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Dike PP, Bhowmick S, Eldesoky GE, Wabaidur SM, Patil PC, Islam MA. In silico identification of small molecule modulators for disruption of Hsp90-Cdc37 protein-protein interaction interface for cancer therapeutic application. J Biomol Struct Dyn 2020; 40:2082-2098. [PMID: 33095103 DOI: 10.1080/07391102.2020.1835714] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The protein-protein interactions (PPIs) in the biological systems are important to maintain a number of cellular processes. Several disorders including cancer may be developed due to dysfunction in the assembly of PPI networks. Hence, targeting intracellular PPIs can be considered as a crucial drug target for cancer therapy. Among the enormous and diverse group of cancer-enabling PPIs, the Hsp90-Cdc37 is prominent for cancer therapeutic development. The successful inhibition of Hsp90-Cdc37 PPI interface can be an important therapeutic option for cancer management. In the current study, a set of more than sixty thousand compounds belong to four databases were screened through a multi-steps molecular docking study in Glide against the Hsp90-Cdc37 interaction interface. The Glide-score and Prime-MM-GBSA based binding free energy of DCZ3112, standard Hsp90-Cdc37 inhibitor were found to be -6.96 and -40.46 kcal/mol, respectively. The above two parameters were used as cut-off score to reduce the chemical space from all successfully docked molecules. Furthermore, the in-silico pharmacokinetics parameters, common-feature pharmacophore analyses and the molecular binding interactions were used to wipe out the inactive molecules. Finally, four molecules were found to be important to modulate the Hsp90-Cdc37 interface. The potentiality of the final four molecules was checked through several drug-likeness characteristics. The molecular dynamics (MD) simulation study explained that all four molecules retained inside the interface of Hsp90-Cdc37. The binding free energy of each molecule obtained from the MD simulation trajectory was clearly explained the strong affection towards the Hsp90-Cdc37. Hence, the proposed molecule might be crucial for successful inhibition of the Hsp90-Cdc37 interface.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Prajakta Prakash Dike
- Department of Bioinformatics, Rajiv Gandhi Institute of IT and Biotechnology, Bharati Vidyapeeth Deemed University, Pune, India
| | - Shovonlal Bhowmick
- Department of Chemical Technology, University of Calcutta, Kolkata, India
| | - Gaber E Eldesoky
- Department of Chemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Saikh M Wabaidur
- Department of Chemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Preeti Chunarkar Patil
- Department of Bioinformatics, Rajiv Gandhi Institute of IT and Biotechnology, Bharati Vidyapeeth Deemed University, Pune, India
| | - Md Ataul Islam
- Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.,School of Health Sciences, University of Kwazulu-Natal, Durban, South Africa.,Department of Chemical Pathology, Faculty of Health Sciences, University of Pretoria and National Health Laboratory Service Tshwane Academic Division, Pretoria, South Africa
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2
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Zhong M, Lynch A, Muellers SN, Jehle S, Luo L, Hall DR, Iwase R, Carolan JP, Egbert M, Wakefield A, Streu K, Harvey CM, Ortet PC, Kozakov D, Vajda S, Allen KN, Whitty A. Interaction Energetics and Druggability of the Protein-Protein Interaction between Kelch-like ECH-Associated Protein 1 (KEAP1) and Nuclear Factor Erythroid 2 Like 2 (Nrf2). Biochemistry 2020; 59:563-581. [PMID: 31851823 PMCID: PMC8177486 DOI: 10.1021/acs.biochem.9b00943] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Development of small molecule inhibitors of protein-protein interactions (PPIs) is hampered by our poor understanding of the druggability of PPI target sites. Here, we describe the combined application of alanine-scanning mutagenesis, fragment screening, and FTMap computational hot spot mapping to evaluate the energetics and druggability of the highly charged PPI interface between Kelch-like ECH-associated protein 1 (KEAP1) and nuclear factor erythroid 2 like 2 (Nrf2), an important drug target. FTMap identifies four binding energy hot spots at the active site. Only two of these are exploited by Nrf2, which alanine scanning of both proteins shows to bind primarily through E79 and E82 interacting with KEAP1 residues S363, R380, R415, R483, and S508. We identify fragment hits and obtain X-ray complex structures for three fragments via crystal soaking using a new crystal form of KEAP1. Combining these results provides a comprehensive and quantitative picture of the origins of binding energy at the interface. Our findings additionally reveal non-native interactions that might be exploited in the design of uncharged synthetic ligands to occupy the same site on KEAP1 that has evolved to bind the highly charged DEETGE binding loop of Nrf2. These include π-stacking with KEAP1 Y525 and interactions at an FTMap-identified hot spot deep in the binding site. Finally, we discuss how the complementary information provided by alanine-scanning mutagenesis, fragment screening, and computational hot spot mapping can be integrated to more comprehensively evaluate PPI druggability.
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Affiliation(s)
| | | | | | | | | | - David R Hall
- Acpharis, Inc. , 160 North Mill Street , Holliston , Massachusetts 01746 , United States
| | | | | | | | | | | | | | | | - Dima Kozakov
- Department of Applied Mathematics , Stony Brook University , Stony Brook , New York 11794 , United States
| | - Sandor Vajda
- Biomolecular Engineering Research Center , Boston University , Boston , Massachusetts 02215 , United States
| | - Karen N Allen
- Biomolecular Engineering Research Center , Boston University , Boston , Massachusetts 02215 , United States
| | - Adrian Whitty
- Biomolecular Engineering Research Center , Boston University , Boston , Massachusetts 02215 , United States
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3
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Protein-protein complexes as targets for drug discovery against infectious diseases. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2019; 121:237-251. [PMID: 32312423 DOI: 10.1016/bs.apcsb.2019.11.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Antibiotics are therapeutic agents against bacterial infections, however, the emergence of multiple and extremely drug-resistant microbes (Multi-Drug Resistant and Extremely Drug-Resistant) are compromising the effectiveness of the currently available treatment options. The drug resistance is not a novel crisis, the current pace of drug discovery has failed to compete with the growth of MDR and XDR pathogenic strains and therefore, it is highly central to find out novel antimicrobial drugs with unique mechanisms of action which may reduce the burden of MDR and XDR pathogenic strains. Protein-protein interactions (PPIs) are involved in a countless of the physiological and cellular phenomena and have become an attractive target to treat the diseases. Therefore, targeting PPIs in infectious agents may offer a completely novel strategy of intervention to develop anti-infective drugs that may combat the ever-increasing rate of drug resistant strains. This chapter describes how small molecule candidate inhibitors that are capable of disrupting the PPIs in pathogenic microbes and it could be an alternative lead discovery strategy to obtain novel antibiotics. Over the last three decades, there has been increasing efforts focused on the manipulation of PPIs in order to develop novel therapeutic interventions. The diversity and complexity of such a complex and highly dynamic systems pose many challenges in targeting PPIs by drug-like molecules with necessary selectivity and potency. Traditional and novel drug discovery strategies have provided tools for designing and assessing PPI inhibitors against infectious diseases.
