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Cossio-Bayugar R, Martinez-Ibañez F, Aguilar-Diaz H, Miranda-Miranda E. Relationship between acaricide resistance and acetylcholinesterase gene polymorphisms in the cattle tick Rhipicephalus microplus. Parasite 2024; 31:3. [PMID: 38315066 PMCID: PMC10840460 DOI: 10.1051/parasite/2024003] [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: 08/24/2023] [Accepted: 01/05/2024] [Indexed: 02/07/2024] Open
Abstract
In this study, we aimed to develop a comprehensive methodology for identifying amino acid polymorphisms in acetylcholinesterase transcript 2 (AChE2) in acaricide-resistant Rhipicephalus microplus ticks. This included assessing AChE2 expression levels through qPCR and conducting 3D modeling to evaluate the interaction between acaricides and AChE2 using docking techniques. The study produced significant results, demonstrating that acaricide-resistant R. microplus ticks exhibit significantly higher levels of AChE expression than susceptible reference ticks. In terms of amino acid sequence, we identified 9 radical amino acid substitutions in AChE2 from acaricide-resistant ticks, when compared to the gene sequence of the susceptible reference strain. To further understand the implications of these substitutions, we utilized 3D acaricide-AChE2 docking modeling to examine the interaction between the acaricide and the AChE2 catalytic site. Our models suggest that these amino acid polymorphisms alter the configuration of the binding pocket, thereby contributing to differences in acaricide interactions and ultimately providing insights into the acaricide-resistance phenomenon in R. microplus.
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Affiliation(s)
- Raquel Cossio-Bayugar
- Centro Nacional de Investigación Disciplinaria en Salud Animal e Inocuidad, Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias INIFAP Boulevard Cuauhnahuac 8534, Jiutepec Morelos CP 625574 México
| | - Francisco Martinez-Ibañez
- Departamento de Ectoparásitos y Dípteros. Servicio Nacional de Sanidad, Inocuidad y Calidad Agroalimentaria SADER Boulevard Cuauhnahuac 8534, Jiutepec Morelos CP 625574 México
| | - Hugo Aguilar-Diaz
- Centro Nacional de Investigación Disciplinaria en Salud Animal e Inocuidad, Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias INIFAP Boulevard Cuauhnahuac 8534, Jiutepec Morelos CP 625574 México
| | - Estefan Miranda-Miranda
- Centro Nacional de Investigación Disciplinaria en Salud Animal e Inocuidad, Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias INIFAP Boulevard Cuauhnahuac 8534, Jiutepec Morelos CP 625574 México
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Chaudhari P, Chau LK, Ngo LT, Chang TC, Chen YL, Huang KT. Competitive Assay for the Ultrasensitive Detection of Organophosphate Pesticides Based on a Fiber-Optic Particle Plasmon Resonance Biosensor and an Acetylcholinesterase Binding Peptide. Anal Chem 2023; 95:14600-14607. [PMID: 37726976 DOI: 10.1021/acs.analchem.3c01960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/21/2023]
Abstract
An acetylcholinesterase (AChE) binding-based biosensor was developed for the ultrasensitive detection of organophosphate (OP) pesticides. The biosensor integrates the technique based on fiber-optic particle plasmon resonance detection and a synthetic AChE binding peptide conjugated with gold nanoparticles on the optical fiber surface via an AChE competitive binding assay. The OP pesticides present in the solution hinder the binding of AChE to the peptide on the biosensor by competing for the binding sites present in AChE. The limit of detection obtained for parathion using this method was observed to be 0.66 ppt (2.3 pM). This method shows a wide linear dynamic range of 6 orders. Furthermore, the use of the AChE binding peptide in the biosensor can better discriminate OPs against carbamates by using only a single biosensor. The practical application of this method was tested using spiked samples, which yielded good recovery and reproducibility. The spiked sample required minimal pretreatment before analysis; hence, this biosensor may also be used in the field.
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Affiliation(s)
- Pallavi Chaudhari
- Department of Chemistry and Biochemistry, National Chung Cheng University, Chiayi 621301, Taiwan
| | - Lai-Kwan Chau
- Department of Chemistry and Biochemistry, National Chung Cheng University, Chiayi 621301, Taiwan
- Center for Nano Bio-Detection, National Chung Cheng University, Chiayi 621301, Taiwan
| | - Loan Thi Ngo
- Department of Chemistry and Biochemistry, National Chung Cheng University, Chiayi 621301, Taiwan
| | - Ting-Chou Chang
- Department of Chemistry and Biochemistry, National Chung Cheng University, Chiayi 621301, Taiwan
| | - Yi-Ling Chen
- Department of Chemistry and Biochemistry, National Chung Cheng University, Chiayi 621301, Taiwan
| | - Kuang-Tse Huang
- Center for Nano Bio-Detection, National Chung Cheng University, Chiayi 621301, Taiwan
- Department of Chemical Engineering, National Chung Cheng University, Chiayi 621301, Taiwan
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3
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Magnetic Molecularly Imprinted Polymer (MMIP) Mediated Bacterial Esterase-Based Assay for Captan Detection in Milk. FOOD ANAL METHOD 2022. [DOI: 10.1007/s12161-021-02221-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Denesyuk A, Dimitriou PS, Johnson MS, Nakayama T, Denessiouk K. The acid-base-nucleophile catalytic triad in ABH-fold enzymes is coordinated by a set of structural elements. PLoS One 2020; 15:e0229376. [PMID: 32084230 PMCID: PMC7034887 DOI: 10.1371/journal.pone.0229376] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 02/05/2020] [Indexed: 01/09/2023] Open
Abstract
The alpha/beta-Hydrolases (ABH) are a structural class of proteins that are found widespread in nature and includes enzymes that can catalyze various reactions in different substrates. The catalytic versatility of the ABH fold enzymes, which has been a valuable property in protein engineering applications, is based on a similar acid-base-nucleophile catalytic mechanism. In our research, we are concerned with the structure that surrounds the key units of the catalytic machinery, and we have previously found conserved structural organizations that coordinate the catalytic acid, the catalytic nucleophile and the residues of the oxyanion hole. Here, we explore the architecture that surrounds the catalytic histidine at the active sites of enzymes from 40 ABH fold families, where we have identified six conserved interactions that coordinate the catalytic histidine next to the catalytic acid and the catalytic nucleophile. Specifically, the catalytic nucleophile is coordinated next to the catalytic histidine by two weak hydrogen bonds, while the catalytic acid is directly involved in the coordination of the catalytic histidine through by two weak hydrogen bonds. The imidazole ring of the catalytic histidine is coordinated by a CH-π contact and a hydrophobic interaction. Moreover, the catalytic triad residues are connected with a residue that is located at the core of the active site of ABH fold, which is suggested to be the fourth member of a “structural catalytic tetrad”. Besides their role in the stability of the catalytic mechanism, the conserved elements of the catalytic site are actively involved in ligand binding and affect other properties of the catalytic activity, such as substrate specificity, enantioselectivity, pH optimum and thermostability of ABH fold enzymes. These properties are regularly targeted in protein engineering applications, and thus, the identified conserved structural elements can serve as potential modification sites in order to develop ABH fold enzymes with altered activities.
