institutes of Health, NCI-Frederick, Frederick, MD 21702, U.S.A
| | - Terrence R. Burke
- Chemical Biology Laboratory, Molecular Discovery Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, NCI-Frederick, Frederick, MD 21702, U.S.A
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23
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24
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Drag M, Bogyo M, Ellman JA, Salvesen GS. Aminopeptidase fingerprints, an integrated approach for identification of good substrates and optimal inhibitors. J Biol Chem 2009; 285:3310-8. [PMID: 19948737 DOI: 10.1074/jbc.m109.060418] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Aminopeptidases process the N-terminal amino acids of target substrates by sequential cleavage of one residue at a time. They are found in all cell compartments of prokaryotes and eukaryotes, being implicated in the major proteolytic events of cell survival, defense, growth, and development. We present a new approach for the fast and reliable evaluation of the substrate specificity of individual aminopeptidases. Using solid phase chemistry with the 7-amino-4-carbamoylmethylcoumarin fluorophore, we have synthesized a library of 61 individual natural and unnatural amino acids substrates, chosen to cover a broad spectrum of the possible interactions in the S1 pocket of this type of protease. As proof of concept, we determined the substrate specificity of human, pig, and rat orthologs of aminopeptidase N (CD13), a highly conserved cell surface protease that inactivates enkephalins and other bioactive peptides. Our data reveal a large and hydrophobic character for the S1 pocket of aminopeptidase N that is conserved with aminopeptidase Ns. Our approach, which can be applied in principle to all aminopeptidases, yields useful information for the design of specific inhibitors, and more importantly, reveals a relationship between the kinetics of substrate hydrolysis and the kinetics of enzyme inhibition.
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Affiliation(s)
- Marcin Drag
- Apoptosis and Cell Death Research Program, the Burnham Institute for Medical Research, La Jolla, California 92037, USA.
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25
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Orita M, Warizaya M, Amano Y, Ohno K, Niimi T. Advances in fragment-based drug discovery platforms. Expert Opin Drug Discov 2009; 4:1125-44. [DOI: 10.1517/17460440903317580] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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26
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Schmidt MF, Rademann J. Dynamic template-assisted strategies in fragment-based drug discovery. Trends Biotechnol 2009; 27:512-21. [PMID: 19679363 PMCID: PMC7114311 DOI: 10.1016/j.tibtech.2009.06.001] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2009] [Revised: 06/16/2009] [Accepted: 06/17/2009] [Indexed: 11/27/2022]
Abstract
Fragment-based methods for drug discovery are increasingly popular because they provide drug leads with greater ligand efficiency than conventional high-throughput screening. However, established methods for fragment detection do not address the central question in fragment-based ligand discovery: how can a primary ligand be optimally extended by a secondary fragment? Dynamic screening methods solve this issue by using a protein target as a template for ligand assembly, thus yielding high-affinity binders from low-affinity fragments. This review summarizes recent work on dynamic screening methodology, which resulted in the development of several high-affinity binders for various targets. Strengths and limitations of the published approaches are discussed and possible contributions of dynamic screening methodology to the drug discovery process are highlighted.
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Affiliation(s)
- Marco F Schmidt
- Department of Medicinal Chemistry, Leibniz-Institute of Molecular Pharmacology, Robert-Rössle-Strasse 10, 13125 Berlin, Germany
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27
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Lim MD, Craik CS. Using specificity to strategically target proteases. Bioorg Med Chem 2009; 17:1094-100. [PMID: 18434168 PMCID: PMC2663002 DOI: 10.1016/j.bmc.2008.03.068] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2007] [Revised: 03/18/2008] [Accepted: 03/24/2008] [Indexed: 01/05/2023]
Abstract
Proteases are a family of naturally occurring enzymes in the body whose dysregulation has been implicated in numerous diseases and cancers. Their ability to selectively and catalytically turnover substrate adds both signal amplification and functionality as parameters for the detection of disease. This review will focus on the development of activity-based methodologies to characterize proteases, and in particular, the use of positional scanning, synthetic combinatorial libraries (PS-SCL's), and substrate activity screening (SAS) assays. The use of these approaches to better understand a protease's natural substrate will be discussed as well as the technologies that emerged.
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Affiliation(s)
- Mark D Lim
- Department of Pharmaceutical Chemistry, University of California, School of Pharmacy, 513 Parnassus Avenue Room S-926, San Francisco, CA 94158, USA
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28
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29
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Smith BC, Hallows WC, Denu JM. Mechanisms and molecular probes of sirtuins. CHEMISTRY & BIOLOGY 2008; 15:1002-13. [PMID: 18940661 PMCID: PMC2626554 DOI: 10.1016/j.chembiol.2008.09.009] [Citation(s) in RCA: 114] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2008] [Revised: 09/08/2008] [Accepted: 09/17/2008] [Indexed: 12/12/2022]
Abstract
Sirtuins are critical regulators of many cellular processes, including insulin secretion, the cell cycle, and apoptosis. Sirtuins are associated with a variety of age-associated diseases such as type II diabetes, obesity, and Alzheimer's disease. A thorough understanding of sirtuin chemical mechanisms will aid toward developing novel therapeutics that regulate metabolic disorders and combat associated diseases. In this review, we discuss the unique deacetylase mechanism of sirtuins and how this information might be employed to develop inhibitors and other molecular probes for therapeutic and basic research applications. We also cover physiological regulation of sirtuin activity and how these modes of regulation may be exploited to manipulate sirtuin activity in live cells. Development of molecular probes and drugs that specifically target sirtuins will further understanding of sirtuin biology and potentially afford new treatments of several human diseases.
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Affiliation(s)
- Brian C. Smith
- Department of Biomolecular Chemistry; University of Wisconsin, Medical School; Madison, WI 53706; USA
| | - William C. Hallows
- Department of Biomolecular Chemistry; University of Wisconsin, Medical School; Madison, WI 53706; USA
| | - John M. Denu
- Department of Biomolecular Chemistry; University of Wisconsin, Medical School; Madison, WI 53706; USA
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