1
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Wyatt JW, Korasick DA, Qureshi IA, Campbell AC, Gates KS, Tanner JJ. Inhibition, crystal structures, and in-solution oligomeric structure of aldehyde dehydrogenase 9A1. Arch Biochem Biophys 2020; 691:108477. [PMID: 32717224 DOI: 10.1016/j.abb.2020.108477] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 06/19/2020] [Accepted: 06/20/2020] [Indexed: 10/23/2022]
Abstract
Aldehyde dehydrogenase 9A1 (ALDH9A1) is a human enzyme that catalyzes the NAD+-dependent oxidation of the carnitine precursor 4-trimethylaminobutyraldehyde to 4-N-trimethylaminobutyrate. Here we show that the broad-spectrum ALDH inhibitor diethylaminobenzaldehyde (DEAB) reversibly inhibits ALDH9A1 in a time-dependent manner. Possible mechanisms of inhibition include covalent reversible inactivation involving the thiohemiacetal intermediate and slow, tight-binding inhibition. Two crystal structures of ALDH9A1 are reported, including the first of the enzyme complexed with NAD+. One of the structures reveals the active conformation of the enzyme, in which the Rossmann dinucleotide-binding domain is fully ordered and the inter-domain linker adopts the canonical β-hairpin observed in other ALDH structures. The oligomeric structure of ALDH9A1 was investigated using analytical ultracentrifugation, small-angle X-ray scattering, and negative stain electron microscopy. These data show that ALDH9A1 forms the classic ALDH superfamily dimer-of-dimers tetramer in solution. Our results suggest that the presence of an aldehyde substrate and NAD+ promotes isomerization of the enzyme into the active conformation.
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Affiliation(s)
- Jesse W Wyatt
- Department of Chemistry, University of Missouri, Columbia, MO, 65211, United States
| | - David A Korasick
- Department of Biochemistry, University of Missouri, Columbia, MO, 65211, United States
| | - Insaf A Qureshi
- Department of Biotechnology & Bioinformatics, School of Life Sciences, University of Hyderabad, Prof. C.R. Rao Road, Hyderabad, 500046, India
| | - Ashley C Campbell
- Department of Biochemistry, University of Missouri, Columbia, MO, 65211, United States
| | - Kent S Gates
- Department of Chemistry, University of Missouri, Columbia, MO, 65211, United States; Department of Biochemistry, University of Missouri, Columbia, MO, 65211, United States
| | - John J Tanner
- Department of Chemistry, University of Missouri, Columbia, MO, 65211, United States; Department of Biochemistry, University of Missouri, Columbia, MO, 65211, United States.
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2
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Singh N, Bhattacharyya D. Cholesterol and Its Derivatives Reversibly Inhibit Proteinase K. J Cell Physiol 2016; 232:596-609. [DOI: 10.1002/jcp.25457] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2016] [Accepted: 06/13/2016] [Indexed: 12/13/2022]
Affiliation(s)
- Namrata Singh
- Division of Structural Biology and Bioinformatics; CSIR-Indian Institute of Chemical Biology; Jadavpur Kolkata India
| | - Debasish Bhattacharyya
- Division of Structural Biology and Bioinformatics; CSIR-Indian Institute of Chemical Biology; Jadavpur Kolkata India
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3
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Cabrera-Muñoz A, Rojas L, Gil DF, González-González Y, Mansur M, Camejo A, Pires JR, Alonso-Del-Rivero Antigua M. Heterologous expression of Cenchritis muricatus protease inhibitor II (CmPI-II) in Pichia pastoris system: Purification, isotopic labeling and preliminary characterization. Protein Expr Purif 2016; 126:127-136. [PMID: 27353494 DOI: 10.1016/j.pep.2016.06.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 06/23/2016] [Accepted: 06/24/2016] [Indexed: 10/21/2022]
Abstract
Cenchritis muricatus protease inhibitor II (CmPI-II) is a tight-binding serine protease inhibitor of the Kazal family with an atypical broad specificity, being active against several proteases such as bovine pancreatic trypsin, human neutrophil elastase and subtilisin A. CmPI-II 3D structures are necessary for understanding the molecular basis of its activity. In the present work, we describe an efficient and straightforward recombinant expression strategy, as well as a cost-effective procedure for isotope labeling for NMR structure determination purposes. The vector pCM101 containing the CmPI-II gene, under the control of Pichia pastoris AOX1 promoter was constructed. Methylotrophic Pichia pastoris strain KM71H was then transformed with the plasmid and the recombinant protein (rCmPI-II) was expressed in benchtop fermenter in unlabeled or (15)N-labeled forms using ammonium chloride ((15)N, 99%) as the sole nitrogen source. Protein purification was accomplished by sequential cation exchange chromatography in STREAMLINE DirectHST, anion exchange chromatography on Hitrap Q-Sepharose FF and gel filtration on Superdex 75 10/30, yielding high quantities of pure rCmPI-II and (15)N rCmPI-II. Recombinant proteins displayed similar functional features as compared to the natural inhibitor and NMR spectra indicated folded and homogeneously labeled samples, suitable for further studies of structure and protease-inhibitor interactions.