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4
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Abstract
DNA contains information that must be safeguarded, but also accessed for transcription and replication. To perform replication, eukaryotic cells use the B-family DNA polymerase enzymes Polδ and Polɛ, which are optimized for accuracy, speed, and processivity. The molecular basis of these high-performance characteristics causes these replicative polymerases to fail at sites of DNA damage (lesions), which would lead to genomic instability and cell death. To avoid this, cells possess additional DNA polymerases such as the Y-family of polymerases and the B-family member Polζ that can replicate over sites of DNA damage in a process called translesion synthesis (TLS). While able to replicate over DNA lesions, the TLS polymerases exhibit low-fidelity on undamaged DNA and, consequently, must be prevented from replicating DNA under normal circumstances and recruited only when necessary. The replicative bypass of most types of DNA lesions requires the consecutive action of these specialized TLS polymerases assembled into a dynamic multiprotein complex called the Rev1/Polζ mutasome. To this end, posttranslational modifications and a network of protein-protein interactions mediated by accessory domains/subunits of the TLS polymerases control the assembly and rearrangements of the Rev1/Polζ mutasome and recruitment of TLS proteins to sites of DNA damage. This chapter focuses on the structures and interactions that control these processes underlying the function of the Rev1/Polζ mutasome, as well as the development of small molecule inhibitors of the Rev1/Polζ-dependent TLS holding promise as a potential anticancer therapy.
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Affiliation(s)
- Alessandro A Rizzo
- Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, CT, United States
| | - Dmitry M Korzhnev
- Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, CT, United States.
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5
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Atkinson SC, Dogovski C, Wood K, Griffin MDW, Gorman MA, Hor L, Reboul CF, Buckle AM, Wuttke J, Parker MW, Dobson RCJ, Perugini MA. Substrate Locking Promotes Dimer-Dimer Docking of an Enzyme Antibiotic Target. Structure 2018; 26:948-959.e5. [PMID: 29804823 DOI: 10.1016/j.str.2018.04.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Revised: 02/27/2018] [Accepted: 04/19/2018] [Indexed: 11/19/2022]
Abstract
Protein dynamics manifested through structural flexibility play a central role in the function of biological molecules. Here we explore the substrate-mediated change in protein flexibility of an antibiotic target enzyme, Clostridium botulinum dihydrodipicolinate synthase. We demonstrate that the substrate, pyruvate, stabilizes the more active dimer-of-dimers or tetrameric form. Surprisingly, there is little difference between the crystal structures of apo and substrate-bound enzyme, suggesting protein dynamics may be important. Neutron and small-angle X-ray scattering experiments were used to probe substrate-induced dynamics on the sub-second timescale, but no significant changes were observed. We therefore developed a simple technique, coined protein dynamics-mass spectrometry (ProD-MS), which enables measurement of time-dependent alkylation of cysteine residues. ProD-MS together with X-ray crystallography and analytical ultracentrifugation analyses indicates that pyruvate locks the conformation of the dimer that promotes docking to the more active tetrameric form, offering insight into ligand-mediated stabilization of multimeric enzymes.
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Affiliation(s)
- Sarah C Atkinson
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia; Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, 30 Flemington Road, University of Melbourne, Parkville, VIC 3010, Australia
| | - Con Dogovski
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, 30 Flemington Road, University of Melbourne, Parkville, VIC 3010, Australia
| | - Kathleen Wood
- Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW 2234, Australia
| | - Michael D W Griffin
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, 30 Flemington Road, University of Melbourne, Parkville, VIC 3010, Australia
| | - Michael A Gorman
- ACRF Rational Drug Discovery Centre, St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia
| | - Lilian Hor
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, 30 Flemington Road, University of Melbourne, Parkville, VIC 3010, Australia; Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC 3086, Australia; ARC Centre of Excellence in Advanced Molecular Imaging, La Trobe University, Melbourne, VIC 3086, Australia
| | - Cyril F Reboul
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Ashley M Buckle
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Joachim Wuttke
- Juelich Centre for Neutron Science (JCNS), at Heinz Maier-Leibnitz Zentrum (MLZ), Forschungszentrum Juelich GmbH, Lichtenstrasse 1, Garching 85 747, Germany
| | - Michael W Parker
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, 30 Flemington Road, University of Melbourne, Parkville, VIC 3010, Australia; ACRF Rational Drug Discovery Centre, St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia
| | - Renwick C J Dobson
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, 30 Flemington Road, University of Melbourne, Parkville, VIC 3010, Australia; Biomolecular Interaction Centre, School of Biological Sciences, University of Canterbury, Private Bag, Christchurch 4800, New Zealand
| | - Matthew A Perugini
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, 30 Flemington Road, University of Melbourne, Parkville, VIC 3010, Australia; Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC 3086, Australia.
