1
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Mulashkina TI, Kulakova AM, Khrenova MG. Molecular Basis of the Substrate Specificity of Phosphotriesterase from Pseudomonas diminuta: A Combined QM/MM MD and Electron Density Study. J Chem Inf Model 2024. [PMID: 39255503 DOI: 10.1021/acs.jcim.4c00425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/12/2024]
Abstract
The occurrence of organophosphorus compounds, pesticides, and flame-retardants in wastes is an emerging ecological problem. Bacterial phosphotriesterases are capable of hydrolyzing some of them. We utilize modern molecular modeling tools to study the hydrolysis mechanism of organophosphorus compounds with good and poor leaving groups by phosphotriesterase from Pseudomonas diminuta (Pd-PTE). We compute Gibbs energy profiles for enzymes with different cations in the active site: native Zn2+cations and Co2+cations, which increase the steady-state rate constant. Hydrolysis occurs in two elementary steps via an associative mechanism and formation of the pentacoordinated intermediate. The first step, a nucleophilic attack, occurs with a low energy barrier independently of the substrate. The second step has a low energy barrier and considerable stabilization of products for substrates with good leaving groups. For substrates with poor leaving groups, the reaction products are destabilized relative to the ES complex that suppresses the reaction. The reaction proceeds with low energy barriers for substrates with good leaving groups with both Zn2+and Co2+cations in the active site; thus, the product release is likely to be a limiting step. Electron density and geometry analysis of the QM/MM MD trajectories of the intermediate states with all considered compounds allow us to discriminate substrates by their ability to be hydrolyzed by the Pd-PTE. For hydrolyzable substrates, the cleaving bond between a phosphorus atom and a leaving group is elongated, and electron density depletion is observed on the Laplacian of electron density maps.
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Affiliation(s)
- Tatiana I Mulashkina
- Department of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Moscow 119334, Russia
| | - Anna M Kulakova
- Department of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Moscow 119334, Russia
| | - Maria G Khrenova
- Department of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Moscow 119334, Russia
- Bach Institute of Biochemistry, Federal Research Centre of Biotechnology, Russian Academy of Sciences, Moscow 119071, Russia
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2
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Pashirova T, Salah-Tazdaït R, Tazdaït D, Masson P. Applications of Microbial Organophosphate-Degrading Enzymes to Detoxification of Organophosphorous Compounds for Medical Countermeasures against Poisoning and Environmental Remediation. Int J Mol Sci 2024; 25:7822. [PMID: 39063063 PMCID: PMC11277490 DOI: 10.3390/ijms25147822] [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: 06/17/2024] [Revised: 07/13/2024] [Accepted: 07/15/2024] [Indexed: 07/28/2024] Open
Abstract
Mining of organophosphorous (OPs)-degrading bacterial enzymes in collections of known bacterial strains and in natural biotopes are important research fields that lead to the isolation of novel OP-degrading enzymes. Then, implementation of strategies and methods of protein engineering and nanobiotechnology allow large-scale production of enzymes, displaying improved catalytic properties for medical uses and protection of the environment. For medical applications, the enzyme formulations must be stable in the bloodstream and upon storage and not susceptible to induce iatrogenic effects. This, in particular, includes the nanoencapsulation of bioscavengers of bacterial origin. In the application field of bioremediation, these enzymes play a crucial role in environmental cleanup by initiating the degradation of OPs, such as pesticides, in contaminated environments. In microbial cell configuration, these enzymes can break down chemical bonds of OPs and usually convert them into less toxic metabolites through a biotransformation process or contribute to their complete mineralization. In their purified state, they exhibit higher pollutant degradation efficiencies and the ability to operate under different environmental conditions. Thus, this review provides a clear overview of the current knowledge about applications of OP-reacting enzymes. It presents research works focusing on the use of these enzymes in various bioremediation strategies to mitigate environmental pollution and in medicine as alternative therapeutic means against OP poisoning.