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Affiliation(s)
- Alexander Denesyuk
- Structural Bioinformatics Laboratory, Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland
- Institute for Biological Instrumentation of the Russian Academy of Sciences, Federal Research Center “Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences”, Pushchino, Russia
- * E-mail:
| | - Polytimi S. Dimitriou
- Structural Bioinformatics Laboratory, Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland
| | - Mark S. Johnson
- Structural Bioinformatics Laboratory, Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland
| | - Toru Nakayama
- Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, Sendai, Miyagi, Japan
| | - Konstantin Denessiouk
- Structural Bioinformatics Laboratory, Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland
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Liang B, Han L. Displaying of acetylcholinesterase mutants on surface of yeast for ultra-trace fluorescence detection of organophosphate pesticides with gold nanoclusters. Biosens Bioelectron 2019; 148:111825. [PMID: 31677527 DOI: 10.1016/j.bios.2019.111825] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 10/24/2019] [Accepted: 10/25/2019] [Indexed: 01/25/2023]
Abstract
Acetylcholinesterase (AChE) has been widely applied on the enzyme inhibition-based detection of organophosphate pesticides (OPs). To improve the sensitivity of fluorometric OPs assay, great efforts were made to change the fluorometric probes or analytical strategies rather than improve the sensitivity of AChE towards OPs. In this work, AChE wild-type (WT) and mutants (E69Y and E69Y/F330L) from Drosophila were successfully displayed on the surface of yeast through a-agglutinin-mediated microbial surface display system. The location of AChE on yeast surface was confirmed by immunofluorescence analysis. Further, a fluorescence OPs detection method was developed by combining yeast surface-displayed AChE mutants and protein-directed electronegative fluorescent gold nanoclusters (Au NCs). Yeast surface-displayed AChE can catalyze the hydrolysis of acetylthiocholine to produce thiocholine. The electropositive thiocholine can not only bind with AuNCs by Au-S bond but also absorb Au NCs by the electrostatic interaction, leading to the aggregation of AuNCs and corresponding fluorescence quenching. When AChE was incubated with paraoxon, a typical model of OPs, the activity of AChE was inhibited and the thiocholine-induced aggregation of AuNCs was reduced. The fluorescence assay based on Au NCs and yest-AChE-E69Y/F330L exhibited the ultra-sensitivity for ultra-trace OPs and 2-6 orders of magnitude lower detection limit (3.3 × 10-14 M) than those of AChE-WT-based method and other reported methods. In addition, the proposed method showed excellent reliability for the real samples assay. This work would provide an alternative strategy for the improvement of bio-analysis at its source.
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Affiliation(s)
- Bo Liang
- College of Life Sciences, College of Chemistry and Pharmaceutical Sciences, Shandong Province Key Laboratory of Applied Mycology, Qingdao Agricultural University, 700 Changcheng Road, Qingdao, Shandong, 266109, China
| | - Lei Han
- College of Life Sciences, College of Chemistry and Pharmaceutical Sciences, Shandong Province Key Laboratory of Applied Mycology, Qingdao Agricultural University, 700 Changcheng Road, Qingdao, Shandong, 266109, China.
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Patel H, Rawtani D, Agrawal Y. A newly emerging trend of chitosan-based sensing platform for the organophosphate pesticide detection using Acetylcholinesterase- a review. Trends Food Sci Technol 2019. [DOI: 10.1016/j.tifs.2019.01.007] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Nguyen HH, Lee SH, Lee UJ, Fermin CD, Kim M. Immobilized Enzymes in Biosensor Applications. MATERIALS (BASEL, SWITZERLAND) 2019; 12:E121. [PMID: 30609693 PMCID: PMC6337536 DOI: 10.3390/ma12010121] [Citation(s) in RCA: 207] [Impact Index Per Article: 41.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 12/15/2018] [Accepted: 12/24/2018] [Indexed: 11/17/2022]
Abstract
Enzyme-based biosensing devices have been extensively developed over the last few decades, and have proven to be innovative techniques in the qualitative and quantitative analysis of a variety of target substrates over a wide range of applications. Distinct advantages that enzyme-based biosensors provide, such as high sensitivity and specificity, portability, cost-effectiveness, and the possibilities for miniaturization and point-of-care diagnostic testing make them more and more attractive for research focused on clinical analysis, food safety control, or disease monitoring purposes. Therefore, this review article investigates the operating principle of enzymatic biosensors utilizing electrochemical, optical, thermistor, and piezoelectric measurement techniques and their applications in the literature, as well as approaches in improving the use of enzymes for biosensors.
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Affiliation(s)
- Hoang Hiep Nguyen
- BioNanotechnology Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahangno, Yuseong-Gu, Daejeon 34141, Korea.
- Department of Nanobiotechnology, KRIBB School of Biotechnology, Korea University of Science and Technology (UST), 217 Gajeongno, Yuseong-Gu, Daejeon 34113, Korea.
| | - Sun Hyeok Lee
- BioNanotechnology Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahangno, Yuseong-Gu, Daejeon 34141, Korea.
- Department of Nanobiotechnology, KRIBB School of Biotechnology, Korea University of Science and Technology (UST), 217 Gajeongno, Yuseong-Gu, Daejeon 34113, Korea.
| | - Ui Jin Lee
- BioNanotechnology Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahangno, Yuseong-Gu, Daejeon 34141, Korea.
- Department of Biochemistry, College of Natural Sciences, Chungnam National University, 99 Daehangno, Yuseong-Gu, Daejeon 34134, Korea.
| | - Cesar D Fermin
- Department of Biology, College of Arts & Sciences, Tuskegee University, Tuskegee, AL 36830, USA.
| | - Moonil Kim
- BioNanotechnology Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahangno, Yuseong-Gu, Daejeon 34141, Korea.
- Department of Nanobiotechnology, KRIBB School of Biotechnology, Korea University of Science and Technology (UST), 217 Gajeongno, Yuseong-Gu, Daejeon 34113, Korea.
- Department of Biology, College of Arts & Sciences, Tuskegee University, Tuskegee, AL 36830, USA.
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Xu YL, Li FY, Ndikuryayo F, Yang WC, Wang HM. Cholinesterases and Engineered Mutants for the Detection of Organophosphorus Pesticide Residues. SENSORS (BASEL, SWITZERLAND) 2018; 18:E4281. [PMID: 30563111 PMCID: PMC6312092 DOI: 10.3390/s18124281] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 11/27/2018] [Accepted: 12/01/2018] [Indexed: 02/04/2023]
Abstract
Nowadays, pesticide residues constitute an increasing public health concern. Cholinesterases, acetylcholinesterase, and butyrylcholinesterase, are reported to be involved in detoxification processes owing to their capability of scavenging organophosphates and carbamates. Thus, these enzymes are targeted for the discovery of sensors aiming at detecting pesticide residues. In recent years, cholinesterase-based biosensors have attracted more and more attention in the detection of pesticides. Herein, this review describes the recent progress on the engineering of cholinesterases and the development of the corresponding sensors that could be used for the detection of organophosphorus pesticide residues.
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Affiliation(s)
- Yu-Ling Xu
- School of Chemical & Environmental Engineering, Wuhan Polytechnic University, Wuhan 430023, China.
| | - Feng-Ye Li
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, and International Joint Research Center for Intelligent Biosensor Technology and Health, and Chemical Biology Center, College of Chemistry, Central China Normal University, Wuhan 430079, China.
| | - Ferdinand Ndikuryayo
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, and International Joint Research Center for Intelligent Biosensor Technology and Health, and Chemical Biology Center, College of Chemistry, Central China Normal University, Wuhan 430079, China.
| | - Wen-Chao Yang
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, and International Joint Research Center for Intelligent Biosensor Technology and Health, and Chemical Biology Center, College of Chemistry, Central China Normal University, Wuhan 430079, China.
| | - Hong-Mei Wang
- Hubei Key Laboratory of Wudang Local Chinese Medicine Research, School of Pharmacy, Hubei University of Medicine, Shiyan 442000, China.