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6
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Maffucci I, Contini A. Improved Computation of Protein–Protein Relative Binding Energies with the Nwat-MMGBSA Method. J Chem Inf Model 2016; 56:1692-704. [DOI: 10.1021/acs.jcim.6b00196] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Irene Maffucci
- Dipartimento di Scienze Farmaceutiche
− Sezione di Chimica Generale e Organica “Alessandro
Marchesini”, Università degli Studi di Milano, Via
Venezian, 21, 20133 Milano, Italy
| | - Alessandro Contini
- Dipartimento di Scienze Farmaceutiche
− Sezione di Chimica Generale e Organica “Alessandro
Marchesini”, Università degli Studi di Milano, Via
Venezian, 21, 20133 Milano, Italy
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7
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Beekman AM, O'Connell MA, Howell LA. Identification of Small-Molecule Inhibitors of the Antiapoptotic Protein Myeloid Cell Leukaemia-1 (Mcl-1). ChemMedChem 2016; 11:840-4. [PMID: 26616140 PMCID: PMC4848766 DOI: 10.1002/cmdc.201500488] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Indexed: 12/21/2022]
Abstract
Protein-protein interactions (PPIs) control many cellular processes in cancer and tumour growth. Of significant interest is the role PPIs play in regulating apoptosis. The overexpression of the antiapoptosis regulating Bcl-2 family of proteins is commonly observed in several cancers, leading to resistance towards both radiation and chemotherapies. From this family, myeloid cell leukemia-1 (Mcl-1) has proven the most difficult to target, and one of the leading causes of treatment resistance. Exploiting the selective PPI between the apoptosis-regulating protein Noxa and Mcl-1, utilising a fluorescence polarization assay, we have identified four small molecules with the ability to modulate Mcl-1. The identified compounds were computationally modelled and docked against the Mcl-1 binding interface to obtain structural information about their binding sites allowing for future analogue design. When examined for their activity towards pancreatic cell lines that overexpress Mcl-1 (MiaPaCa-2 and BxPC-3), the identified compounds demonstrated growth inhibition, suggesting effective Mcl-1 modulation.
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Affiliation(s)
- Andrew M Beekman
- School of Pharmacy, University of East Anglia, Norwich Research Park, Norwich, Norfolk, NR4 7TJ, UK
| | - Maria A O'Connell
- School of Pharmacy, University of East Anglia, Norwich Research Park, Norwich, Norfolk, NR4 7TJ, UK
| | - Lesley A Howell
- School of Pharmacy, University of East Anglia, Norwich Research Park, Norwich, Norfolk, NR4 7TJ, UK.
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8
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Corbi-Verge C, Kim PM. Motif mediated protein-protein interactions as drug targets. Cell Commun Signal 2016; 14:8. [PMID: 26936767 PMCID: PMC4776425 DOI: 10.1186/s12964-016-0131-4] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Accepted: 02/25/2016] [Indexed: 12/17/2022] Open
Abstract
Protein-protein interactions (PPI) are involved in virtually every cellular process and thus represent an attractive target for therapeutic interventions. A significant number of protein interactions are frequently formed between globular domains and short linear peptide motifs (DMI). Targeting these DMIs has proven challenging and classical approaches to inhibiting such interactions with small molecules have had limited success. However, recent new approaches have led to the discovery of potent inhibitors, some of them, such as Obatoclax, ABT-199, AEG-40826 and SAH-p53-8 are likely to become approved drugs. These novel inhibitors belong to a wide range of different molecule classes, ranging from small molecules to peptidomimetics and biologicals. This article reviews the main reasons for limited success in targeting PPIs, discusses how successful approaches overcome these obstacles to discovery promising inhibitors for human protein double minute 2 (HDM2), B-cell lymphoma 2 (Bcl-2), X-linked inhibitor of apoptosis protein (XIAP), and provides a summary of the promising approaches currently in development that indicate the future potential of PPI inhibitors in drug discovery.
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Affiliation(s)
- Carles Corbi-Verge
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON, M5S 3E1, Canada.
| | - Philip M Kim
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON, M5S 3E1, Canada.
- Department of Molecular Genetics, University of Toronto, Toronto, ON, M5S 3E1, Canada.
- Department of Computer Science, University of Toronto, Toronto, ON, M5S 3E1, Canada.
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9
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Peverelli MG, Soares da Costa TP, Kirby N, Perugini MA. Dimerization of Bacterial Diaminopimelate Decarboxylase Is Essential for Catalysis. J Biol Chem 2016; 291:9785-95. [PMID: 26921318 DOI: 10.1074/jbc.m115.696591] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Indexed: 11/06/2022] Open
Abstract
Diaminopimelate decarboxylase (DAPDC) catalyzes the final step in the diaminopimelate biosynthesis pathway of bacteria. The product of the reaction is the essential amino acid l-lysine, which is an important precursor for the synthesis of the peptidoglycan cell wall, housekeeping proteins, and virulence factors of bacteria. Accordingly, the enzyme is a promising antibacterial target. Previous structural studies demonstrate that DAPDC exists as monomers, dimers, and tetramers in the crystal state. However, the active oligomeric form has not yet been determined. We show using analytical ultracentrifugation, small angle x-ray scattering, and enzyme kinetic analyses in solution that the active form of DAPDC from Bacillus anthracis, Escherichia coli, Mycobacterium tuberculosis, and Vibrio cholerae is a dimer. The importance of dimerization was probed further by generating dimerization interface mutants (N381A and R385A) of V. cholerae DAPDC. Our studies indicate that N381A and R385A are significantly attenuated in catalytic activity, thus confirming that dimerization of DAPDC is essential for function. These findings provide scope for the development of new antibacterial agents that prevent DAPDC dimerization.
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Affiliation(s)
- Martin G Peverelli
- From the Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, the Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, Parkville, Victoria 3010, and
| | - Tatiana P Soares da Costa
- From the Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086
| | - Nigel Kirby
- the The Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168, Australia
| | - Matthew A Perugini
- From the Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, the Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, Parkville, Victoria 3010, and
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10
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Tan YS, Spring DR, Abell C, Verma CS. The Application of Ligand-Mapping Molecular Dynamics Simulations to the Rational Design of Peptidic Modulators of Protein-Protein Interactions. J Chem Theory Comput 2015; 11:3199-210. [PMID: 26575757 DOI: 10.1021/ct5010577] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A computational ligand-mapping approach to detect protein surface pockets that interact with hydrophobic moieties is presented. In this method, we incorporated benzene molecules into explicit solvent molecular dynamics simulations of various protein targets. The benzene molecules successfully identified the binding locations of hydrophobic hot-spot residues and all-hydrocarbon cross-links from known peptidic ligands. They also unveiled cryptic binding sites that are occluded by side chains and the protein backbone. Our results demonstrate that ligand-mapping molecular dynamics simulations hold immense promise to guide the rational design of peptidic modulators of protein-protein interactions, including that of stapled peptides, which show promise as an exciting new class of cell-penetrating therapeutic molecules.