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Affiliation(s)
- Tatiana Pashirova
- Institute of Fundamental Medicine and Biology, Kazan Federal University, 18 Kremlyovskaya St., 420008 Kazan, Russia;
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center of RAS, Arbuzov Str. 8, 420088 Kazan, Russia
| | - Rym Salah-Tazdaït
- Bioengineering and Process Engineering Laboratory (BIOGEP), National Polytechnic School, 10 Rue des Frères Oudek, El Harrach, Algiers 16200, Algeria; (R.S.-T.); (D.T.)
| | - Djaber Tazdaït
- Bioengineering and Process Engineering Laboratory (BIOGEP), National Polytechnic School, 10 Rue des Frères Oudek, El Harrach, Algiers 16200, Algeria; (R.S.-T.); (D.T.)
- Department of Nature and Life Sciences, University of Algiers, Benyoucef Benkhedda, 2 Rue Didouche Mourad, Algiers 16000, Algeria
| | - Patrick Masson
- Institute of Fundamental Medicine and Biology, Kazan Federal University, 18 Kremlyovskaya St., 420008 Kazan, Russia;
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3
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Fu Y, Yu J, Fan F, Wang B, Cao Z. Elucidating the Enzymatic Mechanism of Dihydrocoumarin Degradation: Insight into the Functional Evolution of Methyl-Parathion Hydrolase from QM/MM and MM MD Simulations. J Phys Chem B 2024; 128:5567-5575. [PMID: 38814729 DOI: 10.1021/acs.jpcb.4c00970] [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: 06/01/2024]
Abstract
Methyl-parathion hydrolase (MPH), which evolved from dihydrocoumarin hydrolase, offers one of the most efficient enzymes for the hydrolysis of methyl-parathion. Interestingly, the substrate preference of MPH shifts from the methyl-parathion to the lactone dihydrocoumarin (DHC) after its mutation of five specific residues (R72L, L273F, L258H, T271I, and S193Δ, m5-MPH). Here, extensive QM/MM calculations and MM MD simulations have been used to delve into the structure-function relationship of MPH enzymes and plausible mechanisms for the chemical and nonchemical steps, including the transportation and binding of the substrate DHC to the active site, the hydrolysis reaction, and the product release. The results reveal that the five mutations remodel the active pocket and reposition DHC within the active site, leading to stronger enzyme-substrate interactions. The MM/GBSA-estimated binding free energies are about -20.7 kcal/mol for m5-MPH and -17.1 kcal/mol for wild-type MPH. Furthermore, this conformational adjustment of the protein may facilitate the chemical step of DHC hydrolysis and the product release, although there is a certain influence on the substrate transport. The hydrolytic reaction begins with the nucleophilic attack of the bridging OH- with the energy barriers of 22.0 and 18.0 kcal/mol for the wild-type and m5-MPH enzymes, respectively, which is rate-determining for the entire process. Unraveling these mechanistic intricacies may help in the understanding of the natural evolution of enzymes for diverse substrates and establish the enzyme structure-function relationship.
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Affiliation(s)
- Yuzhuang Fu
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Jun Yu
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Fangfang Fan
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
- School of Biological and Chemical Engineering, Zhejiang University of Science and Technology, Hangzhou 310023, China
| | - Binju Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Zexing Cao
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
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4
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Jacquet P, Billot R, Shimon A, Hoekstra N, Bergonzi C, Jenks A, Chabrière E, Daudé D, Elias MH. Changes in Active Site Loop Conformation Relate to the Transition toward a Novel Enzymatic Activity. JACS AU 2024; 4:1941-1953. [PMID: 38818068 PMCID: PMC11134384 DOI: 10.1021/jacsau.4c00179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 04/11/2024] [Accepted: 04/12/2024] [Indexed: 06/01/2024]
Abstract
Enzymatic promiscuity, the ability of enzymes to catalyze multiple, distinct chemical reactions, has been well documented and is hypothesized to be a major driver of the emergence of new enzymatic functions. Yet, the molecular mechanisms involved in the transition from one activity to another remain debated and elusive. Here, we evaluated the redesign of the active site binding cleft of lactonase SsoPox using structure-based design and combinatorial libraries. We created variants with largely improved catalytic abilities against phosphotriesters, the best ones being >1000-fold better compared to the wild-type enzyme. The observed shifts in activity specificity are large, and some variants completely lost their initial activity. The selected combinations of mutations have considerably reshaped the active site cavity via side chain changes but mostly through large rearrangements of the active site loops and changes to their conformations, as revealed by a suite of crystal structures. This suggests that a specific active site loop configuration is critical to the lactonase activity. Interestingly, analysis of high-resolution structures hints at the potential role of conformational sampling and its directionality in defining the enzyme activity profile.