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10
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Pyrethroid Acaricide Resistance Is Proportional to P-450 Cytochrome Oxidase Expression in the Cattle Tick Rhipicephalus microplus. BIOMED RESEARCH INTERNATIONAL 2018; 2018:8292465. [PMID: 30069481 PMCID: PMC6057400 DOI: 10.1155/2018/8292465] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 05/07/2018] [Accepted: 06/12/2018] [Indexed: 01/16/2023]
Abstract
The goal of the present study was to assess the gene expression of xenobiotic metabolizing enzymes (XMEs) Cytochrome P-450 (CYP) and carboxylesterase (CE) related to detoxification of synthetic pyrethroids, plus acetylcholinesterase (AChE), in field isolates of acaricide-resistant Rhipicephalus microplus. The XMEs expression levels were assessed by mRNA measurement using quantitative reverse transcription PCR. The XME expression levels of field-isolated acaricide-resistant ticks were compared against acaricide-susceptible reference ticks used in this study as a gene expression baseline and represented as relative expression units (REU). Field isolates were subjected to toxicological bioassays and determined resistant to all the Pyr acaricides (Pyr), whereas most of them were found susceptible to organophosphorous acaricides (OP), with the exception of three isolates, which exhibited moderate resistance to Diazinon. Significantly higher levels of CYP were detected in pyrethroid-resistance ticks when compared to Su ticks (P<0.01). A linear regression analysis showed that pyrethroid acaricide resistance levels of R. microplus were proportional to the CYP expression levels (correlation coefficient (R):0.85; P<0.05). Analysis on CE expression levels showed only one isolate resistant to Pyr and OP with a statistically significant increase (P<0.01). AChE expression levels showed statistically significant (P<0.01) subexpression in all tick isolates when compared to the susceptible reference. Our results suggest that pyrethroid acaricide resistance in the cattle tick may be diagnosed by measuring the CYP expression levels using quantitative PCR.
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11
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Pathophysiological mechanisms of poisoning. INDIAN JOURNAL OF MEDICAL SPECIALITIES 2018. [DOI: 10.1016/j.injms.2018.05.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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12
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In silico approaches to evaluate the molecular properties of organophosphate compounds to inhibit acetylcholinesterase activity in housefly. J Biomol Struct Dyn 2018; 37:307-320. [PMID: 29322868 DOI: 10.1080/07391102.2018.1426046] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Organophosphate compounds (OPC) have become the primary choice as insecticides and are widely used across the world. Additionally, OPCs were also commonly used as a chemical warfare agent that triggers a great challenge to public safety. Exposure of OPCs to human causes immediate excitation of cholinergic neurotransmission through transient elevation of synaptic acetylcholine (ACh) levels and accumulations. Likewise, prolonged exposure of OPCs can affect the processes in immune response, carbohydrate metabolism, cardiovascular toxicity, and several others. Studies revealed that the toxicity of OPCs was provoked by inhibition of acetylcholinesterase (AChE). Therefore, combined in silico approaches - pharmacophore-based 3D-QSAR model; docking and Molecular Dynamics (MD) - were used to assess the precise and comprehensive effects of series of known OP-derived compounds together with its -log LD50 values. The selected five-featured pharmacophore model - AAHHR.61 - displayed the highest correlation (R2 = .9166), cross-validated coefficient (Q2 = .8221), F = 63.2, Pearson-R = .9615 with low RMSE = .2621 values obtained using five component PLS factors. Subsequently, the well-validated model was then used as a 3D query to search novel OPCs using a high-throughput virtual screening technique. Simultaneously, the docking studies predicted the binding pose of the most active OPC in the MdAChE binding pocket. Additionally, the stability of docking was verified using MD simulation. The results revealed that OP22 and predicted lead compounds bound tightly to S315 of MdAChE through potential hydrogen bond interaction over time. Overall, this study might provide valuable insight into binding mode of OPCs and hit compounds to inhibit AChE in housefly.
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Tiwari RK, Singh S, Pandey RS. Assessment of the acute toxicity of chlorpyrifos and cypermethrin to Heteropneustes fossilis and their impact on acetylcholinesterase activity. Drug Chem Toxicol 2017; 42:463-470. [DOI: 10.1080/01480545.2017.1410171] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Rishikesh K. Tiwari
- Biochemistry Laboratory, Department of Zoology, University of Allahabad, Allahabad, India
| | - Shikha Singh
- Biochemistry Laboratory, Department of Zoology, University of Allahabad, Allahabad, India
| | - Ravi S. Pandey
- Biochemistry Laboratory, Department of Zoology, University of Allahabad, Allahabad, India
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14
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Singh S, Tiwari RK, Pandey RS. Evaluation of acute toxicity of triazophos and deltamethrin and their inhibitory effect on AChE activity in Channa punctatus. Toxicol Rep 2017; 5:85-89. [PMID: 29379743 PMCID: PMC5773704 DOI: 10.1016/j.toxrep.2017.12.006] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 11/22/2017] [Accepted: 12/08/2017] [Indexed: 02/04/2023] Open
Abstract
Pesticides are applied to control the pests indoor and outdoor; however, their remarkable amount reaches to the aquatic system through various routes like run-off, leaching, spray-drift, effluent from factories. These are reported to have negative metabolic impact on different non-target aquatic organisms like fishes. Thus, present study is aimed to evaluate the acute toxicity of two groups of pesticides, organophosphate and pyrethroid, namely triazophos and deltamethrin, respectively. The test was conducted for 96 h period in a freshwater teleost, Channa punctatus. The LC50 values for triazophos and deltamethrin after 96 h treatment was found to be 0.069 mg/L and 7.33 μg/L. The deltamethrin was found to be about ten times more toxic than triazophos to the fish. In treated fish, alterations in various behavioural patterns were observed with increasing concentrations of both the pesticides as compared to control. Further, tissue specific as well as dose dependent inhibition in the acetylcholinesterase (AChE, EC 3.1.1.7) activity was found in brain, muscle and gills in Channa punctatus exposed to both the insecticides. However, the effect was more pronounced in triazophos treated fishes than the deltamethrin. A futuristic approach on biochemical and molecular studies may throw light on the mechanism of action of these pesticides.
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Affiliation(s)
- Shikha Singh
- Biochemistry Laboratory, Department of Zoology, University of Allahabad, Allahabad- 211002, India
| | - Rishikesh K Tiwari
- Biochemistry Laboratory, Department of Zoology, University of Allahabad, Allahabad- 211002, India
| | - Ravi S Pandey
- Biochemistry Laboratory, Department of Zoology, University of Allahabad, Allahabad- 211002, India
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15
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Biosensor-assisted selection of optimal parameters for designing molecularly imprinted polymers selective to phosmet insecticide. Talanta 2017; 174:414-419. [PMID: 28738601 DOI: 10.1016/j.talanta.2017.06.035] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 06/06/2017] [Accepted: 06/12/2017] [Indexed: 11/22/2022]
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16
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Lutz S, Williams E, Muthu P. Engineering Therapeutic Enzymes. DIRECTED ENZYME EVOLUTION: ADVANCES AND APPLICATIONS 2017:17-67. [DOI: 10.1007/978-3-319-50413-1_2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
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17
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Marques SM, Daniel L, Buryska T, Prokop Z, Brezovsky J, Damborsky J. Enzyme Tunnels and Gates As Relevant Targets in Drug Design. Med Res Rev 2016; 37:1095-1139. [PMID: 27957758 DOI: 10.1002/med.21430] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 10/11/2016] [Accepted: 11/07/2016] [Indexed: 12/28/2022]
Abstract
Many enzymes contain tunnels and gates that are essential to their function. Gates reversibly switch between open and closed conformations and thereby control the traffic of small molecules-substrates, products, ions, and solvent molecules-into and out of the enzyme's structure via molecular tunnels. Many transient tunnels and gates undoubtedly remain to be identified, and their functional roles and utility as potential drug targets have received comparatively little attention. Here, we describe a set of general concepts relating to the structural properties, function, and classification of these interesting structural features. In addition, we highlight the potential of enzyme tunnels and gates as targets for the binding of small molecules. The different types of binding that are possible and the potential pharmacological benefits of such targeting are discussed. Twelve examples of ligands bound to the tunnels and/or gates of clinically relevant enzymes are used to illustrate the different binding modes and to explain some new strategies for drug design. Such strategies could potentially help to overcome some of the problems facing medicinal chemists and lead to the discovery of more effective drugs.