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Affiliation(s)
- Aymara Cabrera-Muñoz
- Centro de Estudios de Proteínas, Facultad de Biología, Universidad de La Habana, Ciudad de La Habana-Cuba, Calle 25 No 455, Vedado, La Habana, Cuba.
| | - Laritza Rojas
- Centro de Estudios de Proteínas, Facultad de Biología, Universidad de La Habana, Ciudad de La Habana-Cuba, Calle 25 No 455, Vedado, La Habana, Cuba.
| | - Dayrom F Gil
- Centro de Estudios de Proteínas, Facultad de Biología, Universidad de La Habana, Ciudad de La Habana-Cuba, Calle 25 No 455, Vedado, La Habana, Cuba.
| | - Yamile González-González
- Centro de Estudios de Proteínas, Facultad de Biología, Universidad de La Habana, Ciudad de La Habana-Cuba, Calle 25 No 455, Vedado, La Habana, Cuba.
| | - Manuel Mansur
- Institut de Biotecnología i de Biomedicina, Universitat Autònoma de Barcelona, Campus Universitari, 08193, Bellaterra, Cerdanyola del Vallès, Barcelona, Spain.
| | - Ayamey Camejo
- Centro de Estudios de Proteínas, Facultad de Biología, Universidad de La Habana, Ciudad de La Habana-Cuba, Calle 25 No 455, Vedado, La Habana, Cuba.
| | - José R Pires
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Av. Carlos Chagas Filho, 373 - Bloco E, Sala 10, 21941-902, Rio de Janeiro, RJ, Brazil.
| | - Maday Alonso-Del-Rivero Antigua
- Centro de Estudios de Proteínas, Facultad de Biología, Universidad de La Habana, Ciudad de La Habana-Cuba, Calle 25 No 455, Vedado, La Habana, Cuba.
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4
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Huang JH, Han D, Ruggles ME, Jayaraman A, Ugaz VM. Characterization of enzymatic micromachining for construction of variable cross-section microchannel topologies. BIOMICROFLUIDICS 2016; 10:033102. [PMID: 27190566 PMCID: PMC4859826 DOI: 10.1063/1.4948508] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 04/20/2016] [Indexed: 05/10/2023]
Abstract
The ability to harness enzymatic activity as an etchant to precisely machine biodegradable substrates introduces new possibilities for microfabrication. This flow-based etching is straightforward to implement, enabling patterning of microchannels with topologies that incorporate variable depth along the cross-sectional dimension. Additionally, unlike conventional small-molecule formulations, the macromolecular nature of enzymatic etchants enables features to be precisely positioned. Here, we introduce a kinetic model to characterize the enzymatic machining process and its localization by co-injection of a macromolecular inhibitor species. Our model captures the interaction between enzyme, inhibitor, and substrate under laminar flow, enabling rational prediction of etched microchannel profiles so that cross-sectional topologies incorporating complex lateral variations in depth can be constructed. We also apply this approach to achieve simultaneous widening of an entire network of microchannels produced in the biodegradable polymeric substrate poly(lactic acid), laying a foundation to construct systems incorporating a broad range of internal cross-sectional dimensions by manipulating the process conditions.
