1
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Kim S, Yoon KA, Cho S, Lee SH. Molecular and kinetic characterization of two acetylcholinesterases with particular focus on the roles of two amino acid substitutions (Y390N and F392W) in Bemisia tabaci. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2022; 182:105039. [PMID: 35249657 DOI: 10.1016/j.pestbp.2022.105039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 01/11/2022] [Accepted: 01/12/2022] [Indexed: 06/14/2023]
Abstract
Two acetylcholinesterases (AChEs) are present in Bemisia tabaci (BtAChE1 and BtAChE2). A conserved AChE mutation conferring organophosphate (OP) resistance (F392W in BtAChE1) is saturated in field populations despite its potential fitness cost, and a highly conserved amino acid residue forming the backdoor of AChE is substituted with a unique amino acid (Y390N in BtAChE1) in B. tabaci. Thus, the roles and relationships of the two amino acid substitutions in the evolutionary adaptation of B. tabaci remain to be elucidated, and little information is available on the catalytic and molecular properties of BtAChE1 and BtAChE2. To determine which AChE is a more relevant target of OPs and carbamates, the molecular and kinetic properties of BtAChE1 and BtAChE2 were investigated. Both BtAChE1 and BtAChE2 were exclusively expressed in head and thorax but not in abdomen, bound to the membrane via GPI anchoring, and present as dimeric forms. Soluble monomeric form was detected only in BtAChE2. The catalytic activity of baculovirus-expressed BtAChE1 was 19.5-fold higher than that of BtAChE2. The inhibition assay revealed that the F392W mutation in BtAChE1 enhanced resistance to OPs. The artificial substitution of N390 (wild form) to Y (putative ancient form) led to reduced catalytic efficiency and increased inhibition by glycoalkaloids, suggesting that the Y390N substitution in BtAChE1 may have been required for Solanaceae host adaptation. BtAChE1 was proven to function as a main catalytic enzyme for ACh hydrolysis, thus being the main target of OPs and carbamates.
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Affiliation(s)
- Sanghyeon Kim
- Research Institute of Agriculture and Life Sciences, Seoul National University, 1, Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Kyungjae Andrew Yoon
- Research Institute of Agriculture and Life Sciences, Seoul National University, 1, Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - SuSie Cho
- Entomology Program, Department of Agricultural Biotechnology, Seoul National University, 1, Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Si Hyeock Lee
- Entomology Program, Department of Agricultural Biotechnology, Seoul National University, 1, Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea; Research Institute of Agriculture and Life Sciences, Seoul National University, 1, Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea.
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2
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Bagri K, Kumar A, Manisha, Kumar P. Computational Studies on Acetylcholinesterase Inhibitors: From Biochemistry to Chemistry. Mini Rev Med Chem 2021; 20:1403-1435. [PMID: 31884928 DOI: 10.2174/1389557520666191224144346] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 10/23/2019] [Accepted: 10/28/2019] [Indexed: 11/22/2022]
Abstract
Acetylcholinesterase inhibitors are the most promising therapeutics for Alzheimer's disease treatment as these prevent the loss of acetylcholine and slows the progression of the disease. The drugs approved for the management of Alzheimer's disease by the FDA are acetylcholinesterase inhibitors but are associated with side effects. Consistent and stringent efforts by the researchers with the help of computational methods opened new ways of developing novel molecules with good acetylcholinesterase inhibitory activity. In this manuscript, we reviewed the studies that identified the essential structural features of acetylcholinesterase inhibitors at the molecular level as well as the techniques like molecular docking, molecular dynamics, quantitative structure-activity relationship, virtual screening, and pharmacophore modelling that were used in designing these inhibitors.