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Affiliation(s)
- Sergio M Marques
- Loschmidt Laboratories, Faculty of Science, Department of Experimental Biology and Research Centre for Toxic Compounds in the Environment, RECETOX, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic
| | - Lukas Daniel
- Loschmidt Laboratories, Faculty of Science, Department of Experimental Biology and Research Centre for Toxic Compounds in the Environment, RECETOX, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic.,International Centre for Clinical Research, St. Anne's University Hospital, Pekarska 53, 656 91, Brno, Czech Republic
| | - Tomas Buryska
- Loschmidt Laboratories, Faculty of Science, Department of Experimental Biology and Research Centre for Toxic Compounds in the Environment, RECETOX, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic.,International Centre for Clinical Research, St. Anne's University Hospital, Pekarska 53, 656 91, Brno, Czech Republic
| | - Zbynek Prokop
- Loschmidt Laboratories, Faculty of Science, Department of Experimental Biology and Research Centre for Toxic Compounds in the Environment, RECETOX, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic.,International Centre for Clinical Research, St. Anne's University Hospital, Pekarska 53, 656 91, Brno, Czech Republic
| | - Jan Brezovsky
- Loschmidt Laboratories, Faculty of Science, Department of Experimental Biology and Research Centre for Toxic Compounds in the Environment, RECETOX, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic.,International Centre for Clinical Research, St. Anne's University Hospital, Pekarska 53, 656 91, Brno, Czech Republic
| | - Jiri Damborsky
- Loschmidt Laboratories, Faculty of Science, Department of Experimental Biology and Research Centre for Toxic Compounds in the Environment, RECETOX, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic.,International Centre for Clinical Research, St. Anne's University Hospital, Pekarska 53, 656 91, Brno, Czech Republic
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El-Moghazy AY, Soliman EA, Ibrahim HZ, Noguer T, Marty JL, Istamboulie G. Ultra-sensitive biosensor based on genetically engineered acetylcholinesterase immobilized in poly (vinyl alcohol)/Fe-Ni alloy nanocomposite for phosmet detection in olive oil. Food Chem 2016; 203:73-78. [PMID: 26948591 DOI: 10.1016/j.foodchem.2016.02.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Revised: 01/13/2016] [Accepted: 02/01/2016] [Indexed: 10/22/2022]
Abstract
An ultra-sensitive screen-printed biosensor was successfully developed for phosmet detection in olive oil, based on a genetically-engineered acetylcholinesterase (AChE) immobilized in a azide-unit water-pendant polyvinyl alcohol (PVA-AWP)/Fe-Ni alloy nanocomposite. Fe-Ni not only allowed amplifying the response current but also lowering the applied potential from 80 mV to 30 mV vs Ag/AgCl. The biosensor showed a very good analytical performance for phosmet detection, with a detection limit of 0.1 nM. This detection limit is lower than the allowable concentrations set by international regulations. In addition to the good reproducibility, operational and storage stability, the developed biosensor was successfully used for the determination of phosmet in olive oil samples without any laborious pre-treatment. The phosmet recovery rate was about 96% after a simple liquid-liquid extraction.
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Affiliation(s)
- A Y El-Moghazy
- BAE: Biocapteurs-Analyss-Environnement, Université de Perpignan Via Domitia, 52 Avenue Paul Alduy, Perpignan Cedex 66860, France; Polymeric Materials Department, Advanced Technology and New Materials Research Institute, City of Scientific Research and Technological Applications (SRTA-City), New Borg El-Arab City, Alexandria, P.O. Box: 21934, Egypt
| | - E A Soliman
- Polymeric Materials Department, Advanced Technology and New Materials Research Institute, City of Scientific Research and Technological Applications (SRTA-City), New Borg El-Arab City, Alexandria, P.O. Box: 21934, Egypt
| | - H Z Ibrahim
- Department of Environmental Studies, Institute of Graduate Studies and Research, Alexandria University, P.O. Box 832, Alexandria, Egypt
| | - T Noguer
- BAE: Biocapteurs-Analyss-Environnement, Université de Perpignan Via Domitia, 52 Avenue Paul Alduy, Perpignan Cedex 66860, France
| | - J-L Marty
- BAE: Biocapteurs-Analyss-Environnement, Université de Perpignan Via Domitia, 52 Avenue Paul Alduy, Perpignan Cedex 66860, France
| | - G Istamboulie
- BAE: Biocapteurs-Analyss-Environnement, Université de Perpignan Via Domitia, 52 Avenue Paul Alduy, Perpignan Cedex 66860, France
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Kaur K, Helgesen KO, Bakke MJ, Horsberg TE. Mechanism behind Resistance against the Organophosphate Azamethiphos in Salmon Lice (Lepeophtheirus salmonis). PLoS One 2015; 10:e0124220. [PMID: 25893248 PMCID: PMC4403986 DOI: 10.1371/journal.pone.0124220] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 03/10/2015] [Indexed: 11/18/2022] Open
Abstract
Acetylcholinesterase (AChE) is the primary target for organophosphates (OP). Several mutations have been reported in AChE to be associated with the reduced sensitivity against OP in various arthropods. However, to the best of our knowledge, no such reports are available for Lepeophtheirus salmonis. Hence, in the present study, we aimed to determine the association of AChE(s) gene(s) with resistance against OP. We screened the AChE genes (L. salmonis ace1a and ace1b) in two salmon lice populations: one sensitive (n=5) and the other resistant (n=5) for azamethiphos, a commonly used OP in salmon farming. The screening led to the identification of a missense mutation Phe362Tyr in L. salmonis ace1a, (corresponding to Phe331 in Torpedo californica AChE) in all the samples of the resistant population. We confirmed the potential role of the mutation, with reduced sensitivity against azamethiphos in L. salmonis, by screening for Phe362Tyr in 2 sensitive and 5 resistant strains. The significantly higher frequency of the mutant allele (362Tyr) in the resistant strains clearly indicated the possible association of Phe362Tyr mutation in L. salmonis ace1a with resistance towards azamethiphos. The 3D modelling, short term survival experiments and enzymatic assays further supported the imperative role of Phe362Tyr in reduced sensitivity of L. salmonis for azamethiphos. Based on all these observations, the present study, for the first time, presents the mechanism of resistance in L. salmonis against azamethiphos. In addition, we developed a rapid diagnostic tool for the high throughput screening of Phe362Tyr mutation using High Resolution Melt analysis.
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Affiliation(s)
- Kiranpreet Kaur
- NMBU School of Veterinary Science, Sea Lice Research Centre, PO Box 8146 Dep., NO-0033 Oslo, Norway
- * E-mail:
| | - Kari Olli Helgesen
- NMBU School of Veterinary Science, Sea Lice Research Centre, PO Box 8146 Dep., NO-0033 Oslo, Norway
| | - Marit Jørgensen Bakke
- NMBU School of Veterinary Science, Sea Lice Research Centre, PO Box 8146 Dep., NO-0033 Oslo, Norway
| | - Tor Einar Horsberg
- NMBU School of Veterinary Science, Sea Lice Research Centre, PO Box 8146 Dep., NO-0033 Oslo, Norway
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Diethyl 2-(phenylcarbamoyl)phenyl phosphorothioates: synthesis, antimycobacterial activity and cholinesterase inhibition. Molecules 2014; 19:7152-68. [PMID: 24886941 PMCID: PMC6271228 DOI: 10.3390/molecules19067152] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 05/26/2014] [Accepted: 05/27/2014] [Indexed: 11/17/2022] Open
Abstract
A new series of 27 diethyl 2-(phenylcarbamoyl)phenyl phosphorothioates (thiophosphates) was synthesized, characterized by NMR, IR and CHN analyses and evaluated against Mycobacterium tuberculosis H37Rv, Mycobacterium avium and two strains of Mycobacterium kansasii. The best activity against M. tuberculosis was found for O-{4-bromo-2-[(3,4-dichlorophenyl)carbamoyl]phenyl} O,O-diethyl phosphorothioate (minimum inhibitory concentration of 4 µM). The highest activity against nontuberculous mycobacteria was exhibited by O-(5-chloro-2-{[4-(trifluoromethyl)phenyl]carbamoyl}-phenyl) O,O-diethyl phosphorothioate with MIC values from 16 µM. Prepared thiophosphates were also evaluated against acetylcholinesterase from electric eel and butyrylcholinesterase from equine serum. Their inhibitory activity was compared to that of the known cholinesterases inhibitors galanthamine and rivastigmine. All tested compounds showed a higher (for AChE inhibition) and comparable (for BChE inhibition) activity to that of rivastigmine, with IC50s within the 8.04 to 20.2 µM range.
