1
|
Mukhametgalieva A, Mir SA, Shaihutdinova Z, Masson P. Human Plasma Butyrylcholinesterase Hydrolyzes Atropine: Kinetic and Molecular Modeling Studies. Molecules 2024; 29:2140. [PMID: 38731631 PMCID: PMC11085540 DOI: 10.3390/molecules29092140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Revised: 04/29/2024] [Accepted: 05/02/2024] [Indexed: 05/13/2024] Open
Abstract
The participation of butyrylcholinesterase (BChE) in the degradation of atropine has been recurrently addressed for more than 70 years. However, no conclusive answer has been provided for the human enzyme so far. In the present work, a steady-state kinetic analysis performed by spectrophotometry showed that highly purified human plasma BChE tetramer slowly hydrolyzes atropine at pH 7.0 and 25 °C. The affinity of atropine for the enzyme is weak, and the observed kinetic rates versus the atropine concentration was of the first order: the maximum atropine concentration in essays was much less than Km. Thus, the bimolecular rate constant was found to be kcat/Km = 7.7 × 104 M-1 min-1. Rough estimates of catalytic parameters provided slow kcat < 40 min-1 and high Km = 0.3-3.3 mM. Then, using a specific organophosphoryl agent, echothiophate, the time-dependent irreversible inhibition profiles of BChE for hydrolysis of atropine and the standard substrate butyrylthiocholine (BTC) were investigated. This established that both substrates are hydrolyzed at the same site, i.e., S198, as for all substrates of this enzyme. Lastly, molecular docking provided evidence that both atropine isomers bind to the active center of BChE. However, free energy perturbations yielded by the Bennett Acceptance Ratio method suggest that the L-atropine isomer is the most reactive enantiomer. In conclusion, the results provided evidence that plasma BChE slowly hydrolyzes atropine but should have no significant role in its metabolism under current conditions of medical use and even under administration of the highest possible doses of this antimuscarinic drug.
Collapse
Affiliation(s)
- Aliya Mukhametgalieva
- Laboratory of Biochemical Neuropharmacology, Kazan Federal University, Kremlevskaya Str. 18, 420008 Kazan, Russia; (A.M.); (Z.S.)
| | - Showkat Ahmad Mir
- School of Life Sciences, Sambalpur University, Jyotivihar, Burla 768019, India;
| | - Zukhra Shaihutdinova
- Laboratory of Biochemical Neuropharmacology, Kazan Federal University, Kremlevskaya Str. 18, 420008 Kazan, Russia; (A.M.); (Z.S.)
| | - Patrick Masson
- Laboratory of Biochemical Neuropharmacology, Kazan Federal University, Kremlevskaya Str. 18, 420008 Kazan, Russia; (A.M.); (Z.S.)
| |
Collapse
|
2
|
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: 30] [Impact Index Per Article: 10.0] [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.
Collapse
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;
| |
Collapse
|
3
|
Sorin EJ, Alvarado W, Cao S, Radcliffe A, La P, An Y. Ensemble Molecular Dynamics of a Protein-Ligand Complex: Residual Inhibitor Entropy Enhances Drug Potency in Butyrylcholinesterase. ACTA ACUST UNITED AC 2017; 6. [PMID: 28944107 DOI: 10.4172/2167-7662.1000145] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Butyrylcholinesterase is a key enzyme that catalyzes the hydrolysis of the neurotransmitter acetylcholine and shows an increased activity in patients suffering from Alzheimer's disease (AD), making this enzyme a primary target in treating AD. Central to this problem, and to similar scenarios involving biomolecular recognition, is our understanding of the nature of the protein-ligand complex. The butyrylcholinesterase enzyme was studied via all-atom, explicit solvent, ensemble molecular dynamics simulations sans inhibitor and in the presence of three dialkyl phenyl phosphate inhibitors of known potency to a cumulative sampling of over 40 μs. Following the relaxation of these ensembles to conformational equilibria, binding modes for each inhibitor were identified. While classical models, which assume significant reduction in protein and ligand conformational entropies, continue to be favored in contemporary studies, our observations contradict those assumptions: bound ligands occupy many conformational states, thereby stabilizing the complex, while also promoting protein flexibility.