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Affiliation(s)
- Yaw Sing Tan
- Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, United Kingdom.,Bioinformatics Institute (A*STAR) , 30 Biopolis Street, #07-01 Matrix, Singapore 138671
| | - David R Spring
- Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Chris Abell
- Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Chandra S Verma
- Bioinformatics Institute (A*STAR) , 30 Biopolis Street, #07-01 Matrix, Singapore 138671.,Department of Biological Sciences, National University of Singapore , 14 Science Drive 4, Singapore 117543.,School of Biological Sciences, Nanyang Technological University , 60 Nanyang Drive, Singapore 637551
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11
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Abstract
Protein-protein interactions regulate many important cellular processes, including carbohydrate and lipid metabolism, cell cycle and cell death regulation, protein and nucleic acid metabolism, signal transduction, and cellular architecture. A complete understanding of cellular function depends on full characterization of the complex network of cellular protein-protein interactions, including measurements of their kinetic and binding properties. Surface plasmon resonance (SPR) is one of the commonly used technologies for detailed and quantitative studies of protein-protein interactions and determination of their equilibrium and kinetic parameters. SPR provides excellent instrumentation for a label-free, real-time investigation of protein-protein interactions. This chapter details the experimental design and proper use of the instrumentation for a kinetic experiment. It will provide readers with basic theory, assay setup, and the proper way of reporting this type of results with practical tips useful for SPR-based studies. A generic protocol for immobilizing ligands using amino coupling chemistry, also useful if an antibody affinity capture approach is used, performing kinetic studies, and collecting and analyzing data is described.
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Affiliation(s)
- Zaneta Nikolovska-Coleska
- Department of Pathology, University of Michigan Medical School, 4510E MSRB I, 1150 West Medical Center Drive, Ann Arbor, MI, 48109, USA,
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12
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Atkinson SC, Hor L, Dogovski C, Dobson RCJ, Perugini MA. Identification of the bona fide DHDPS from a common plant pathogen. Proteins 2014; 82:1869-83. [PMID: 24677246 DOI: 10.1002/prot.24539] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2013] [Revised: 01/06/2014] [Accepted: 02/13/2014] [Indexed: 11/10/2022]
Abstract
Agrobacterium tumefaciens is a Gram-negative soil-borne bacterium that causes Crown Gall disease in many economically important crops. The absence of a suitable chemical treatment means there is a need to discover new anti-Crown Gall agents and also characterize bona fide drug targets. One such target is dihydrodipicolinate synthase (DHDPS), a homo-tetrameric enzyme that catalyzes the committed step in the metabolic pathway yielding meso-diaminopimelate and lysine. Interestingly, there are 10 putative DHDPS genes annotated in the A. tumefaciens genome, including three whose structures have recently been determined (PDB IDs: 3B4U, 2HMC, and 2R8W). However, we show using quantitative enzyme kinetic assays that nine of the 10 dapA gene products, including 3B4U, 2HMC, and 2R8W, lack DHDPS function in vitro. A sequence alignment showed that the product of the dapA7 gene contains all of the conserved residues known to be important for DHDPS catalysis and allostery. This gene was cloned and the recombinant product expressed and purified. Our studies show that the purified enzyme (i) possesses DHDPS enzyme activity, (ii) is allosterically inhibited by lysine, and (iii) adopts the canonical homo-tetrameric structure in both solution and the crystal state. This study describes for the first time the structure, function and allostery of the bona fide DHDPS from A. tumefaciens, which offers insight into the rational design of pesticide agents for combating Crown Gall disease.
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Affiliation(s)
- Sarah C Atkinson
- Department of Biochemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, 3086, Australia; Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Victoria, 3010, Australia
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13
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Ciglia E, Vergin J, Reimann S, Smits SHJ, Schmitt L, Groth G, Gohlke H. Resolving hot spots in the C-terminal dimerization domain that determine the stability of the molecular chaperone Hsp90. PLoS One 2014; 9:e96031. [PMID: 24760083 PMCID: PMC3997499 DOI: 10.1371/journal.pone.0096031] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Accepted: 04/02/2014] [Indexed: 12/24/2022] Open
Abstract
Human heat shock protein of 90 kDa (hHsp90) is a homodimer that has an essential role in facilitating malignant transformation at the molecular level. Inhibiting hHsp90 function is a validated approach for treating different types of tumors. Inhibiting the dimerization of hHsp90 via its C-terminal domain (CTD) should provide a novel way to therapeutically interfere with hHsp90 function. Here, we predicted hot spot residues that cluster in the CTD dimerization interface by a structural decomposition of the effective energy of binding computed by the MM-GBSA approach and confirmed these predictions using in silico alanine scanning with DrugScore(PPI). Mutation of these residues to alanine caused a significant decrease in the melting temperature according to differential scanning fluorimetry experiments, indicating a reduced stability of the mutant hHsp90 complexes. Size exclusion chromatography and multi-angle light scattering studies demonstrate that the reduced stability of the mutant hHsp90 correlates with a lower complex stoichiometry due to the disruption of the dimerization interface. These results suggest that the identified hot spot residues can be used as a pharmacophoric template for identifying and designing small-molecule inhibitors of hHsp90 dimerization.
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Affiliation(s)
- Emanuele Ciglia
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich-Heine-University, Düsseldorf, Germany
| | - Janina Vergin
- Institute for Biochemical Plant Physiology, Heinrich-Heine-University, Düsseldorf, Germany
| | - Sven Reimann
- Institute of Biochemistry, Heinrich-Heine-University, Düsseldorf, Germany
| | - Sander H. J. Smits
- Institute of Biochemistry, Heinrich-Heine-University, Düsseldorf, Germany
| | - Lutz Schmitt
- Institute of Biochemistry, Heinrich-Heine-University, Düsseldorf, Germany
| | - Georg Groth
- Institute for Biochemical Plant Physiology, Heinrich-Heine-University, Düsseldorf, Germany
| | - Holger Gohlke
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich-Heine-University, Düsseldorf, Germany
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14
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Spanier L, Ciglia E, Hansen FK, Kuna K, Frank W, Gohlke H, Kurz T. Design, synthesis, and conformational analysis of trispyrimidonamides as α-helix mimetics. J Org Chem 2014; 79:1582-93. [PMID: 24447208 DOI: 10.1021/jo402353z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The straightforward synthesis of trispyrimidonamides as a new class of α-helix mimetics is reported. Because of the versatility of our synthetic protocol, a variety of side chains including aliphatic, basic, aromatic, and heteroaromatic residues were included. A comprehensive conformational analysis revealed that in polar solvents a trimeric compound adopts conformations that can lead to i, i + 4, i + 8, or i, i + 8 patterns of side chain orientation. This suggests that trispyrimidonamides could be promising α-helix mimetics to target hot spots that are distributed over a wider angular range of an α-helix interface than in the classical i, i + 4, i + 7 case.