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Acetylcholinesterase biosensors for electrochemical detection of organophosphorus compounds: a review. Biochem Res Int 2013; 2013:731501. [PMID: 24383001 PMCID: PMC3872028 DOI: 10.1155/2013/731501] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Accepted: 10/03/2013] [Indexed: 11/17/2022] Open
Abstract
The exponentially growing population, with limited resources, has exerted an intense pressure on the agriculture sector. In order to achieve high productivity the use of pesticide has increased up to many folds. These pesticides contain organophosphorus (OP) toxic compounds which interfere with the proper functioning of enzyme acetylcholinesterase (AChE) and finally affect the central nervous system (CNS). So, there is a need for routine, continuous, on spot detection of OP compounds which are the main limitations associated with conventional analytical methods. AChE based enzymatic biosensors have been reported by researchers as the most promising tool for analysis of pesticide level to control toxicity and for environment conservation. The present review summarises AChE based biosensors by discussing their characteristic features in terms of fabrication, detection limit, linearity range, time of incubation, and storage stability. Use of nanoparticles in recently reported fabrication strategies has improved the efficiency of biosensors to a great extent making them more reliable and robust.
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Surface display of recombinant Drosophila melanogaster acetylcholinesterase for detection of organic phosphorus and carbamate pesticides. PLoS One 2013; 8:e72986. [PMID: 24039837 PMCID: PMC3767663 DOI: 10.1371/journal.pone.0072986] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Accepted: 07/23/2013] [Indexed: 11/18/2022] Open
Abstract
Acetylcholinesterase (AChE) is commonly used for the detection of organophosphate (OP) and carbamate (CB) insecticides. However, the cost of this commercially available enzyme is high, making high-throughput insecticide detection improbable. In this study we constructed a new AChE yeast expression system in Saccharomyces cerevisiae for the expression of a highly reactive recombinant AChE originating from Drosophila melanogaster (DmAChE). Specifically, the coding sequence of DmAChE was fused with the 3′-terminal half of an α-agglutinin anchor region, along with an antigen tag for the detection of the recombinant protein. The target sequence was cloned into the yeast expression vector pYes-DEST52, and the signal peptide sequence was replaced with a glucoamylase secretion region for induced expression. The resultant engineered vector was transformed into S. cerevisiae. DmAChE was expressed and displayed on the cell surface after galactose induction. Our results showed that the recombinant protein displayed activity comparable to the commercial enzyme. We also detected different types of OP and CB insecticides through enzyme inhibition assays, with the expressed DmAChE showing high sensitivity. These results show the construction of a new yeast expression system for DmAChE, which can subsequently be used for detecting OP and CB insecticides with reduced economic costs.
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Čolović MB, Krstić DZ, Lazarević-Pašti TD, Bondžić AM, Vasić VM. Acetylcholinesterase inhibitors: pharmacology and toxicology. Curr Neuropharmacol 2013; 11:315-35. [PMID: 24179466 PMCID: PMC3648782 DOI: 10.2174/1570159x11311030006] [Citation(s) in RCA: 1372] [Impact Index Per Article: 124.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Revised: 01/04/2013] [Accepted: 02/02/2013] [Indexed: 12/12/2022] Open
Abstract
Acetylcholinesterase is involved in the termination of impulse transmission by rapid hydrolysis of the neurotransmitter acetylcholine in numerous cholinergic pathways in the central and peripheral nervous systems. The enzyme inactivation, induced by various inhibitors, leads to acetylcholine accumulation, hyperstimulation of nicotinic and muscarinic receptors, and disrupted neurotransmission. Hence, acetylcholinesterase inhibitors, interacting with the enzyme as their primary target, are applied as relevant drugs and toxins. This review presents an overview of toxicology and pharmacology of reversible and irreversible acetylcholinesterase inactivating compounds. In the case of reversible inhibitors being commonly applied in neurodegenerative disorders treatment, special attention is paid to currently approved drugs (donepezil, rivastigmine and galantamine) in the pharmacotherapy of Alzheimer's disease, and toxic carbamates used as pesticides. Subsequently, mechanism of irreversible acetylcholinesterase inhibition induced by organophosphorus compounds (insecticides and nerve agents), and their specific and nonspecific toxic effects are described, as well as irreversible inhibitors having pharmacological implementation. In addition, the pharmacological treatment of intoxication caused by organophosphates is presented, with emphasis on oxime reactivators of the inhibited enzyme activity administering as causal drugs after the poisoning. Besides, organophosphorus and carbamate insecticides can be detoxified in mammals through enzymatic hydrolysis before they reach targets in the nervous system. Carboxylesterases most effectively decompose carbamates, whereas the most successful route of organophosphates detoxification is their degradation by corresponding phosphotriesterases.
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Affiliation(s)
- Mirjana B Čolović
- Department of Physical Chemistry, Vinča Institute of Nuclear Sciences, University of Belgrade, Belgrade, Serbia
| | - Danijela Z Krstić
- University School of Medicine, Institute of Medical Chemistry, University of Belgrade, Belgrade, Serbia
| | - Tamara D Lazarević-Pašti
- Department of Physical Chemistry, Vinča Institute of Nuclear Sciences, University of Belgrade, Belgrade, Serbia
| | - Aleksandra M Bondžić
- Department of Physical Chemistry, Vinča Institute of Nuclear Sciences, University of Belgrade, Belgrade, Serbia
| | - Vesna M Vasić
- Department of Physical Chemistry, Vinča Institute of Nuclear Sciences, University of Belgrade, Belgrade, Serbia
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Prabhulkar S, Tian H, Wang X, Zhu JJ, Li CZ. Engineered proteins: redox properties and their applications. Antioxid Redox Signal 2012; 17:1796-822. [PMID: 22435347 PMCID: PMC3474195 DOI: 10.1089/ars.2011.4001] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2011] [Revised: 03/20/2012] [Accepted: 03/21/2012] [Indexed: 10/28/2022]
Abstract
Oxidoreductases and metalloproteins, representing more than one third of all known proteins, serve as significant catalysts for numerous biological processes that involve electron transfers such as photosynthesis, respiration, metabolism, and molecular signaling. The functional properties of the oxidoreductases/metalloproteins are determined by the nature of their redox centers. Protein engineering is a powerful approach that is used to incorporate biological and abiological redox cofactors as well as novel enzymes and redox proteins with predictable structures and desirable functions for important biological and chemical applications. The methods of protein engineering, mainly rational design, directed evolution, protein surface modifications, and domain shuffling, have allowed the creation and study of a number of redox proteins. This review presents a selection of engineered redox proteins achieved through these methods, resulting in a manipulation in redox potentials, an increase in electron-transfer efficiency, and an expansion of native proteins by de novo design. Such engineered/modified redox proteins with desired properties have led to a broad spectrum of practical applications, ranging from biosensors, biofuel cells, to pharmaceuticals and hybrid catalysis. Glucose biosensors are one of the most successful products in enzyme electrochemistry, with reconstituted glucose oxidase achieving effective electrical communication with the sensor electrode; direct electron-transfer-type biofuel cells are developed to avoid thermodynamic loss and mediator leakage; and fusion proteins of P450s and redox partners make the biocatalytic generation of drug metabolites possible. In summary, this review includes the properties and applications of the engineered redox proteins as well as their significance and great potential in the exploration of bioelectrochemical sensing devices.