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Affiliation(s)
- Kiran Bagri
- Department of Pharmaceutical Sciences, Guru Jambheshwar University of Science & Technology, Hisar 125001, India
| | - Ashwani Kumar
- Department of Pharmaceutical Sciences, Guru Jambheshwar University of Science & Technology, Hisar 125001, India
| | - Manisha
- Department of Pharmaceutical Sciences, Guru Jambheshwar University of Science & Technology, Hisar 125001, India
| | - Parvin Kumar
- Department of Chemistry, Kurukshetra University, Kurukshetra, India
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3
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De Boer D, Nguyen N, Mao J, Moore J, Sorin EJ. A Comprehensive Review of Cholinesterase Modeling and Simulation. Biomolecules 2021; 11:580. [PMID: 33920972 PMCID: PMC8071298 DOI: 10.3390/biom11040580] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 04/08/2021] [Accepted: 04/11/2021] [Indexed: 01/18/2023] Open
Abstract
The present article reviews published efforts to study acetylcholinesterase and butyrylcholinesterase structure and function using computer-based modeling and simulation techniques. Structures and models of both enzymes from various organisms, including rays, mice, and humans, are discussed to highlight key structural similarities in the active site gorges of the two enzymes, such as flexibility, binding site location, and function, as well as differences, such as gorge volume and binding site residue composition. Catalytic studies are also described, with an emphasis on the mechanism of acetylcholine hydrolysis by each enzyme and novel mutants that increase catalytic efficiency. The inhibitory activities of myriad compounds have been computationally assessed, primarily through Monte Carlo-based docking calculations and molecular dynamics simulations. Pharmaceutical compounds examined herein include FDA-approved therapeutics and their derivatives, as well as several other prescription drug derivatives. Cholinesterase interactions with both narcotics and organophosphate compounds are discussed, with the latter focusing primarily on molecular recognition studies of potential therapeutic value and on improving our understanding of the reactivation of cholinesterases that are bound to toxins. This review also explores the inhibitory properties of several other organic and biological moieties, as well as advancements in virtual screening methodologies with respect to these enzymes.
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Affiliation(s)
- Danna De Boer
- Department of Chemistry & Biochemistry, California State University, Long Beach, CA 90840, USA;
| | - Nguyet Nguyen
- Department of Chemical Engineering, California State University, Long Beach, CA 90840, USA; (N.N.); (J.M.)
| | - Jia Mao
- Department of Chemical Engineering, California State University, Long Beach, CA 90840, USA; (N.N.); (J.M.)
| | - Jessica Moore
- Department of Biomedical Engineering, California State University, Long Beach, CA 90840, USA;
| | - Eric J. Sorin
- Department of Chemistry & Biochemistry, California State University, Long Beach, CA 90840, USA;
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4
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Computational studies on cholinesterases: Strengthening our understanding of the integration of structure, dynamics and function. Neuropharmacology 2020; 179:108265. [DOI: 10.1016/j.neuropharm.2020.108265] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 05/21/2020] [Accepted: 07/27/2020] [Indexed: 12/17/2022]
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5
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Nachon F, Rosenberry TL, Silman I, Sussman JL. A Second Look at the Crystal Structures of Drosophila melanogaster Acetylcholinesterase in Complex with Tacrine Derivatives Provides Insights Concerning Catalytic Intermediates and the Design of Specific Insecticides. Molecules 2020; 25:molecules25051198. [PMID: 32155891 PMCID: PMC7179448 DOI: 10.3390/molecules25051198] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Revised: 03/03/2020] [Accepted: 03/04/2020] [Indexed: 11/16/2022] Open
Abstract
Over recent decades, crystallographic software for data processing and structure refinement has improved dramatically, resulting in more accurate and detailed crystal structures. It is, therefore, sometimes valuable to have a second look at "old" diffraction data, especially when earlier interpretation of the electron density maps was rather difficult. Here, we present updated crystal structures of Drosophila melanogaster acetylcholinesterase (DmAChE) originally published in [Harel et al., Prot Sci (2000) 9:1063-1072], which reveal features previously unnoticed. Thus, previously unmodeled density in the native active site can be interpreted as stable acetylation of the catalytic serine. Similarly, a strong density in the DmAChE/ZA complex originally attributed to a sulfate ion is better interpreted as a small molecule that is covalently bound. This small molecule can be modeled as either a propionate or a glycinate. The complex is reminiscent of the carboxylate butyrylcholinesterase complexes observed in crystal structures of human butyrylcholinesterases from various sources, and demonstrates the remarkable ability of cholinesterases to stabilize covalent complexes with carboxylates. A very strong peak of density (10 σ) at covalent distance from the Cβ of the catalytic serine is present in the DmAChE/ZAI complex. This can be undoubtedly attributed to an iodine atom, suggesting an unanticipated iodo/hydroxyl exchange between Ser238 and the inhibitor, possibly driven by the intense X-ray irradiation. Finally, the binding of tacrine-derived inhibitors, such as ZA (1DX4) or the iodinated analog, ZAI (1QON) results in the appearance of an open channel that connects the base of the active-site gorge to the solvent. This channel, which arises due to the absence of the conserved tyrosine present in vertebrate cholinesterases, could be exploited to design inhibitors specific to insect cholinesterases. The present study demonstrates that updated processing of older diffraction images, and the re-refinement of older diffraction data, can produce valuable information that could not be detected in the original analysis, and strongly supports the preservation of the diffraction images in public data banks.