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Affiliation(s)
- Lukas Spanier
- Institut für Pharmazeutische und Medizinische Chemie, Heinrich-Heine-Universität Düsseldorf , Universitätsstr. 1, 40225 Düsseldorf, Germany
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15
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Dogovski C, Gorman MA, Ketaren NE, Praszkier J, Zammit LM, Mertens HD, Bryant G, Yang J, Griffin MDW, Pearce FG, Gerrard JA, Jameson GB, Parker MW, Robins-Browne RM, Perugini MA. From knock-out phenotype to three-dimensional structure of a promising antibiotic target from Streptococcus pneumoniae. PLoS One 2013; 8:e83419. [PMID: 24349508 PMCID: PMC3862839 DOI: 10.1371/journal.pone.0083419] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Accepted: 11/13/2013] [Indexed: 11/18/2022] Open
Abstract
Given the rise in drug-resistant Streptococcus pneumoniae, there is an urgent need to discover new antimicrobials targeting this pathogen and an equally urgent need to characterize new drug targets. A promising antibiotic target is dihydrodipicolinate synthase (DHDPS), which catalyzes the rate-limiting step in lysine biosynthesis. In this study, we firstly show by gene knock out studies that S. pneumoniae (sp) lacking the DHDPS gene is unable to grow unless supplemented with lysine-rich media. We subsequently set out to characterize the structure, function and stability of the enzyme drug target. Our studies show that sp-DHDPS is folded and active with a k(cat) = 22 s(-1), K(M)(PYR) = 2.55 ± 0.05 mM and K(M)(ASA) = 0.044 ± 0.003 mM. Thermal denaturation experiments demonstrate sp-DHDPS exhibits an apparent melting temperature (T(M)(app)) of 72 °C, which is significantly greater than Escherichia coli DHDPS (Ec-DHDPS) (T(M)(app) = 59 °C). Sedimentation studies show that sp-DHDPS exists in a dimer-tetramer equilibrium with a K(D)(4→2) = 1.7 nM, which is considerably tighter than its E. coli ortholog (K(D)(4→2) = 76 nM). To further characterize the structure of the enzyme and probe its enhanced stability, we solved the high resolution (1.9 Å) crystal structure of sp-DHDPS (PDB ID 3VFL). The enzyme is tetrameric in the crystal state, consistent with biophysical measurements in solution. Although the sp-DHDPS and Ec-DHDPS active sites are almost identical, the tetramerization interface of the s. pneumoniae enzyme is significantly different in composition and has greater buried surface area (800 Å(2)) compared to its E. coli counterpart (500 Å(2)). This larger interface area is consistent with our solution studies demonstrating that sp-DHDPS is considerably more thermally and thermodynamically stable than Ec-DHDPS. Our study describe for the first time the knock-out phenotype, solution properties, stability and crystal structure of DHDPS from S. pneumoniae, a promising antimicrobial target.
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Affiliation(s)
- Con Dogovski
- Department of Biochemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria, Australia
| | - Michael A. Gorman
- St Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia
| | - Natalia E. Ketaren
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria, Australia
| | - Judy Praszkier
- Department of Microbiology & Immunology, University of Melbourne, Victoria, Australia
| | - Leanne M. Zammit
- Department of Biochemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia
| | | | - Gary Bryant
- School of Applied Sciences, RMIT University, Melbourne, Victoria, Australia
| | - Ji Yang
- Department of Microbiology & Immunology, University of Melbourne, Victoria, Australia
| | - Michael D. W. Griffin
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria, Australia
| | - F. Grant Pearce
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
| | - Juliet A. Gerrard
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
- Callaghan Innovation, Lower Hutt, New Zealand
| | - Geoffrey B. Jameson
- Centre for Structural Biology, Institute of Fundamental Sciences, Massey University, Palmerston North, New Zealand
| | - Michael W. Parker
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria, Australia
- St Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia
| | - Roy M. Robins-Browne
- Department of Microbiology & Immunology, University of Melbourne, Victoria, Australia
| | - Matthew A. Perugini
- Department of Biochemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria, Australia
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16
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Identifying chemicals with potential therapy of HIV based on protein-protein and protein-chemical interaction network. PLoS One 2013; 8:e65207. [PMID: 23762317 PMCID: PMC3675210 DOI: 10.1371/journal.pone.0065207] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Accepted: 04/23/2013] [Indexed: 12/27/2022] Open
Abstract
Acquired immune deficiency syndrome (AIDS) is a severe infectious disease that causes a large number of deaths every year. Traditional anti-AIDS drugs directly targeting the HIV-1 encoded enzymes including reverse transcriptase (RT), protease (PR) and integrase (IN) usually suffer from drug resistance after a period of treatment and serious side effects. In recent years, the emergence of numerous useful information of protein-protein interactions (PPI) in the HIV life cycle and related inhibitors makes PPI a new way for antiviral drug intervention. In this study, we identified 26 core human proteins involved in PPI between HIV-1 and host, that have great potential for HIV therapy. In addition, 280 chemicals that interact with three HIV drugs targeting human proteins can also interact with these 26 core proteins. All these indicate that our method as presented in this paper is quite promising. The method may become a useful tool, or at least plays a complementary role to the existing method, for identifying novel anti-HIV drugs.