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Affiliation(s)
- Shradha Prabhulkar
- Nanobioengineering/Bioelectronics Laboratory, Department of Biomedical Engineering, Florida International University, Miami, Florida
| | - Hui Tian
- Department of Chemistry and Biochemistry, Florida International University, Miami, Florida
| | - Xiaotang Wang
- Department of Chemistry and Biochemistry, Florida International University, Miami, Florida
| | - Jun-Jie Zhu
- Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, China
| | - Chen-Zhong Li
- Nanobioengineering/Bioelectronics Laboratory, Department of Biomedical Engineering, Florida International University, Miami, Florida
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25
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Enantioselective inhibition of immobilized acetylcholinesterase in biosensor determination of pesticides. OPEN CHEM 2012. [DOI: 10.2478/s11532-012-0101-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractChiral effects for the inhibition of acetylcholinesterase by organophosphorus pesticides were investigated for insecticide malathion and malaoxon, which is a metabolic product of malathion in living organisms. Studies were carried out using a bienzymatic biosensor with immobilized acetylcholinesterase, choline oxidase, and with Prussian Blue used as a mediator. In both cases the R enantiomers accelerate acetylocholinesterase inhibition. The chiral effect in inhibition was much more pronounced in fast flow measurements than in batch measurements.
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Ben Oujji N, Bakas I, Istamboulié G, Ait-Ichou I, Ait-Addi E, Rouillon R, Noguer T. Acetylcholinesterase immobilized on magnetic beads for pesticides detection: application to olive oil analysis. SENSORS 2012; 12:7893-904. [PMID: 22969377 PMCID: PMC3436006 DOI: 10.3390/s120607893] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Revised: 05/24/2012] [Accepted: 06/04/2012] [Indexed: 11/22/2022]
Abstract
This work presents the development of bioassays and biosensors for the detection of insecticides widely used in the treatment of olive trees. The systems are based on the covalent immobilisation of acetylcholinesterase on magnetic microbeads using either colorimetry or amperometry as detection technique. The magnetic beads were immobilised on screen-printed electrodes or microtitration plates and tested using standard solutions and real samples. The developed devices showed good analytical performances with limits of detection much lower than the maximum residue limit tolerated by international regulations, as well as a good reproducibility and stability.
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Affiliation(s)
- Najwa Ben Oujji
- IMAGES Laboratory, University of Perpignan, IMAGES EA4218, Building S 52 Av Paul Alduy, 66860 Perpignan Cedex, France; E-Mails: (N.B.O.); (I.B.); (G.I.); (R.R.)
- AQUAMAR Laboratory, Photocatalysis and Environment Team, Department of Chemistry, Faculty of Science, University Ibn Zohr, BP 8106 Cité Dakhla, Agadir, Morocco; E-Mails: (I.A.-I.); (E.A.-A.)
| | - Idriss Bakas
- IMAGES Laboratory, University of Perpignan, IMAGES EA4218, Building S 52 Av Paul Alduy, 66860 Perpignan Cedex, France; E-Mails: (N.B.O.); (I.B.); (G.I.); (R.R.)
- AQUAMAR Laboratory, Photocatalysis and Environment Team, Department of Chemistry, Faculty of Science, University Ibn Zohr, BP 8106 Cité Dakhla, Agadir, Morocco; E-Mails: (I.A.-I.); (E.A.-A.)
| | - Georges Istamboulié
- IMAGES Laboratory, University of Perpignan, IMAGES EA4218, Building S 52 Av Paul Alduy, 66860 Perpignan Cedex, France; E-Mails: (N.B.O.); (I.B.); (G.I.); (R.R.)
| | - Ihya Ait-Ichou
- AQUAMAR Laboratory, Photocatalysis and Environment Team, Department of Chemistry, Faculty of Science, University Ibn Zohr, BP 8106 Cité Dakhla, Agadir, Morocco; E-Mails: (I.A.-I.); (E.A.-A.)
| | - Elhabib Ait-Addi
- AQUAMAR Laboratory, Photocatalysis and Environment Team, Department of Chemistry, Faculty of Science, University Ibn Zohr, BP 8106 Cité Dakhla, Agadir, Morocco; E-Mails: (I.A.-I.); (E.A.-A.)
| | - Régis Rouillon
- IMAGES Laboratory, University of Perpignan, IMAGES EA4218, Building S 52 Av Paul Alduy, 66860 Perpignan Cedex, France; E-Mails: (N.B.O.); (I.B.); (G.I.); (R.R.)
| | - Thierry Noguer
- IMAGES Laboratory, University of Perpignan, IMAGES EA4218, Building S 52 Av Paul Alduy, 66860 Perpignan Cedex, France; E-Mails: (N.B.O.); (I.B.); (G.I.); (R.R.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +33-4-68-66-22-55; Fax: +33-4-68-66-22-23
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Qujeq D, Roushan T, Norouzy A, Habibi-Rezaei M, Mehdinejad-Shani M. Effects of dichlorvos and carbaryl on the activity of free and immobilized acetylcholinesterase. Toxicol Ind Health 2011; 28:291-5. [DOI: 10.1177/0748233711410907] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Acetylcholinesterase (AChE) is responsible for the rapid hydrolytic degradation of the neurotransmitter acetylcholine into inactive products choline and acetic acid. The purpose of this study was to examine the effect of carbaryl and dichlorvos on the activity of AChE. In this experimental study, 60 samples of free and immobilized form of AChE were prepared. Determination of AChE activity followed the Ellman’s method with modifications. Briefly, 200 µl of the enzyme solution was combined with 400 µl of 25 mM phosphate-buffered saline, 200 µl of DTNB [5,5′-dithio-bis(2-nitrobenzoic acid)], and 200 µl of 300 μM acetylthiocholine iodide. Triplicate (1000 µl) samples were transferred to clean 1.5-ml centrifuge tubes, mixed, and held on ice until analysed and the change in absorbance was measured. For inhibition studies, substrate solutions were pre-incubated with dichlorvos and/or carbaryl. Dichlorvos and carbaryl were used at the concentrations of 100 and 500 μM. The activity was evaluated at 412 nm using Ceceil, CE 1020 spectrophotometer. Phosphate buffer (pH 7.35) was used for blanks. AChE activity was quantified as mM/ml/min. AChE activity of free form is more affected by Dichlorvos (0.09 ± 0.03 mM/ml/min) than immobilized form (0.19 ± 0.02 mM/ml/min). AChE activity of free form is more affected by carbaryl (0.11 ± 0.01 mM/ml/min) than immobilized form (0.1 ± 0.04 mM/ml/min). Comparison of mean AChE activity showed that the activity of the enzyme in presence of dichlorvos and carbaryl was significantly lower compared to controls. To calculate the significance of the difference, the t-test for paired values was applied. The results of our study indicate that dichlorvos and carbaryl cause decrease in AChE activity for both free and immobilization form of enzyme. It is therefore concluded that measuring AChE activity is a way to evaluate poisoning with carbaryl and dichlorvos.