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Affiliation(s)
- Florian Nachon
- Département de Toxicologie et Risques Chimiques, Institut de Recherche Biomédicale des Armées, 91220 Brétigny-sur-Orge, France
- Correspondence: ; Tel.: +33-178-65-1877
| | - Terrone L. Rosenberry
- Departments of Neuroscience and Pharmacology, Mayo Clinic College of Medicine, Jacksonville, FL 32224, USA;
| | - Israel Silman
- Department of Neurobiology, Weizmann Institute of Science, 7610001 Rehovot, Israel;
| | - Joel L. Sussman
- Department of Structural Biology, Weizmann Institute of Science, 7610001 Rehovot, Israel;
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6
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Bourne Y, Marchot P. Hot Spots for Protein Partnerships at the Surface of Cholinesterases and Related α/β Hydrolase Fold Proteins or Domains-A Structural Perspective. Molecules 2017; 23:molecules23010035. [PMID: 29295471 PMCID: PMC5943944 DOI: 10.3390/molecules23010035] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 12/21/2017] [Accepted: 12/21/2017] [Indexed: 12/12/2022] Open
Abstract
The hydrolytic enzymes acetyl- and butyryl-cholinesterase, the cell adhesion molecules neuroligins, and the hormonogenic macromolecule thyroglobulin are a few of the many members of the α/β hydrolase fold superfamily of proteins. Despite their distinctive functions, their canonical subunits, with a molecular surface area of ~20,000 Å2, they share binding patches and determinants for forming homodimers and for accommodating structural subunits or protein partners. Several of these surface regions of high functional relevance have been mapped through structural or mutational studies, while others have been proposed based on biochemical data or molecular docking studies. Here, we review these binding interfaces and emphasize their specificity versus potentially multifunctional character.
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Affiliation(s)
- Yves Bourne
- Centre National de la Recherche Scientifique, Aix-Marseille Université, "Architecture et Fonction des Macromolécules Biologiques" Laboratory, 13288 Marseille, France.
| | - Pascale Marchot
- Centre National de la Recherche Scientifique, Aix-Marseille Université, "Architecture et Fonction des Macromolécules Biologiques" Laboratory, 13288 Marseille, France.