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17
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Hor L, Dobson RCJ, Downton MT, Wagner J, Hutton CA, Perugini MA. Dimerization of bacterial diaminopimelate epimerase is essential for catalysis. J Biol Chem 2013; 288:9238-48. [PMID: 23426375 DOI: 10.1074/jbc.m113.450148] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Diaminopimelate (DAP) epimerase is involved in the biosynthesis of meso-DAP and lysine, which are important precursors for the synthesis of peptidoglycan, housekeeping proteins, and virulence factors in bacteria. Accordingly, DAP epimerase is a promising antimicrobial target. Previous studies report that DAP epimerase exists as a monomeric enzyme. However, we show using analytical ultracentrifugation, X-ray crystallography, and enzyme kinetic analyses that DAP epimerase from Escherichia coli exists as a functional dimer in solution and the crystal state. Furthermore, the 2.0-Å X-ray crystal structure of the E. coli DAP epimerase dimer shows for the first time that the enzyme exists in an open, active conformation. The importance of dimerization was subsequently probed by using site-directed mutagenesis to generate a monomeric mutant (Y268A). Our studies show that Y268A is catalytically inactive, thus demonstrating that dimerization of DAP epimerase is essential for catalysis. Molecular dynamics simulations indicate that the DAP epimerase monomer is inherently more flexible than the dimer, suggesting that dimerization optimizes protein dynamics to support function. Our findings offer insight into the development of novel antimicrobial agents targeting the dimeric antibiotic target DAP epimerase.
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Affiliation(s)
- Lilian Hor
- Department of Biochemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
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18
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Török B, Sood A, Bag S, Tulsan R, Ghosh S, Borkin D, Kennedy AR, Melanson M, Madden R, Zhou W, Levine H, Török M. Diaryl hydrazones as multifunctional inhibitors of amyloid self-assembly. Biochemistry 2013; 52:1137-48. [PMID: 23346953 DOI: 10.1021/bi3012059] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The design and application of an effective, new class of multifunctional small molecule inhibitors of amyloid self-assembly are described. Several compounds based on the diaryl hydrazone scaffold were designed. Forty-four substituted derivatives of this core structure were synthesized using a variety of benzaldehydes and phenylhydrazines and characterized. The inhibitor candidates were evaluated in multiple assays, including the inhibition of amyloid β (Aβ) fibrillogenesis and oligomer formation and the reverse processes, the disassembly of preformed fibrils and oligomers. Because the structure of the hydrazone-based inhibitors mimics the redox features of the antioxidant resveratrol, the radical scavenging effect of the compounds was evaluated by colorimetric assays against 2,2-diphenyl-1-picrylhydrazyl and superoxide radicals. The hydrazone scaffold was active in all of the different assays. The structure-activity relationship revealed that the substituents on the aromatic rings had a considerable effect on the overall activity of the compounds. The inhibitors showed strong activity in fibrillogenesis inhibition and disassembly, and even greater potency in the inhibition of oligomer formation and oligomer disassembly. Supporting the quantitative fluorometric and colorimetric assays, size exclusion chromatographic studies indicated that the best compounds practically eliminated or substantially inhibited the formation of soluble, aggregated Aβ species, as well. Atomic force microscopy was also applied to monitor the morphology of Aβ deposits. The compounds also possessed the predicted antioxidant properties; approximately 30% of the synthesized compounds showed a radical scavenging effect equal to or better than that of resveratrol or ascorbic acid.
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Affiliation(s)
- Béla Török
- Department of Chemistry, University of Massachusetts Boston, 100 Morrissey Boulevard, Boston, MA 02125-3393, USA
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19
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Comparative structure and function analyses of native and his-tagged forms of dihydrodipicolinate reductase from methicillin-resistant Staphylococcus aureus. Protein Expr Purif 2012; 85:66-76. [DOI: 10.1016/j.pep.2012.06.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Revised: 06/25/2012] [Accepted: 06/27/2012] [Indexed: 11/22/2022]
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20
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Zuo Z, Gandhi NS, Arndt KM, Mancera RL. Free energy calculations of the interactions of c-Jun-based synthetic peptides with the c-Fos protein. Biopolymers 2012; 97:899-909. [DOI: 10.1002/bip.22099] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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21
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Battle CH, Jayawickramarajah J. Supramolecular Approaches for Inhibition of Protein-Protein and Protein-DNA Interactions. Supramol Chem 2012. [DOI: 10.1002/9780470661345.smc181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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22
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Silvian LF, Friedman JE, Strauch K, Cachero TG, Day ES, Qian F, Cunningham B, Fung A, Sun L, Shipps GW, Su L, Zheng Z, Kumaravel G, Whitty A. Small molecule inhibition of the TNF family cytokine CD40 ligand through a subunit fracture mechanism. ACS Chem Biol 2011; 6:636-47. [PMID: 21417339 PMCID: PMC3415792 DOI: 10.1021/cb2000346] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
BIO8898 is one of several synthetic organic molecules that have recently been reported to inhibit receptor binding and function of the constitutively trimeric tumor necrosis factor (TNF) family cytokine CD40 ligand (CD40L, aka CD154). Small molecule inhibitors of protein-protein interfaces are relatively rare, and their discovery is often very challenging. Therefore, to understand how BIO8898 achieves this feat, we characterized its mechanism of action using biochemical assays and X-ray crystallography. BIO8898 inhibited soluble CD40L binding to CD40-Ig with a potency of IC(50) = 25 μM and inhibited CD40L-dependent apoptosis in a cellular assay. A co-crystal structure of BIO8898 with CD40L revealed that one inhibitor molecule binds per protein trimer. Surprisingly, the compound binds not at the surface of the protein but by intercalating deeply between two subunits of the homotrimeric cytokine, disrupting a constitutive protein-protein interface and breaking the protein's 3-fold symmetry. The compound forms several hydrogen bonds with the protein, within an otherwise hydrophobic binding pocket. In addition to the translational splitting of the trimer, binding of BIO8898 was accompanied by additional local and longer-range conformational perturbations of the protein, both in the core and in a surface loop. Binding of BIO8898 is reversible, and the resulting complex is stable and does not lead to detectable dissociation of the protein trimer. Our results suggest that a set of core aromatic residues that are conserved across a subset of TNF family cytokines might represent a generic hot-spot for the induced-fit binding of trimer-disrupting small molecules.
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Affiliation(s)
- Laura F. Silvian
- Department of Drug Discovery, Biogen Idec, 12 Cambridge Center, Cambridge, Massachusetts 02142.