Collapse
Affiliation(s)
- Eric J Sorin
- Department of Chemistry and Biochemistry, California State University Long Beach, California, USA
| | - Walter Alvarado
- Department of Physics and Astronomy, California State University Long Beach, California, USA
| | - Samantha Cao
- Department of Chemistry and Biochemistry, California State University Long Beach, California, USA
| | - Amethyst Radcliffe
- Department of Physics and Astronomy, California State University Long Beach, California, USA
| | - Phuc La
- Department of Chemistry and Biochemistry, California State University Long Beach, California, USA
| | - Yi An
- Department of Chemistry and Biochemistry, California State University Long Beach, California, USA
| |
Collapse
|
4
|
Zhang Y, Huang X, Han K, Zheng F, Zhan CG. Free energy profiles of cocaine esterase-cocaine binding process by molecular dynamics and potential of mean force simulations. Chem Biol Interact 2016; 259:142-147. [PMID: 27163853 DOI: 10.1016/j.cbi.2016.05.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2016] [Revised: 04/29/2016] [Accepted: 05/05/2016] [Indexed: 11/29/2022]
Abstract
The combined molecular dynamics (MD) and potential of mean force (PMF) simulations have been performed to determine the free energy profile of the CocE)-(+)-cocaine binding process in comparison with that of the corresponding CocE-(-)-cocaine binding process. According to the MD simulations, the equilibrium CocE-(+)-cocaine binding mode is similar to the CocE-(-)-cocaine binding mode. However, based on the simulated free energy profiles, a significant free energy barrier (∼5 kcal/mol) exists in the CocE-(+)-cocaine binding process whereas no obvious free energy barrier exists in the CocE-(-)-cocaine binding process, although the free energy barrier of ∼5 kcal/mol is not high enough to really slow down the CocE-(+)-cocaine binding process. In addition, the obtained free energy profiles also demonstrate that (+)-cocaine and (-)-cocaine have very close binding free energies with CocE, with a negligible difference (∼0.2 kcal/mol), which is qualitatively consistent with the nearly same experimental KM values of the CocE enzyme for (+)-cocaine and (-)-cocaine. The consistency between the computational results and available experimental data suggests that the mechanistic insights obtained from this study are reasonable.
Collapse
Affiliation(s)
- Yuxin Zhang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Science, Zhongshan Road 457, Dalian 116023, PR China; Molecular Modeling and Biopharmaceutical Center, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, KY 40536, USA; Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, KY 40536, USA
| | - Xiaoqin Huang
- Molecular Modeling and Biopharmaceutical Center, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, KY 40536, USA
| | - Keli Han
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Science, Zhongshan Road 457, Dalian 116023, PR China
| | - Fang Zheng
- Molecular Modeling and Biopharmaceutical Center, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, KY 40536, USA; Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, KY 40536, USA
| | - Chang-Guo Zhan
- Molecular Modeling and Biopharmaceutical Center, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, KY 40536, USA; Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, KY 40536, USA.
| |
Collapse
|
5
|
Reilly PJ, Rovira C. Computational Studies of Glycoside, Carboxylic Ester, and Thioester Hydrolase Mechanisms: A Review. Ind Eng Chem Res 2015. [DOI: 10.1021/acs.iecr.5b01312] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Peter J. Reilly
- Department
of Chemical and Biological Engineering, Iowa State University, Ames, Iowa 50011-2230, United States
| | - Carme Rovira
- Departament de Química Orgànica
and Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, 08028 Barcelona, Spain
- Institució
Catalana de Recerca i Estudis Avançats (ICREA), 08010 Barcelona, Spain
| |
Collapse
|
6
|
Huang X, Zheng F, Zhan CG. Binding structures and energies of the human neonatal Fc receptor with human Fc and its mutants by molecular modeling and dynamics simulations. MOLECULAR BIOSYSTEMS 2013; 9:3047-58. [PMID: 24057047 DOI: 10.1039/c3mb70231f] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Homology modeling and molecular dynamics simulations have been carried out to model the detailed structures of the human neonatal Fc receptor (FcRn) binding with the wild-type Fc of human immunoglobulin G1 (IgG1) and its various mutants. Based on the modeled human FcRn-Fc binding structures, it has been proposed that the protein-protein binding interface is composed of three subsites. The first subsite is a hydrophobic core where residue I39 of human Fc can be accommodated very well, and the other two subsites are all composed of critical salt bridges between human FcRn and human Fc. All of the modeled structures and the calculated binding energies are qualitatively consistent with the available experimental data, suggesting that the modeled human FcRn-Fc binding structures are reasonable. The modeled human FcRn-Fc binding structure may be valuable for future rational design of novel mutants of human Fc and Fc-fused therapeutic proteins with a potentially higher binding affinity for human FcRn and, thus, a longer in vivo half-life in humans.