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7
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Cheung J, Mahmood A, Kalathur R, Liu L, Carlier PR. Structure of the G119S Mutant Acetylcholinesterase of the Malaria Vector Anopheles gambiae Reveals Basis of Insecticide Resistance. Structure 2017; 26:130-136.e2. [PMID: 29276037 DOI: 10.1016/j.str.2017.11.021] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Revised: 11/01/2017] [Accepted: 11/27/2017] [Indexed: 10/18/2022]
Abstract
Malaria is a devastating disease in sub-Saharan Africa and is transmitted by the mosquito Anopheles gambiae. While indoor residual spraying of anticholinesterase insecticides has been useful in controlling the spread of malaria, widespread application of these compounds has led to the rise of an insecticide-resistant mosquito strain that harbors a G119S mutation in the nervous system target enzyme acetylcholinesterase. We demonstrate the atomic basis of insecticide resistance through structure determination of the G119S mutant acetylcholinesterase of An. gambiae in the ligand-free state and bound to a potent difluoromethyl ketone inhibitor. These structures reveal specific features within the active-site gorge distinct from human acetylcholinesterase, including an open channel at the base of the gorge, and provide a means for improving species selectivity in the rational design of improved insecticides for malaria vector control.
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Affiliation(s)
- Jonah Cheung
- New York Structural Biology Center, 89 Convent Avenue, New York, NY 10027, USA.
| | - Arshad Mahmood
- New York Structural Biology Center, 89 Convent Avenue, New York, NY 10027, USA
| | - Ravi Kalathur
- New York Structural Biology Center, 89 Convent Avenue, New York, NY 10027, USA
| | - Lixuan Liu
- Department of Chemistry, Virginia Tech, Blacksburg, VA 24061, USA
| | - Paul R Carlier
- Department of Chemistry, Virginia Tech, Blacksburg, VA 24061, USA
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8
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Xu Y, Cheng S, Sussman JL, Silman I, Jiang H. Computational Studies on Acetylcholinesterases. Molecules 2017; 22:molecules22081324. [PMID: 28796192 PMCID: PMC6152020 DOI: 10.3390/molecules22081324] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 08/07/2017] [Accepted: 08/07/2017] [Indexed: 01/18/2023] Open
Abstract
Functions of biomolecules, in particular enzymes, are usually modulated by structural fluctuations. This is especially the case in a gated diffusion-controlled reaction catalyzed by an enzyme such as acetylcholinesterase. The catalytic triad of acetylcholinesterase is located at the bottom of a long and narrow gorge, but it catalyzes the extremely rapid hydrolysis of the neurotransmitter, acetylcholine, with a reaction rate close to the diffusion-controlled limit. Computational modeling and simulation have produced considerable advances in exploring the dynamical and conformational properties of biomolecules, not only aiding in interpreting the experimental data, but also providing insights into the internal motions of the biomolecule at the atomic level. Given the remarkably high catalytic efficiency and the importance of acetylcholinesterase in drug development, great efforts have been made to understand the dynamics associated with its functions by use of various computational methods. Here, we present a comprehensive overview of recent computational studies on acetylcholinesterase, expanding our views of the enzyme from a microstate of a single structure to conformational ensembles, strengthening our understanding of the integration of structure, dynamics and function associated with the enzyme, and promoting the structure-based and/or mechanism-based design of new inhibitors for it.
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Affiliation(s)
- Yechun Xu
- CAS Key Laboratory of Receptor Research, Drug Discovery and Design Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences (CAS), Shanghai 201203, China.
| | - Shanmei Cheng
- CAS Key Laboratory of Receptor Research, Drug Discovery and Design Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences (CAS), Shanghai 201203, China.
| | - Joel L Sussman
- Israel Structural Proteomics Center, Weizmann Institute of Science, Rehovot 76100, Israel.
- Department of Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel.
| | - Israel Silman
- Department of Neurobiology, Weizmann Institute of Science, Rehovot 76100, Israel.
| | - Hualiang Jiang
- CAS Key Laboratory of Receptor Research, Drug Discovery and Design Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences (CAS), Shanghai 201203, China.