,To whom correspondence should be addressed: ,
| | - Jessica E. Friedman
- Department of Drug Discovery, Biogen Idec, 12 Cambridge Center, Cambridge, Massachusetts 02142.
| | - Kathy Strauch
- Department of Drug Discovery, Biogen Idec, 12 Cambridge Center, Cambridge, Massachusetts 02142.
| | - Teresa G. Cachero
- Department of Drug Discovery, Biogen Idec, 12 Cambridge Center, Cambridge, Massachusetts 02142.
| | - Eric S. Day
- Department of Drug Discovery, Biogen Idec, 12 Cambridge Center, Cambridge, Massachusetts 02142.
| | - Fang Qian
- Department of Drug Discovery, Biogen Idec, 12 Cambridge Center, Cambridge, Massachusetts 02142.
| | - Brian Cunningham
- Sunesis Pharmaceuticals, Incorporated, 341 Oyster Point Boulevard, South San Francisco, CA 94080.
| | - Amy Fung
- Sunesis Pharmaceuticals, Incorporated, 341 Oyster Point Boulevard, South San Francisco, CA 94080.
| | - Lihong Sun
- Department of Drug Discovery, Biogen Idec, 12 Cambridge Center, Cambridge, Massachusetts 02142.
| | - Gerald W. Shipps
- Neogenesis Pharmaceuticals Inc., 840 Memorial Dr., Cambridge, MA 02139
| | - Lihe Su
- Department of Drug Discovery, Biogen Idec, 12 Cambridge Center, Cambridge, Massachusetts 02142.
| | - Zhongli Zheng
- Department of Drug Discovery, Biogen Idec, 12 Cambridge Center, Cambridge, Massachusetts 02142.
| | | | - Adrian Whitty
- Boston University, Department of Chemistry, Metcalf Center for Science and Engineering, 590 Commonwealth Ave, Boston, MA 02215.
,To whom correspondence should be addressed: ,
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23
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Evans G, Schuldt L, Griffin MDW, Devenish SRA, Grant Pearce F, Perugini MA, Dobson RCJ, Jameson GB, Weiss MS, Gerrard JA. A tetrameric structure is not essential for activity in dihydrodipicolinate synthase (DHDPS) from Mycobacterium tuberculosis. Arch Biochem Biophys 2011; 512:154-9. [PMID: 21672512 DOI: 10.1016/j.abb.2011.05.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Revised: 05/19/2011] [Accepted: 05/20/2011] [Indexed: 11/19/2022]
Abstract
Dihydrodipicolinate synthase (DHDPS) is a validated antibiotic target for which a new approach to inhibitor design has been proposed: disrupting native tetramer formation by targeting the dimer-dimer interface. In this study, rational design afforded a variant of Mycobacterium tuberculosis, Mtb-DHDPS-A204R, with disrupted quaternary structure. X-ray crystallography (at a resolution of 2.1Å) revealed a dimeric protein with an identical fold and active-site structure to the tetrameric wild-type enzyme. Analytical ultracentrifugation confirmed the dimeric structure in solution, yet the dimeric mutant has similar activity to the wild-type enzyme. Although the affinity for both substrates was somewhat decreased, the high catalytic competency of the enzyme was surprising in the light of previous results showing that dimeric variants of the Escherichia coli and Bacillus anthracis DHDPS enzymes have dramatically reduced activity compared to their wild-type tetrameric counterparts. These results suggest that Mtb-DHDPS-A204R is similar to the natively dimeric enzyme from Staphylococcus aureus, and highlight our incomplete understanding of the role played by oligomerisation in relating protein structure and function.
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Affiliation(s)
- Genevieve Evans
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
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24
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Kim SE, Liu F, Im YJ, Stephen AG, Fivash MJ, Waheed AA, Freed EO, Fisher RJ, Hurley JH, Burke TR. Elucidation of New Binding Interactions with the Tumor Susceptibility Gene 101 (Tsg101) Protein Using Modified HIV-1 Gag-p6 Derived Peptide Ligands. ACS Med Chem Lett 2011; 2:337-341. [PMID: 21643473 DOI: 10.1021/ml1002579] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Targeting protein-protein interactions is gaining greater recognition as an attractive approach to therapeutic development. An example of this may be found with the human cellular protein encoded by the tumor susceptibility gene 101 (Tsg101), where interaction with the p6 C-terminal domain of the nascent viral Gag protein is required for HIV-1 particle budding and release. This association of Gag with Tsg101 is highly dependent on a "Pro-Thr-Ala-Pro" ("PTAP") peptide sequence within the p6 protein. Although p6-derived peptides offer potential starting points for developing Tsg101-binding inhibitors, the affinities of canonical peptides are outside the useful range (K(d) values greater than 50 μM). Reported herein are crystal structures of Tsg101 in complex with two structurally-modified PTAP-derived peptides. This data define new regions of ligand interaction not previously identified with canonical peptide sequences. This information could be highly useful in the design of Tsg101-binding antagonists.
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Affiliation(s)
- Sung-Eun Kim
- Chemical Biology Laboratory, Molecular, Discovery Program, CCR, NCI-Frederick, Frederick, Maryland 21702, United States
| | - Fa Liu
- Chemical Biology Laboratory, Molecular, Discovery Program, CCR, NCI-Frederick, Frederick, Maryland 21702, United States
| | | | | | - Matthew J. Fivash
- Data Management Systems, Inc., NCI-Frederick, Frederick, Maryland 21702, United States
| | - Abdul A. Waheed
- HIV Drug Resistance Program, CCR, NCI-Frederick, Frederick, Maryland 21702, United States
| | - Eric O. Freed
- HIV Drug Resistance Program, CCR, NCI-Frederick, Frederick, Maryland 21702, United States
| | | | | | - Terrence R. Burke
- Chemical Biology Laboratory, Molecular, Discovery Program, CCR, NCI-Frederick, Frederick, Maryland 21702, United States
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25
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Zuo Z, Gandhi NS, Mancera RL. Calculations of the Free Energy of Interaction of the c-Fos−c-Jun Coiled Coil: Effects of the Solvation Model and the Inclusion of Polarization Effects. J Chem Inf Model 2010; 50:2201-12. [DOI: 10.1021/ci100321h] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Zhili Zuo
- Curtin Health Innovation Research Institute, Western Australian Biomedical Research Institute, School of Biomedical Sciences and School of Pharmacy, Curtin University, GPO Box U1987, Perth WA 6845, Australia
| | - Neha S. Gandhi
- Curtin Health Innovation Research Institute, Western Australian Biomedical Research Institute, School of Biomedical Sciences and School of Pharmacy, Curtin University, GPO Box U1987, Perth WA 6845, Australia
| | - Ricardo L. Mancera
- Curtin Health Innovation Research Institute, Western Australian Biomedical Research Institute, School of Biomedical Sciences and School of Pharmacy, Curtin University, GPO Box U1987, Perth WA 6845, Australia
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26
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Xu Z, DiCesare JC, Baures PW. Parallel synthesis of an oligomeric imidazole-4,5-dicarboxamide library. ACTA ACUST UNITED AC 2010; 12:248-54. [PMID: 20170086 DOI: 10.1021/cc1000105] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A library of oligomeric compounds was synthesized based on the imidazole-4,5-dicarboxylic acid scaffold along with amino acid esters and chiral diamines derived from amino acids. The final compounds incorporate nonpolar amino acids (Leu, Phe, Trp), polar amino acids (Ser, Asp, Arg), and neutral amino acids (Gly, Ala), and were designed to be useful in screening for inhibitors of protein-protein interactions. Many of the protected and deprotected oligomers show evidence of conformational isomers persistent at room temperature in aqueous solution. A total of 317 final oligomers, out of 441 targeted compounds, were obtained in high analytical purity and of sufficient quantity to submit them for high-throughput screening as part of the NIH Roadmap.