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Affiliation(s)
- Jen-Huang Huang
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas 77843-3122, USA
| | - Duanduan Han
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas 77843-3122, USA
| | - Molly E Ruggles
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas 77843-3122, USA
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5
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Sharma K, Mukherjee C, Roy S, De D, Bhattacharyya D. Human placental extract mediated inhibition of proteinase K: implications of heparin and glycoproteins in wound physiology. J Cell Physiol 2014; 229:1212-23. [PMID: 24435659 DOI: 10.1002/jcp.24555] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 01/10/2014] [Indexed: 12/11/2022]
Abstract
Efficient debridement of the wound bed following the removal of microbial load prevents its progression into a chronic wound. Bacterial infection and excessive proteolysis characterize impaired healing and therefore, their inhibition might restore the disturbed equilibrium in the healing process. Human placental extract exhibits reversible, non-competitive inhibition towards Proteinase K, a microbial protease, by stabilizing it against auto-digestion. Scattering and fluorescence studies followed by biochemical analysis indicated the involvement of a glycan moiety. Surface plasmon resonance demonstrated specific interaction of heparin with Proteinase K having Kd in μM range. Further, Proteinase K contains sequence motifs similar to other heparin-binding proteins. Molecular docking revealed presence of clefts suitable for binding of heparin-derived oligosaccharides. Comprehensive analysis of this inhibitory property of placental extract partly explains its efficacy in curing wounds with common bacterial infections.
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Affiliation(s)
- Kanika Sharma
- Division of Structural Biology and Bioinformatics, CSIR-Indian Institute of Chemical Biology, Jadavpur, Kolkata, India
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6
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Srivastava A, Meena SK, Alam M, Nayeem SM, Deep S, Sau AK. Structural and Functional Insights into the Regulation of Helicobacter pylori Arginase Activity by an Evolutionary Nonconserved Motif. Biochemistry 2013; 52:508-19. [DOI: 10.1021/bi301421v] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Abhishek Srivastava
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi 110 067,
India
| | - Shiv Kumar Meena
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi 110 067,
India
| | - Mashkoor Alam
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi 110 067,
India
| | - Shahid M. Nayeem
- Department of Chemistry, Indian Institute of Technology, New Delhi 110 016,
India
| | - Shashank Deep
- Department of Chemistry, Indian Institute of Technology, New Delhi 110 016,
India
| | - Apurba Kumar Sau
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi 110 067,
India
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7
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Bassett EA, Wang W, Rastinejad F, El-Deiry WS. Structural and functional basis for therapeutic modulation of p53 signaling. Clin Cancer Res 2008; 14:6376-86. [PMID: 18927276 DOI: 10.1158/1078-0432.ccr-08-1526] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Effective modulation of structural features and/or functional properties of the major tumor suppressor p53 as a wild-type or cancer-associated mutant protein represents a major challenge in drug development for cancer. p53 is an attractive target for therapeutic design because of its involvement as a mediator of growth arrest and apoptosis after exposure to chemoradiotherapy and/or radiotherapy. Although most clinically used cytotoxic agents target stabilization of wild-type p53, there are a number of approaches that hold promise for reactivation of mutant p53. On the other hand, brief blockade of p53 may reduce toxicity from systemic cytotoxic therapy. Screens for restoration of p53 transcriptional responses in p53-deficient cells may provide a functional means to develop anticancer therapeutics. Structure-based modulation continues to hold promise for development of peptides or small molecules capable of modulation of either wild-type or mutant p53 proteins.