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9
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Silman I, Sussman JL. Recent developments in structural studies on acetylcholinesterase. J Neurochem 2017; 142 Suppl 2:19-25. [PMID: 28503857 DOI: 10.1111/jnc.13992] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This review focuses on several recent developments concerning structure-function relationships in vertebrate acetylcholinesterase. These include studies on high-resolution structures of human acetylcholinesterase and its complexes; the first crystal structure of a snake venom acetylcholinesterase, in which open and closed states of the 'back door' are visualized; a powerful algorithm for redesigning proteins for enhanced expression in prokaryotic systems, as applied to human acetylcholinesterase, which has hitherto been an intractable target; in situ implementation of 'click chemistry' in crystalline acetylcholinesterase, which yields novel insights into the steric and dynamic changes involved in the reaction within the active-site gorge; and a study that demonstrates the effect of crystallization conditions on ligand alignment within a protein complex, in this case the methylene blue-Torpedo californica acetylcholinesterase complex, which highlights the relevance of the precipitant employed to structure-based drug design. This is an article for the special issue XVth International Symposium on Cholinergic Mechanisms.
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Affiliation(s)
- Israel Silman
- Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel
| | - Joel L Sussman
- Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel
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10
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Cha DJ, Lee SH. Evolutionary origin and status of two insect acetylcholinesterases and their structural conservation and differentiation. Evol Dev 2015; 17:109-19. [DOI: 10.1111/ede.12111] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Deok Jea Cha
- Department of Agricultural Biotechnology; Seoul National University; Gwanakno; Gwanakgu Seoul 151-742 Republic of Korea
| | - Si Hyeock Lee
- Department of Agricultural Biotechnology; Seoul National University; Gwanakno; Gwanakgu Seoul 151-742 Republic of Korea
- Research Institute for Agriculture and Life Science; Seoul National University; Seoul 151-742 Republic of Korea
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11
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Bourne Y, Renault L, Marchot P. Crystal structure of snake venom acetylcholinesterase in complex with inhibitory antibody fragment Fab410 bound at the peripheral site: evidence for open and closed states of a back door channel. J Biol Chem 2014; 290:1522-35. [PMID: 25411244 DOI: 10.1074/jbc.m114.603902] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The acetylcholinesterase found in the venom of Bungarus fasciatus (BfAChE) is produced as a soluble, non-amphiphilic monomer with a canonical catalytic domain but a distinct C terminus compared with the other vertebrate enzymes. Moreover, the peripheral anionic site of BfAChE, a surface site located at the active site gorge entrance, bears two substitutions altering sensitivity to cationic inhibitors. Antibody Elec410, generated against Electrophorus electricus acetylcholinesterase (EeAChE), inhibits EeAChE and BfAChE by binding to their peripheral sites. However, both complexes retain significant residual catalytic activity, suggesting incomplete gorge occlusion by bound antibody and/or high frequency back door opening. To explore a novel acetylcholinesterase species, ascertain the molecular bases of inhibition by Elec410, and document the determinants and mechanisms for back door opening, we solved a 2.7-Å resolution crystal structure of natural BfAChE in complex with antibody fragment Fab410. Crystalline BfAChE forms the canonical dimer found in all acetylcholinesterase structures. Equally represented open and closed states of a back door channel, associated with alternate positions of a tyrosine phenol ring at the active site base, coexist in each subunit. At the BfAChE molecular surface, Fab410 is seated on the long Ω-loop between two N-glycan chains and partially occludes the gorge entrance, a position that fully reflects the available mutagenesis and biochemical data. Experimentally based flexible molecular docking supports a similar Fab410 binding mode onto the EeAChE antigen. These data document the molecular and dynamic peculiarities of BfAChE with high frequency back door opening, and the mode of action of Elec410 as one of the largest peptidic inhibitors targeting the acetylcholinesterase peripheral site.