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Affiliation(s)
- Zhigang Xu
- Department of Chemistry and Biochemistry, The University of Tulsa, Tulsa, Oklahoma 74104, USA
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27
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Sood A, Abid M, Hailemichael S, Foster M, Török B, Török M. Effect of chirality of small molecule organofluorine inhibitors of amyloid self-assembly on inhibitor potency. Bioorg Med Chem Lett 2009; 19:6931-4. [PMID: 19880318 PMCID: PMC2785120 DOI: 10.1016/j.bmcl.2009.10.066] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2009] [Revised: 10/14/2009] [Accepted: 10/15/2009] [Indexed: 12/31/2022]
Abstract
The effect of enantiomeric trifluoromethyl-indolyl-acetic acid ethyl esters on the fibrillogenesis of Alzheimer's amyloid beta (Abeta) peptide is described. These compounds have been previously identified as effective inhibitors of the Abeta self-assembly in their racemic form. Thioflavin-T Fluorescence Spectroscopy and Atomic Force Microscopy were applied to assess the potency of the chiral target compounds. Both enantiomers showed significant inhibition in the in vitro assays. The potency of the enantiomeric inhibitors appeared to be very similar to each other suggesting the lack of the stereospecific binding interactions between these small molecule inhibitors and the Abeta peptide.
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Affiliation(s)
- Abha Sood
- Department of Chemistry, University of Massachusetts Boston, 100 Morrissey Blvd. Boston, MA 02125-3393, USA
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28
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Devenish SR, Gerrard JA. The quaternary structure of Escherichia coli N-acetylneuraminate lyase is essential for functional expression. Biochem Biophys Res Commun 2009; 388:107-11. [DOI: 10.1016/j.bbrc.2009.07.128] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2009] [Accepted: 07/24/2009] [Indexed: 12/19/2022]
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29
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Targeting protein–protein interactions for therapeutic intervention: a challenge for the future. Future Med Chem 2009; 1:65-93. [DOI: 10.4155/fmc.09.12] [Citation(s) in RCA: 187] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Background: Over the last two decades, an increasing research effort in academia and industry has focused on the modulation (both inhibition and stabilization) of protein–protein interactions (PPIs) in order to develop novel therapeutic approaches and target-selective agents in drug discovery. Discussion: The diversity and complexity of highly dynamic systems such as PPIs present many challenges for the identification of drug-like molecules with the ability to modulate the PPI with the necessary selectivity and potency. In this review, a number of these strategies will be presented along with a critical overview of the challenges and potential solutions relating to the exploitation of PPIs as molecular targets. Conclusions: Both traditional drug discovery approaches and some more recently developed innovative strategies have already provided valuable tools for the discovery of PPI modulators, and a number of successful examples have highlighted the potential of targeting PPIs for therapeutic intervention, especially in the oncology area.
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30
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Devenish SRA, Huisman FHA, Parker EJ, Hadfield AT, Gerrard JA. Cloning and characterisation of dihydrodipicolinate synthase from the pathogen Neisseria meningitidis. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2009; 1794:1168-74. [PMID: 19236959 DOI: 10.1016/j.bbapap.2009.02.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2008] [Revised: 01/22/2009] [Accepted: 02/05/2009] [Indexed: 11/16/2022]
Abstract
Neisseria meningitidis is an obligate commensal bacterium of humans, and also an important human pathogen. To facilitate future drug studies, we report here the biochemical and structural characterisation of a key enzyme in (S)-lysine biosynthesis, dihydrodipicolinate synthase (DHDPS), from N. meningitidis (NmeDHDPS). X-ray crystallography revealed only minor structural differences between NmeDHDPS and the enzyme from E. coli at the active and allosteric effector sites. The catalytic capabilities of NmeDHDPS are similar to those of the enzyme from E. coli, but intriguingly NmeDHDPS is subject to substrate inhibition by high concentrations of the second substrate, (S)-aspartate semialdehyde, and is also significantly more sensitive to feedback inhibition by (S)-lysine. This heightened sensitivity to inhibition at both active and allosteric sites suggests that it may be possible to target DHDPS from N. meningitidis for antibiotic development.
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Affiliation(s)
- Sean R A Devenish
- School of Biological Sciences, University of Canterbury, Christchurch, New Zealand.
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31
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Devenish SRA, Gerrard JA. The role of quaternary structure in (β/α)8-barrel proteins: evolutionary happenstance or a higher level of structure-function relationships? Org Biomol Chem 2009; 7:833-9. [DOI: 10.1039/b818251p] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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32
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Abstract
Retroviral replication hinges on the formation of the provirus, the integrated product of the linear DNA that is made during reverse transcription. Integration is catalyzed by the viral recombinase integrase, yet a number of studies indicate that other viral or cellular proteins play important cofactor roles during HIV-1 integration. Some of these factors bind directly to integrase, whereas others gain access to the integration machinery by binding to the DNA or other viral proteins. This article reviews recent advances on the roles of cellular proteins in HIV-1 integration. As a number of studies have highlighted a particularly important role for the integrase interactor lens epithelium-derived growth factor (LEDGF), much of the focus will be on its mechanism of action and the potential to develop inhibitors of this crucial virus–host interaction.
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Affiliation(s)
- Alan Engelman
- Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute and Division of AIDS, Harvard Medical School, Boston, MA 02115, USA
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