Collapse
Affiliation(s)
- Xiaoqin Huang
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, Kentucky 40536, USA.
| | | | | |
Collapse
|
7
|
Hao GF, Tan Y, Yang SG, Wang ZF, Zhan CG, Xi Z, Yang GF. Computational and experimental insights into the mechanism of substrate recognition and feedback inhibition of protoporphyrinogen oxidase. PLoS One 2013; 8:e69198. [PMID: 23935953 PMCID: PMC3720618 DOI: 10.1371/journal.pone.0069198] [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: 03/29/2013] [Accepted: 06/05/2013] [Indexed: 11/20/2022] Open
Abstract
Protoporphyrinogen IX oxidase (PPO; EC 1.3.3.4) is an essential enzyme catalyzing the last common step in the pathway leading to heme and chlorophyll biosynthesis. Great interest in PPO inhibitors arises from both its significance to agriculture and medicine. However, the discovery of PPO inhibitors with ultrahigh potency and selectivity is hampered due to lack of structural and mechanistic understanding about the substrate recognition, which remains a longstanding question central in porphyrin biology. To understand the mechanism, a novel binding model of protogen (protoporphyrinogen IX, the substrate) was developed through extensive computational simulations. Subsequently, amino acid residues that are critical for protogen binding identified by computational simulations were substituted by mutagenesis. Kinetic analyses of these mutants indicated that these residues were critical for protogen binding. In addition, the calculated free energies of protogen binding with these mutants correlated well with the experimental data, indicating the reasonability of the binding model. On the basis of this novel model, the fundamental mechanism of substrate recognition was investigated by performing potential of mean force (PMF) calculations, which provided an atomic level description of conformational changes and pathway intermediates. The free energy profile revealed a feedback inhibition mechanism of proto (protoporphyrin IX, the product), which was also in agreement with experimental evidence. The novel mechanistic insights obtained from this study present a new starting point for future rational design of more efficient PPO inhibitors based on the product-bound PPO structure.
Collapse
Affiliation(s)
- Ge-Fei Hao
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, P. R. China
| | - Ying Tan
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, P. R. China
- State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin, P. R. China
| | - Sheng-Gang Yang
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, P. R. China
| | - Zhi-Fang Wang
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, P. R. China
- State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin, P. R. China
| | - Chang-Guo Zhan
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky, United States of America
| | - Zhen Xi
- State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin, P. R. China
| | - Guang-Fu Yang
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, P. R. China
| |
Collapse
|
8
|
Liu J, Zhan CG. Reaction Pathway and Free Energy Profile for Cocaine Hydrolase-Catalyzed Hydrolysis of (-)-Cocaine. J Chem Theory Comput 2012; 8:1426-1435. [PMID: 23066354 PMCID: PMC3469271 DOI: 10.1021/ct200810d] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Reaction pathway of (-)-cocaine hydrolysis catalyzed by our recently discovered most efficient cocaine hydrolase, which is the A199S/F227A/S287G/A328W/Y332G mutant of human butyrylcholinesterase (BChE), and the corresponding free energy profile have been studied by performing first-principles pseudobond quantum mechanical/molecular mechanical (QM/MM)-free energy (FE) calculations. Based on the QM/MM-FE results, the catalytic hydrolysis process consists of four major reaction steps, including the nucleophilic attack on carbonyl carbon of (-)-cocaine benzoyl ester by hydroxyl group of S198, dissociation of (-)-cocaine benzoyl ester, nucleophilic attack on carbonyl carbon of (-)-cocaine benzoyl ester by water, and finally the dissociation between (-)-cocaine benzoyl group and S198 of the enzyme. The second reaction step is rate-determining. The calculated free energy barrier associated with the transition state for the rate-determining step is ~15.0 kcal/mol, which is in excellent agreement with the experimentally-derived activation free energy of ~14.7 kcal/mol. The mechanistic insights obtained from the present study will be valuable for rational design of more active cocaine hydrolase against (-)-cocaine. In particular, future efforts aiming at further increasing the catalytic activity of the enzyme against (-)-cocaine should focus on stabilization of the transition state for the second reaction step in which the benzoyl ester of (-)-cocaine dissociates.
Collapse
Affiliation(s)
- Junjun Liu
- Tongji School of Pharmacy, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, Hubei 430030, P.R. China
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, KY 40536
| | - Chang-Guo Zhan
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, KY 40536
| |
Collapse
|