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Affiliation(s)
- Yves Bourne
- From Aix-Marseille Université, Architecture et Fonction des Macromolécules Biologiques, campus Luminy, 13228 Marseille cedex 09, France, CNRS, Architecture et Fonction des Macromolécules Biologiques, campus Luminy, 13228 Marseille cedex 09, France, and
| | - Ludovic Renault
- CNRS/Aix-Marseille Université, Ingénierie des Protéines, Faculté de Médecine-Secteur Nord, 13344 Marseille cedex 15, France
| | - Pascale Marchot
- From Aix-Marseille Université, Architecture et Fonction des Macromolécules Biologiques, campus Luminy, 13228 Marseille cedex 09, France, CNRS, Architecture et Fonction des Macromolécules Biologiques, campus Luminy, 13228 Marseille cedex 09, France, and CNRS/Aix-Marseille Université, Ingénierie des Protéines, Faculté de Médecine-Secteur Nord, 13344 Marseille cedex 15, France
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12
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Bourne Y, Renault L, Essono S, Mondielli G, Lamourette P, Boquet D, Grassi J, Marchot P. Molecular characterization of monoclonal antibodies that inhibit acetylcholinesterase by targeting the peripheral site and backdoor region. PLoS One 2013; 8:e77226. [PMID: 24146971 PMCID: PMC3795623 DOI: 10.1371/journal.pone.0077226] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Accepted: 09/02/2013] [Indexed: 11/19/2022] Open
Abstract
The inhibition properties and target sites of monoclonal antibodies (mAbs) Elec403, Elec408 and Elec410, generated against Electrophorus electricus acetylcholinesterase (AChE), have been defined previously using biochemical and mutagenesis approaches. Elec403 and Elec410, which bind competitively with each other and with the peptidic toxin inhibitor fasciculin, are directed toward distinctive albeit overlapping epitopes located at the AChE peripheral anionic site, which surrounds the entrance of the active site gorge. Elec408, which is not competitive with the other two mAbs nor fasciculin, targets a second epitope located in the backdoor region, distant from the gorge entrance. To characterize the molecular determinants dictating their binding site specificity, we cloned and sequenced the mAbs; generated antigen-binding fragments (Fab) retaining the parental inhibition properties; and explored their structure-function relationships using complementary x-ray crystallography, homology modeling and flexible docking approaches. Hypermutation of one Elec403 complementarity-determining region suggests occurrence of antigen-driven selection towards recognition of the AChE peripheral site. Comparative analysis of the 1.9Å-resolution structure of Fab408 and of theoretical models of its Fab403 and Fab410 congeners evidences distinctive surface topographies and anisotropic repartitions of charges, consistent with their respective target sites and inhibition properties. Finally, a validated, data-driven docking model of the Fab403-AChE complex suggests a mode of binding at the PAS that fully correlates with the functional data. This comprehensive study documents the molecular peculiarities of Fab403 and Fab410, as the largest peptidic inhibitors directed towards the peripheral site, and those of Fab408, as the first inhibitor directed toward the backdoor region of an AChE and a unique template for the design of new, specific modulators of AChE catalysis.
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Affiliation(s)
- Yves Bourne
- Architecture et Fonction des Macromolécules Biologiques (AFMB), CNRS/Aix-Marseille Université, Campus Luminy, Marseille, France
| | - Ludovic Renault
- Ingénierie des Protéines, CNRS/Aix-Marseille Université, Faculté de Médecine - Secteur Nord, Marseille, France
| | - Sosthène Essono
- CEA, iBiTecS, Service de Pharmacologie et Immunologie (SPI), Laboratoire d’Etude et de Recherche en Immunoanalyse (LERI), Gif-sur-Yvette, France
| | - Grégoire Mondielli
- Centre de Recherche en Neurobiologie-Neurophysiologie de Marseille (CRN2M), CNRS/Aix-Marseille Université, Faculté de Médecine - Secteur Nord, Marseille, France
| | - Patricia Lamourette
- CEA, iBiTecS, Service de Pharmacologie et Immunologie (SPI), Laboratoire d’Etude et de Recherche en Immunoanalyse (LERI), Gif-sur-Yvette, France
| | - Didier Boquet
- CEA, iBiTecS, Service de Pharmacologie et Immunologie (SPI), Laboratoire d’Ingénierie des Anticorps pour la Santé (LIAS), Gif-sur-Yvette, France
| | - Jacques Grassi