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Affiliation(s)
| | - Raphaël Billot
- Gene&GreenTK, 19-21 Bd Jean Moulin, Marseille 13005, France
| | - Amir Shimon
- Biotechnology
Institute, University of Minnesota, St. Paul, Minnesota 55108, United States
| | - Nathan Hoekstra
- Biotechnology
Institute, University of Minnesota, St. Paul, Minnesota 55108, United States
| | - Céline Bergonzi
- Gene&GreenTK, 19-21 Bd Jean Moulin, Marseille 13005, France
- Biotechnology
Institute, University of Minnesota, St. Paul, Minnesota 55108, United States
| | - Anthony Jenks
- Department
of Biochemistry, Molecular Biology and Biophysics & Biotechnology
Institute, University of Minnesota, St. Paul, Minnesota 55108, United States
| | - Eric Chabrière
- Gene&GreenTK, 19-21 Bd Jean Moulin, Marseille 13005, France
- Aix
Marseille University, IRD, APHM, MEPHI, IHU Méditerranée Infection, Marseille 13005, France
| | - David Daudé
- Gene&GreenTK, 19-21 Bd Jean Moulin, Marseille 13005, France
| | - Mikael H. Elias
- Biotechnology
Institute, University of Minnesota, St. Paul, Minnesota 55108, United States
- Department
of Biochemistry, Molecular Biology and Biophysics & Biotechnology
Institute, University of Minnesota, St. Paul, Minnesota 55108, United States
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5
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Lane TR, Koebel D, Lucas E, Moyer R, Ekins S. In Vitro Characterization and Rescue of VX Metabolism in Human Liver Microsomes. Drug Metab Dispos 2024; 52:574-579. [PMID: 38594080 DOI: 10.1124/dmd.124.001695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Revised: 04/03/2024] [Accepted: 04/05/2024] [Indexed: 04/11/2024] Open
Abstract
Venomous agent X (VX) is an organophosphate acetylcholinesterase (AChE) inhibitor, and although it is one of the most toxic AChE inhibitors known, the extent of metabolism in humans is not currently well understood. The known metabolism in humans is limited to the metabolite identification from a single victim of the Osaka poisoning in 1994, which allowed for the identification of several metabolic products. VX has been reported to be metabolized in vitro by paraoxonase-1 and phosphotriesterase, although their binding constants are many orders of magnitude above the LD50, suggesting limited physiologic relevance. Using incubation with human liver microsomes (HLMs), we have now characterized the metabolism of VX and the formation of multiple metabolites as well as identified a Food and Drug Administration-approved drug [ethylenediaminetetraacetic acid (EDTA)] that enhances the metabolic rate. HLM incubation alone shows a pronounced increase in the metabolism of VX compared with buffer, suggesting that cytochrome P450-mediated metabolism of VX is occurring. We identified a biphasic decay with two distinct rates of metabolism. The enhancement of VX metabolism in multiple buffers was assessed to attempt to mitigate the effect of hydrolysis rates. The formation of VX metabolites was shown to be shifted with HLMs, suggesting a pathway enhancement over simple hydrolysis. Additionally, our investigation of hydrolysis rates in various common buffers used in biologic assays discovered dramatic differences in VX stability. The new human in vitro VX metabolic data reported points to a potential in vivo treatment strategy (EDTA) for rescue in individuals that are poisoned though enhancement of metabolism alongside existing treatments. SIGNIFICANCE STATEMENT: Venomous agent X (VX) is a potent acetylcholinesterase inhibitor and chemical weapon. To date, we do not possess a clear understanding of its metabolism in humans that would assist us in treating those exposed to it. This study now describes the human liver microsomal metabolism of VX and identifies ethylenediaminetetraacetic acid, which appears to enhance the rate of metabolism. This may provide a potential treatment option for human VX poisoning.