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Affiliation(s)
- Emily A Bassett
- Department of Medicine, The Abramson Comprehensive Cancer Center, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA
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8
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Slováková M, Peyrin JM, Bílková Z, Juklíčková M, Hernychová L, Viovy JL. Magnetic Proteinase K Reactor as a New Tool for Reproducible Limited Protein Digestion. Bioconjug Chem 2008; 19:966-72. [DOI: 10.1021/bc7004413] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Marcela Slováková
- Laboratoire Physicochimie-Curie, Institut Curie, Paris Cedex 5, France, Unité de Virologie Immunologie Moléculaires, INRA, 78350 Jouy-en-Josas, France, Department of Biological and Biochemical Sciences, University of Pardubice, 53210 Pardubice, Czech Republic, and Institute of Molecular Pathology, University of Defence, Hradec Králové, Czech Republic
| | - Jean-Michel Peyrin
- Laboratoire Physicochimie-Curie, Institut Curie, Paris Cedex 5, France, Unité de Virologie Immunologie Moléculaires, INRA, 78350 Jouy-en-Josas, France, Department of Biological and Biochemical Sciences, University of Pardubice, 53210 Pardubice, Czech Republic, and Institute of Molecular Pathology, University of Defence, Hradec Králové, Czech Republic
| | - Zuzana Bílková
- Laboratoire Physicochimie-Curie, Institut Curie, Paris Cedex 5, France, Unité de Virologie Immunologie Moléculaires, INRA, 78350 Jouy-en-Josas, France, Department of Biological and Biochemical Sciences, University of Pardubice, 53210 Pardubice, Czech Republic, and Institute of Molecular Pathology, University of Defence, Hradec Králové, Czech Republic
| | - Martina Juklíčková
- Laboratoire Physicochimie-Curie, Institut Curie, Paris Cedex 5, France, Unité de Virologie Immunologie Moléculaires, INRA, 78350 Jouy-en-Josas, France, Department of Biological and Biochemical Sciences, University of Pardubice, 53210 Pardubice, Czech Republic, and Institute of Molecular Pathology, University of Defence, Hradec Králové, Czech Republic
| | - Lenka Hernychová
- Laboratoire Physicochimie-Curie, Institut Curie, Paris Cedex 5, France, Unité de Virologie Immunologie Moléculaires, INRA, 78350 Jouy-en-Josas, France, Department of Biological and Biochemical Sciences, University of Pardubice, 53210 Pardubice, Czech Republic, and Institute of Molecular Pathology, University of Defence, Hradec Králové, Czech Republic
| | - Jean-Louis Viovy
- Laboratoire Physicochimie-Curie, Institut Curie, Paris Cedex 5, France, Unité de Virologie Immunologie Moléculaires, INRA, 78350 Jouy-en-Josas, France, Department of Biological and Biochemical Sciences, University of Pardubice, 53210 Pardubice, Czech Republic, and Institute of Molecular Pathology, University of Defence, Hradec Králové, Czech Republic
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9
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Xue QG, Waldrop GL, Schey KL, Itoh N, Ogawa M, Cooper RK, Losso JN, La Peyre JF. A novel slow-tight binding serine protease inhibitor from eastern oyster (Crassostrea virginica) plasma inhibits perkinsin, the major extracellular protease of the oyster protozoan parasite Perkinsus marinus. Comp Biochem Physiol B Biochem Mol Biol 2006; 145:16-26. [PMID: 16872855 DOI: 10.1016/j.cbpb.2006.05.010] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2005] [Revised: 05/26/2006] [Accepted: 05/27/2006] [Indexed: 12/20/2022]
Abstract
A serine protease inhibitor was purified from plasma of the eastern oyster, Crassostrea virginica. The inhibitor is a 7609.6 Da protein consisting of 71 amino acids with 12 cysteine residues that are postulated to form 6 intra-chain disulfide bridges. Sequencing of the cloned cDNA identified an open reading frame encoding a polypeptide of 90 amino acids, with the 19 N-terminal amino acids forming a signal peptide. No sequence similarity with known proteins was found in sequence databases. The protein inhibited the serine proteases subtilisin A, trypsin and perkinsin, the major extracellular protease of the oyster protozoan parasite, Perkinsus marinus, in a slow binding manner. The mechanism of inhibition involves a rapid binding of inhibitor to the enzyme to form a weak enzyme-inhibitor complex followed by a slow isomerization to form a very tight binding enzyme-inhibitor complex. The overall dissociation constants K(i) with subtilisin A, perkinsin and trypsin were 0.29 nM, 13.7 nM and 17.7 nM, respectively. No inhibition of representatives of the other protease classes was detected. This is the first protein inhibitor of proteases identified from a bivalve mollusk and it represents a new protease inhibitor family. Its tight binding to subtilisin and perkinsin suggests it plays a role in the oyster host defense against P. marinus.