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Affiliation(s)
- D Qujeq
- Cellular and Molecular Biology Research Center (CMBRC), Babol University of Medical Sciences, Babol, Iran
- Faculty of Medical Sciences, Department of Biochemistry and Biophysics, Babol University of Medical Sciences, Babol, Iran
| | - T Roushan
- Faculty of Medical Sciences, Department of Biochemistry and Biophysics, Babol University of Medical Sciences, Babol, Iran
| | - A Norouzy
- Faculty of Medical Sciences, Department of Biochemistry and Biophysics, Babol University of Medical Sciences, Babol, Iran
| | - M Habibi-Rezaei
- School of Biology, College of Science, University of Tehran, Iran
| | - M Mehdinejad-Shani
- Faculty of Medical Sciences, Department of Biochemistry and Biophysics, Babol University of Medical Sciences, Babol, Iran
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Del Carlo M, Compagnone D. Recent strategies for the biological sensing of pesticides: from the design to the application in real samples. ACTA ACUST UNITED AC 2010. [DOI: 10.1007/s12566-010-0012-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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31
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Selective spectrophotometric detection of insecticides using cholinesterases, phosphotriesterase and chemometric analysis. Enzyme Microb Technol 2010. [DOI: 10.1016/j.enzmictec.2009.09.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Caruana DJ, Howorka S. Biosensors and biofuel cells with engineered proteins. MOLECULAR BIOSYSTEMS 2010; 6:1548-56. [DOI: 10.1039/c004951d] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Hansmann T, Sanson B, Stojan J, Weik M, Marty JL, Fournier D. Kinetic insight into the mechanism of cholinesterasterase inhibition by aflatoxin B1 to develop biosensors. Biosens Bioelectron 2009; 24:2119-24. [DOI: 10.1016/j.bios.2008.11.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2008] [Revised: 10/13/2008] [Accepted: 11/05/2008] [Indexed: 10/21/2022]
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34
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A review of the use of genetically engineered enzymes in electrochemical biosensors. Semin Cell Dev Biol 2009; 20:3-9. [DOI: 10.1016/j.semcdb.2009.01.009] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2008] [Accepted: 01/23/2009] [Indexed: 11/21/2022]
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Krstić DZ, Colović M, Kralj MB, Franko M, Krinulović K, Trebse P, Vasić V. Inhibition of AChE by malathion and some structurally similar compounds. J Enzyme Inhib Med Chem 2008; 23:562-73. [PMID: 18608787 DOI: 10.1080/14756360701632031] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
Inhibition of bovine erythrocyte acetylcholinesterase (free and immobilized on controlled pore glass) by separate and simultaneous exposure to malathion and malathion transformation products which are generally formed during storage or through natural or photochemical degradation was investigated. Increasing concentrations of malathion, its oxidation product malaoxon, and its isomerisation product isomalathion inhibited free and immobilized AChE in a concentration-dependent manner. KI, the dissociation constant for the initial reversible enzyme inhibitor-complex, and k3, the first order rate constant for the conversion of the reversible complex into the irreversibly inhibited enzyme, were determined from the progressive development of inhibition produced by reaction of native AChE with malathion, malaoxon and isomalathion. KI values of 1.3 x 10(-4) M(-1), 5.6 x 10(-6) M(-1) and 7.2 x 10(-6)M(-1) were obtained for malathion, malaoxon and isomalathion, respectively. The IC50 values for free/immobilized AChE, (3.7 +/- 0.2) x 10(-4) M/(1.6 +/-0.1) x 10(-4), (2.4 +/- 0.3) x 10(-6)/(3.4 +/- 0.1) x 10(-6)M and (3.2 +/- 0.3) x 10(-6) M/(2.7 +/- 0.2) x 10(-6) M, were obtained from the inhibition curves induced by malathion, malaoxon and isomalathion, respectively. However, the products formed due to photoinduced degradation, phosphorodithioic O,O,S-trimethyl ester and O,O-dimethyl thiophosphate, did not noticeably affect enzymatic activity, while diethyl maleate inhibited AChE activity at concentrations > 10mM. Inhibition of acetylcholinesterase increased with the time of exposure to malathion and its inhibiting by-products within the interval from 0 to 5 minutes. Through simultaneous exposure of the enzyme to malaoxon and isomalathion, an additive effect was achieved for lower concentrations of the inhibitors (in the presence of malaoxon/isomalathion at concentrations 2 x 10(-7) M/2 x 10(-7) M, 2 x 10(-7) M/3 x 10(-7)M and 2 x 10(-7) M/4.5 x 109-7) M), while an antagonistic effect was obtained for all higher concentrations of inhibitors. The presence of a non-inhibitory degradation product (phosphorodithioic O,O,S-trimethyl ester) did not affect the inhibition efficiencies of the malathion by-products, malaoxon and isomalathion.
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Affiliation(s)
- Danijela Z Krstić
- Institute of Chemistry, School of Medicine, University of Belgrade, Belgrade, Serbia
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Pohanka M, Kuca K, Jun D. Sensor System Based on Acetylcholinesterase in Homogenous Phase for Analysis of Paraoxon. ANAL LETT 2008. [DOI: 10.1080/00032710802240842] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Stojan J, Ladurantie C, Siadat OR, Paquereau L, Fournier D. Evidence for subdomain flexibility in Drosophila melanogaster acetylcholinesterase. Biochemistry 2008; 47:5599-607. [PMID: 18439026 DOI: 10.1021/bi7025479] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The catalytic domain of the acetylcholinesterases is composed of a single polypeptide chain, the folding of which determines two subdomains. We have linked these two subdomains by mutating two residues, I327 and D375, to cysteines, to form a disulfide bridge. As a consequence, the hydrodynamic radius of the protein was reduced, suggesting that there is some flexibility in the subdomain connection. In addition to the smaller size, the mutated protein is more stable than the wild-type protein. Therefore, the flexibility between the two domains is a weak point in terms of protein stability. As expected from the location of the disulfide bond at the rim of the active site, the kinetic studies show that it affects interactions with peripheral ligands and the entrance of some of the bulkier substrates, like o-nitrophenyl acetate. In addition, the mutations affect the catalytic step for o-nitrophenyl acetate and phosphorylation by organophosphates, suggesting that this movement between the two subdomains is connected with the cooperativity between the peripheral and catalytic sites.
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Affiliation(s)
- Jure Stojan
- Institute of Biochemistry, Faculty of Medicine, University of Ljubljana, Vrazov trg 2, 1000 Ljubljana, Slovenia.
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Ishii A, Takeda S, Hattori S, Sueoka K, Mukasa K. Ultrasensitive detection of organophosphate insecticides by carbon nanotube field-effect transistor. Colloids Surf A Physicochem Eng Asp 2008. [DOI: 10.1016/j.colsurfa.2007.05.071] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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39
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Hart JP, Crew A, Crouch E, Honeychurch KC, Pemberton RM. Some Recent Designs and Developments of Screen‐Printed Carbon Electrochemical Sensors/Biosensors for Biomedical, Environmental, and Industrial Analyses. ANAL LETT 2007. [DOI: 10.1081/al-120030682] [Citation(s) in RCA: 182] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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40
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Cutinase inhibition by means of insecticidal organophosphates and carbamates Part 2: screening of representative insecticides on cutinase activity. Eur Food Res Technol 2007. [DOI: 10.1007/s00217-007-0642-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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41
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Schulze H, Muench SB, Villatte F, Schmid RD, Bachmann TT. Insecticide detection through protein engineering of Nippostrongylus brasiliensis acetylcholinesterase B. Anal Chem 2007; 77:5823-30. [PMID: 16159111 DOI: 10.1021/ac050383p] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The sensitivity of acetylcholinesterase (AChE) biosensors for insecticide detection could be increased substantially by engineering AChE B of Nippostrongylus brasiliensis. The introduction of 10 single and 4 double mutations into the AChE peptide chain led to an increase in sensitivity to 10 of the 11 insecticides tested. The combination of three mutants with the wild-type enzyme in a multienzyme biosensor array enabled the detection of 11 out of the 14 most important organophosphates and carbamates at concentrations below 10 microg/kg, the maximum residue limit of infant food. The detection limit for pirimiphos methyl could be reduced from 10 microg/L to a value as low as 1 ng/L (3.5 x 10(-)(12) mol/L). The newly created biosensors exhibited an extraordinary high storage stability. There was no loss of sensitivity of N. brasiliensis AChE B, immobilized on screen-printed, disposable electrodes, even after 17-month storage at room temperature.