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Affiliation(s)
- Thomas R Lane
- Collaborations Pharmaceuticals, Inc., Raleigh, North Carolina (T.R.L., S.E.) and Battelle Memorial Institute, Columbus, Ohio (D.K., E.L., R.M.)
| | - David Koebel
- Collaborations Pharmaceuticals, Inc., Raleigh, North Carolina (T.R.L., S.E.) and Battelle Memorial Institute, Columbus, Ohio (D.K., E.L., R.M.)
| | - Eric Lucas
- Collaborations Pharmaceuticals, Inc., Raleigh, North Carolina (T.R.L., S.E.) and Battelle Memorial Institute, Columbus, Ohio (D.K., E.L., R.M.)
| | - Robert Moyer
- Collaborations Pharmaceuticals, Inc., Raleigh, North Carolina (T.R.L., S.E.) and Battelle Memorial Institute, Columbus, Ohio (D.K., E.L., R.M.)
| | - Sean Ekins
- Collaborations Pharmaceuticals, Inc., Raleigh, North Carolina (T.R.L., S.E.) and Battelle Memorial Institute, Columbus, Ohio (D.K., E.L., R.M.)
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6
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Dym O, Aggarwal N, Ashani Y, Leader H, Albeck S, Unger T, Hamer-Rogotner S, Silman I, Tawfik DS, Sussman JL. The impact of molecular variants, crystallization conditions and the space group on ligand-protein complexes: a case study on bacterial phosphotriesterase. Acta Crystallogr D Struct Biol 2023; 79:992-1009. [PMID: 37860961 PMCID: PMC10619419 DOI: 10.1107/s2059798323007672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 09/03/2023] [Indexed: 10/21/2023] Open
Abstract
A bacterial phosphotriesterase was employed as an experimental paradigm to examine the effects of multiple factors, such as the molecular constructs, the ligands used during protein expression and purification, the crystallization conditions and the space group, on the visualization of molecular complexes of ligands with a target enzyme. In this case, the ligands used were organophosphates that are fragments of the nerve agents and insecticides on which the enzyme acts as a bioscavenger. 12 crystal structures of various phosphotriesterase constructs obtained by directed evolution were analyzed, with resolutions of up to 1.38 Å. Both apo forms and holo forms, complexed with the organophosphate ligands, were studied. Crystals obtained from three different crystallization conditions, crystallized in four space groups, with and without N-terminal tags, were utilized to investigate the impact of these factors on visualizing the organophosphate complexes of the enzyme. The study revealed that the tags used for protein expression can lodge in the active site and hinder ligand binding. Furthermore, the space group in which the protein crystallizes can significantly impact the visualization of bound ligands. It was also observed that the crystallization precipitants can compete with, and even preclude, ligand binding, leading to false positives or to the incorrect identification of lead drug candidates. One of the co-crystallization conditions enabled the definition of the spaces that accommodate the substituents attached to the P atom of several products of organophosphate substrates after detachment of the leaving group. The crystal structures of the complexes of phosphotriesterase with the organophosphate products reveal similar short interaction distances of the two partially charged O atoms of the P-O bonds with the exposed β-Zn2+ ion and the buried α-Zn2+ ion. This suggests that both Zn2+ ions have a role in stabilizing the transition state for substrate hydrolysis. Overall, this study provides valuable insights into the challenges and considerations involved in studying the crystal structures of ligand-protein complexes, highlighting the importance of careful experimental design and rigorous data analysis in ensuring the accuracy and reliability of the resulting phosphotriesterase-organophosphate structures.