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Affiliation(s)
- Qing-Gang Xue
- Cooperative Aquatic Animal Health Research Program, Department of Veterinary Science, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA
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10
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Madeo J, Gunner MR. Modeling binding kinetics at the Q(A) site in bacterial reaction centers. Biochemistry 2005; 44:10994-1004. [PMID: 16101283 PMCID: PMC2727067 DOI: 10.1021/bi050544j] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Bacterial reaction centers (RCs) catalyze a series of electron-transfer reactions reducing a neutral quinone to a bound, anionic semiquinone. The dissociation constants and association rates of 13 tailless neutral and anionic benzo- and naphthoquinones for the Q(A) site were measured and compared. The K(d) values for these quinones range from 0.08 to 90 microM. For the eight neutral quinones, including duroquinone (DQ) and 2,3-dimethoxy-5-methyl-1,4-benzoquinone (UQ(0)), the quinone concentration and solvent viscosity dependence of the association rate indicate a second-order rate-determining step. The association rate constants (k(on)) range from 10(5) to 10(7) M(-)(1) s(-)(1). Association and dissociation rate constants were determined at pH values above the hydroxyl pK(a) for five hydroxyl naphthoquinones. These negatively charged compounds are competitive inhibitors for the Q(A) site. While the neutral quinones reach equilibrium in milliseconds, anionic hydroxyl quinones with similar K(d) values take minutes to bind or dissociate. These slow rates are independent of ionic strength, solvent viscosity, and quinone concentration, indicating a first-order rate-limiting step. The anionic semiquinone, formed by forward electron transfer at the Q(A) site, also dissociates slowly. It is not possible to measure the association rate of the unstable semiquinone. However, as the protein creates kinetic barriers for binding and releasing anionic hydroxyl quinones without greatly increasing the affinity relative to neutral quinones, it is suggested that the Q(A) site may do the same for anionic semiquinone. Thus, the slow semiquinone dissociation may not indicate significant thermodynamic stabilization of the reduced species in the Q(A) site.
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Affiliation(s)
- Jennifer Madeo
- Physics Department J-419 City College of New York 138th Street and Convent Avenue, New York, New York 10031
| | - M. R. Gunner
- Physics Department J-419 City College of New York 138th Street and Convent Avenue, New York, New York 10031
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11
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Chang CF, Ho CW, Wu CY, Chao TA, Wong CH, Lin CH. Discovery of picomolar slow tight-binding inhibitors of alpha-fucosidase. ACTA ACUST UNITED AC 2005; 11:1301-6. [PMID: 15380190 DOI: 10.1016/j.chembiol.2004.07.009] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2004] [Revised: 06/27/2004] [Accepted: 07/14/2004] [Indexed: 11/26/2022]
Abstract
Glycosidase inhibitors have shown great medicinal and pharmaceutical values as exemplified by the therapeutic treatment of influenza virus and non-insulin-dependent diabetes. We herein report the discovery of picomolar slow tight-binding inhibitors 2-5 against the alpha-fucosidase from Corynebacterium sp. by a rapid screening for an optimal aglycon attached to 1-aminomethyl fuconojirimycin (1). The time-dependent inhibition displays the progressive tightening of enzyme-inhibitor complex from a low nanomolar K(i) to picomolar K(i)* value. Particularly compound 2 with a K(i)* of 0.46 pM represents the most potent glycosidase inhibitor to date. The effect of compound 3 on the intrinsic fluorescence of alpha-fucosidase is both time- and concentration-dependent in a saturation-type manner, which is consistent with the initial formation of a rapid equilibrium complex of enzyme and inhibitor (E.I), followed by the slower formation of a tightly bound enzyme-inhibitor complex (E.I*). The binding affinity increases 3.5 x 10(4)-fold from 1 (K(i) = 16.3 nM) to 2 (K(i)* = 0.46 pM). This work clearly demonstrates the effectiveness of our combinatorial approach leading to the rapid discovery of potent inhibitors.