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Affiliation(s)
- Holger Schulze
- Institute of Technical Biochemistry, University of Stuttgart, Allmandring 31, D-70569 Stuttgart, Germany
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42
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Chapter 15 Ultra-sensitive determination of pesticides via cholinesterase-based sensors for environmental analysis. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/s0166-526x(06)49015-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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43
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Hart JP, Crew A, Crouch E, Honeychurch KC, Pemberton RM. Chapter 23 Screen-printed electrochemical (bio)sensors in biomedical, environmental and industrial applications. ELECTROCHEMICAL SENSOR ANALYSIS 2007. [DOI: 10.1016/s0166-526x(06)49023-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Xu S, Wu A, Chen H, Xie Y, Xu Y, Zhang L, Li J, Zhang D. Production of a novel recombinant Drosophila melanogaster acetylcholinesterase for detection of organophosphate and carbamate insecticide residues. ACTA ACUST UNITED AC 2006; 24:253-61. [PMID: 17222583 DOI: 10.1016/j.bioeng.2006.12.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2006] [Revised: 12/12/2006] [Accepted: 12/18/2006] [Indexed: 11/30/2022]
Abstract
A novel recombinant Drosophila melanogaster acetylcholinesterase (R-DmAChE) produced in Pichia pastoris was first reported in this study. We cloned the DmAChE cDNA by reverse transcription PCR with removal of the signal for glycosylphosphatidylinositol (GPI) anchor attachment and the endogenous signal peptide coding sequence, and inserted it into P. pastoris vector pPIC9K under control of the alcohol oxidase gene AOX1 promoter (5'AOX1). The expression cassette of AChE cDNA was then introduced into methylotrophic yeast GS115 and several recombinant strains expressing R-DmAChE were obtained. The secreted R-DmAChE showed high stability in neutral phosphate buffer at 4 degrees C, and its kinetic parameters were identical to those of the native DmAChE. The bimolecular rate constants of R-DmAChE to dichlorvos, aldicarb and carbaryl were ranging from three to six times higher than of native DmAChE. Within six insecticides, the R-DmAChE was more sensitive than EeAChE, NbAChE and HuAChE. For 10 widely used insecticides, the IC50 values to the R-DmAChE were much lower than those to AChEs commonly used in China. With the R-DmAChE-based assay, samples spiked with three concentrations of pesticides caused enzymatic activity inhibition with R.S.D. of 0-13.7%. These results suggest that the R-DmAChE can be useful for detection of organophosphate and carbamate insecticide residues.
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Affiliation(s)
- Songci Xu
- Shanghai Jiao Tong University, Shanghai Institutes for Biological Sciences, Pennsylvania State University Joint Center for Life Sciences, Key Laboratory of Microbial Metabolism, Ministry of Education, Shanghai, PR China
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45
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Walz I, Schwack W. Cutinase inhibition by means of insecticidal organophosphates and carbamates. Eur Food Res Technol 2006. [DOI: 10.1007/s00217-006-0435-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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46
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Detection of dichlorvos residue by flow injection calorimetric biosensor based on immobilized chicken liver esterase. J FOOD ENG 2006. [DOI: 10.1016/j.jfoodeng.2005.02.009] [Citation(s) in RCA: 34] [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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47
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Siadat OR, Lougarre A, Lamouroux L, Ladurantie C, Fournier D. The effect of engineered disulfide bonds on the stability of Drosophila melanogaster acetylcholinesterase. BMC BIOCHEMISTRY 2006; 7:12. [PMID: 16686937 PMCID: PMC1481510 DOI: 10.1186/1471-2091-7-12] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2005] [Accepted: 04/16/2006] [Indexed: 11/10/2022]
Abstract
Background Acetylcholinesterase is irreversibly inhibited by organophosphate and carbamate insecticides allowing its use in biosensors for detection of these insecticides. Drosophila acetylcholinesterase is the most sensitive enzyme known and has been improved by in vitro mutagenesis. However, its stability has to be improved for extensive utilization. Results To create a disulfide bond that could increase the stability of the Drosophila melanogaster acetylcholinesterase, we selected seven positions taking into account first the distance between Cβ of two residues, in which newly introduced cysteines will form the new disulfide bond and second the conservation of the residues in the cholinesterase family. Most disulfide bonds tested did not increase and even decreased the stability of the protein. However, one engineered disulfide bridge, I327C/D375C showed significant stability increase toward denaturation by temperature (170 fold at 50°C), urea, organic solvent and provided resistance to protease degradation. The new disulfide bridge links the N-terminal domain (first 356 aa) to the C-terminal domain. The quantities produced by this mutant were the same as in wild-type flies. Conclusion Addition of a disulfide bridge may either stabilize or unstabilize proteins. One bond out of the 7 tested provided significant stabilisation.
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Affiliation(s)
- Omid Ranaei Siadat
- IPBS-CNRS 205 route de Narbonne, Toulouse, France
- New Ideas Research Group (NIRG), #11, Proshat Alley, Motahhari Street, Tehran, Iran
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Bucur B, Fournier D, Danet A, Marty JL. Biosensors based on highly sensitive acetylcholinesterases for enhanced carbamate insecticides detection. Anal Chim Acta 2006. [DOI: 10.1016/j.aca.2005.12.060] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Ma X, Tan J, Wei D, Zhu P, Sun M. High-level secretion and purification of recombinant acetylcholinesterase from human cerebral tissue in P. pastoris and identification by chromogenic reaction. Appl Microbiol Biotechnol 2006; 72:316-22. [PMID: 16397771 DOI: 10.1007/s00253-005-0260-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2004] [Revised: 11/08/2005] [Accepted: 11/13/2005] [Indexed: 10/25/2022]
Abstract
The gene encoding human cerebral tissue acetylcholinesterase (AChE) was cloned from an 18-week fetal cerebral tissue and expressed in Pichia pastoris. Twenty-two positive transformants were obtained by Mut(+)/Mut(s) phenotypes screening in MD/MM medium and polymerase chain reaction amplification, and four recombinant P. pastoris strains that could secrete active AChE at high level were identified by simple and specific development reaction with indoxyl acetate as the chromogenic substrate. In shake-flask culture induced with methanol, the recombinant human AChE (rhAChE) content was about 76% of the total secreted proteins, and rhAChE activity in supernatant was 40 U/ml. The enzyme was purified through anion-exchange and affinity chromatography. Purity of the rhAChE was up to 96% after the simple purification procedure. The enzymatic activity reached 200 U/mg.
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Affiliation(s)
- Xingyuan Ma
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, China.
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50
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Fournier D. Mutations of acetylcholinesterase which confer insecticide resistance in insect populations. Chem Biol Interact 2005; 157-158:257-61. [PMID: 16274684 DOI: 10.1016/j.cbi.2005.10.040] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Resistance-modified acetylcholinesterases have been described in many insect species and sequencing of their genes has allowed several point mutations to be described. Most mutations line the active site gorge. Each mutation provides a specific resistance pattern: it confers resistance to one insecticide but may increase sensitivity to another. Most mutations alter hydrolysis of the substrate by decreasing the rate of enzyme deacetylation and by diminishing the stability of the enzyme. Mutations are often found in combination in the same protein. This has several consequences: it increases the level of resistance, it enlarges the spectrum of resistance and it may restore the catalytic efficiency of the enzyme. Natural populations are heterogeneous, composed of a mixture of different alleles.
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Affiliation(s)
- D Fournier
- IPBS, Biotechnologie des Proteines, 205 route de Narbonne, 31077 Toulouse, France.
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