- CEA, iBiTecS, Service de Pharmacologie et Immunologie (SPI), Laboratoire d’Etude et de Recherche en Immunoanalyse (LERI), Gif-sur-Yvette, France
| | - Pascale Marchot
- Architecture et Fonction des Macromolécules Biologiques (AFMB), CNRS/Aix-Marseille Université, Campus Luminy, Marseille, France
- Ingénierie des Protéines, CNRS/Aix-Marseille Université, Faculté de Médecine - Secteur Nord, Marseille, France
- Centre de Recherche en Neurobiologie-Neurophysiologie de Marseille (CRN2M), CNRS/Aix-Marseille Université, Faculté de Médecine - Secteur Nord, Marseille, France
- * E-mail:
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Crystal structures of human cholinesterases in complex with huprine W and tacrine: elements of specificity for anti-Alzheimer's drugs targeting acetyl- and butyryl-cholinesterase. Biochem J 2013; 453:393-9. [PMID: 23679855 DOI: 10.1042/bj20130013] [Citation(s) in RCA: 294] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The multifunctional nature of Alzheimer's disease calls for MTDLs (multitarget-directed ligands) to act on different components of the pathology, like the cholinergic dysfunction and amyloid aggregation. Such MTDLs are usually on the basis of cholinesterase inhibitors (e.g. tacrine or huprine) coupled with another active molecule aimed at a different target. To aid in the design of these MTDLs, we report the crystal structures of hAChE (human acetylcholinesterase) in complex with FAS-2 (fasciculin 2) and a hydroxylated derivative of huprine (huprine W), and of hBChE (human butyrylcholinesterase) in complex with tacrine. Huprine W in hAChE and tacrine in hBChE reside in strikingly similar positions highlighting the conservation of key interactions, namely, π-π/cation-π interactions with Trp86 (Trp82), and hydrogen bonding with the main chain carbonyl of the catalytic histidine residue. Huprine W forms additional interactions with hAChE, which explains its superior affinity: the isoquinoline moiety is associated with a group of aromatic residues (Tyr337, Phe338 and Phe295 not present in hBChE) in addition to Trp86; the hydroxyl group is hydrogen bonded to both the catalytic serine residue and residues in the oxyanion hole; and the chlorine substituent is nested in a hydrophobic pocket interacting strongly with Trp439. There is no pocket in hBChE that is able to accommodate the chlorine substituent.
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Genome organization, phylogenies, expression patterns, and three-dimensional protein models of two acetylcholinesterase genes from the red flour beetle. PLoS One 2012; 7:e32288. [PMID: 22359679 PMCID: PMC3281121 DOI: 10.1371/journal.pone.0032288] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2011] [Accepted: 01/26/2012] [Indexed: 11/19/2022] Open
Abstract
Since the report of a paralogous acetylcholinesterase (AChE, EC3.1.1.7) gene in the greenbug (Schizaphis graminum) in 2002, two different AChE genes (Ace1 and Ace2) have been identified in each of at least 27 insect species. However, the gene models of Ace1 and Ace2, and their molecular properties have not yet been comprehensively analyzed in any insect species. In this study, we sequenced the full-length cDNAs, computationally predicted the corresponding three-dimensional protein models, and profiled developmental stage and tissue-specific expression patterns of two Ace genes from the red flour beetle (Tribolium castaneum; TcAce1 and TcAce2), a globally distributed major pest of stored grain products and an emerging model organism. TcAce1 and TcAce2 encode 648 and 604 amino acid residues, respectively, and have conserved motifs including a choline-binding site, a catalytic triad, and an acyl pocket. Phylogenetic analysis show that both TcAce genes are grouped into two insect Ace clusters and TcAce1 is completely diverged from TcAce2, suggesting that these two genes evolve from their corresponding Ace gene lineages in insect species. In addition, TcAce1 is located on chromosome 5, whereas TcAce2 is located on chromosome 2. Reverse transcription polymerase chain reaction (PCR) and quantitative real-time PCR analyses indicate that both genes are virtually transcribed in all the developmental stages and predominately expressed in the insect brain. Our computational analyses suggest that the TcAce1 protein is a robust acetylcholine (ACh) hydrolase and has susceptibility to sulfhydryl agents whereas the TcAce2 protein is not a catalytically efficient ACh hydrolase.