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Affiliation(s)
- Chuan-Fa Chang
- The Genomic Research Center and Institute of Biological Chemistry, Academia Sinica, No. 128 Academia Road Section 2, Nan-Kang, Taipei 11529, Taiwan
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12
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Perdicakis B, Montgomery HJ, Guillemette JG, Jervis E. Analysis of slow-binding enzyme inhibitors at elevated enzyme concentrations. Anal Biochem 2005; 337:211-23. [PMID: 15691501 DOI: 10.1016/j.ab.2004.11.012] [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: 07/29/2004] [Indexed: 10/26/2022]
Abstract
The improvement in the characterization of slow-binding inhibitors achieved by performing experiments at elevated enzyme concentrations is presented. In particular, the characterization of slow-binding inhibitors conforming to a two-step mode of inhibition with a steady-state dissociation constant that is much lower than the initial dissociation constant with enzyme is discussed. For these systems, inhibition is rapid and low steady-state product concentrations are produced at saturating inhibitor concentrations. By working at elevated enzyme concentrations, improved signal-to-noise ratios are achieved and data may be collected at saturating inhibitor levels. Numerical simulations confirmed that improved parameter estimates are obtained and useful data to discern the mechanism of slow-binding inhibition are produced by working at elevated enzyme concentrations. The saturation kinetics that were unobservable in two previous studies of an enzyme inhibitor system were measured by performing experiments at an elevated enzyme concentration. These results indicate that consideration of the quality of the data acquired using a particular assay is an important factor when selecting the enzyme concentration at which to perform experiments used to characterize the class of enzyme inhibitors examined herein.
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Affiliation(s)
- Basil Perdicakis
- Department of Chemical Engineering, University of Waterloo, Waterloo, Ont., Canada N2L 3G1
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13
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Issaeva N, Bozko P, Enge M, Protopopova M, Verhoef LGGC, Masucci M, Pramanik A, Selivanova G. Small molecule RITA binds to p53, blocks p53-HDM-2 interaction and activates p53 function in tumors. Nat Med 2004; 10:1321-8. [PMID: 15558054 DOI: 10.1038/nm1146] [Citation(s) in RCA: 545] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2004] [Accepted: 10/14/2004] [Indexed: 01/27/2023]
Abstract
In tumors that retain wild-type p53, its tumor-suppressor function is often impaired as a result of the deregulation of HDM-2, which binds to p53 and targets it for proteasomal degradation. We have screened a chemical library and identified a small molecule named RITA (reactivation of p53 and induction of tumor cell apoptosis), which bound to p53 and induced its accumulation in tumor cells. RITA prevented p53-HDM-2 interaction in vitro and in vivo and affected p53 interaction with several negative regulators. RITA induced expression of p53 target genes and massive apoptosis in various tumor cells lines expressing wild-type p53. RITA suppressed the growth of human fibroblasts and lymphoblasts only upon oncogene expression and showed substantial p53-dependent antitumor effect in vivo. RITA may serve as a lead compound for the development of an anticancer drug that targets tumors with wild-type p53.
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Affiliation(s)
- Natalia Issaeva
- Microbiology and Tumor Biology Center, Karolinska Institutet, SE-171 77 Stockholm, Sweden
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