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On the reducible character of Haldane-Radić enzyme kinetics to conventional and logistic Michaelis-Menten models. Molecules 2011; 16:3128-45. [PMID: 21490560 PMCID: PMC6260611 DOI: 10.3390/molecules16043128] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Revised: 04/13/2011] [Accepted: 04/13/2011] [Indexed: 11/30/2022] Open
Abstract
The conceptual and practical issues regarding the reduction of the Haldane-Radić enzymic mechanism, specific for cholinesterase kinetics, to the consecrated or logistically modified Michaelis-Menten kinetics, specific for some mutant enzymes, are here clarified as due to the limited initial substrate concentration, through detailed initial rate and progress curve analysis, even when other classical conditions for such equivalence are not entirely fulfilled.
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16
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Mining electron density for functionally relevant protein polysterism in crystal structures. Cell Mol Life Sci 2010; 68:1829-41. [PMID: 21190057 PMCID: PMC3092063 DOI: 10.1007/s00018-010-0611-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2010] [Revised: 11/18/2010] [Accepted: 12/09/2010] [Indexed: 11/26/2022]
Abstract
This review focuses on conceptual and methodological advances in our understanding and characterization of the conformational heterogeneity of proteins. Focusing on X-ray crystallography, we describe how polysterism, the interconversion of pre-existing conformational substates, has traditionally been analyzed by comparing independent crystal structures or multiple chains within a single crystal asymmetric unit. In contrast, recent studies have focused on mining electron density maps to reveal previously ‘hidden’ minor conformational substates. Functional tests of the importance of minor states suggest that evolutionary selection shapes the entire conformational landscape, including uniquely configured conformational substates, the relative distribution of these substates, and the speed at which the protein can interconvert between them. An increased focus on polysterism may shape the way protein structure and function is studied in the coming years.
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Pietsch M, Christian L, Inhester T, Petzold S, Gütschow M. Kinetics of inhibition of acetylcholinesterase in the presence of acetonitrile. FEBS J 2009; 276:2292-307. [PMID: 19292865 DOI: 10.1111/j.1742-4658.2009.06957.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The hydrolysis of acetylthiocholine by acetylcholinesterase from Electrophorus electricus was investigated in the presence of the inhibitors tacrine, gallamine and compound 1. The interaction of the enzyme with the substrate and the inhibitors was characterized by the parameters K(I), alpha', b or beta, K(m) and V(max), which were determined directly and simultaneously from nonlinear Michaelis-Menten plots. Tacrine was shown to act as a mixed-type inhibitor with a strong noncompetitive component (alpha' approximately 1) and to completely block deacylation of the acyl-enzyme. In contrast, acetylcholinesterase inhibition by gallamine followed the 'steric blockade hypothesis', i.e. only substrate association to as well as substrate/product dissociation from the active site were reduced in the presence of the inhibitor. The relative efficiency of the acetylcholinesterase-gallamine complex for the catalysis of substrate conversion was determined to be 1.7-25% of that of the free enzyme. Substrate hydrolysis and the inhibition of acetylcholinesterase were also investigated in the presence of 6% acetonitrile, and a competitive pseudo-inhibition was observed for acetonitrile (K(I) = 0.25 m). The interaction of acetylcholinesterase with acetonitrile and tacrine or gallamine resulted in a seven- to 10-fold increase in the K(I) values, whereas the principal mode of inhibition was not affected by the organic solvent. The determination of the inhibitory parameters of compound 1 in the presence of acetonitrile revealed that the substance acts as a hyperbolic mixed-type inhibitor of acetylcholinesterase. The complex formed by the enzyme and the inhibitor still catalysed product formation with 8.7-9.6% relative efficiency.
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Affiliation(s)
- Markus Pietsch
- Pharmaceutical Chemistry I, Pharmaceutical Institute, University of Bonn, Germany.
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