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Affiliation(s)
- Orly Dym
- Department of Life Sciences Core Facilities, Weizmann Institute of Science, Rehovot, Israel
| | - Nidhi Aggarwal
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Yacov Ashani
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Haim Leader
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Shira Albeck
- Department of Life Sciences Core Facilities, Weizmann Institute of Science, Rehovot, Israel
| | - Tamar Unger
- Department of Life Sciences Core Facilities, Weizmann Institute of Science, Rehovot, Israel
| | - Shelly Hamer-Rogotner
- Department of Life Sciences Core Facilities, Weizmann Institute of Science, Rehovot, Israel
| | - Israel Silman
- Department of Brain Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Dan S. Tawfik
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Joel L. Sussman
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, Israel
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7
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Jacquet P, Billot R, Shimon A, Hoekstra N, Bergonzi C, Jenks A, Chabrière E, Daudé D, Elias MH. Changes in Active Site Loop Conformation Relate to the Transition toward a Novel Enzymatic Activity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.22.541809. [PMID: 37292757 PMCID: PMC10245850 DOI: 10.1101/2023.05.22.541809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Enzymatic promiscuity, the ability of enzymes to catalyze multiple, distinct chemical reactions, has been well documented and is hypothesized to be a major driver for the emergence of new enzymatic functions. Yet, the molecular mechanisms involved in the transition from one activity to another remain debated and elusive. Here, we evaluated the redesign of the active site binding cleft of the lactonase SsoPox using structure-based design and combinatorial libraries. We created variants with largely improved catalytic abilities against phosphotriesters, the best ones being > 1,000-fold better compared to the wild-type enzyme. The observed shifts in activity specificity are large, ~1,000,000-fold and beyond, since some variants completely lost their initial activity. The selected combinations of mutations have considerably reshaped the active site cavity via side chain changes but mostly through large rearrangements of the active site loops, as revealed by a suite of crystal structures. This suggests that specific active site loop configuration is critical to the lactonase activity. Interestingly, analysis of high-resolution structures hints at the potential role of conformational sampling and its directionality in defining an enzyme activity profile.
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Affiliation(s)
- Pauline Jacquet
- Gene&GreenTK, 19-21 Bd Jean Moulin, 13005, Marseille, France
| | - Raphaël Billot
- Gene&GreenTK, 19-21 Bd Jean Moulin, 13005, Marseille, France
| | - Amir Shimon
- University of Minnesota, Department of Biochemistry, Molecular Biology and Biophysics & Biotechnology Institute, St. Paul, MN, 55108, USA
| | - Nathan Hoekstra
- University of Minnesota, Department of Biochemistry, Molecular Biology and Biophysics & Biotechnology Institute, St. Paul, MN, 55108, USA
| | - Céline Bergonzi
- University of Minnesota, Department of Biochemistry, Molecular Biology and Biophysics & Biotechnology Institute, St. Paul, MN, 55108, USA
| | - Anthony Jenks
- University of Minnesota, Department of Biochemistry, Molecular Biology and Biophysics & Biotechnology Institute, St. Paul, MN, 55108, USA
| | - Eric Chabrière
- Gene&GreenTK, 19-21 Bd Jean Moulin, 13005, Marseille, France
- Aix Marseille University, IRD, APHM, MEPHI, IHU Méditerranée Infection, Marseille 13005, France
| | - David Daudé
- Gene&GreenTK, 19-21 Bd Jean Moulin, 13005, Marseille, France
| | - Mikael H. Elias
- University of Minnesota, Department of Biochemistry, Molecular Biology and Biophysics & Biotechnology Institute, St. Paul, MN, 55108, USA
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8
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Mali H, Shah C, Raghunandan BH, Prajapati AS, Patel DH, Trivedi U, Subramanian RB. Organophosphate pesticides an emerging environmental contaminant: Pollution, toxicity, bioremediation progress, and remaining challenges. J Environ Sci (China) 2023; 127:234-250. [PMID: 36522056 DOI: 10.1016/j.jes.2022.04.023] [Citation(s) in RCA: 64] [Impact Index Per Article: 64.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Revised: 04/19/2022] [Accepted: 04/19/2022] [Indexed: 06/17/2023]
Abstract
Organophosphates (OPs) are an integral part of modern agriculture; however, due to overexploitation, OPs pesticides residues are leaching and accumulating in the soil, and groundwater contaminated terrestrial and aquatic food webs. Acute exposure to OPs could produce toxicity in insects, plants, animals, and humans. OPs are known for covalent inhibition of acetylcholinesterase enzyme in pests and terrestrial/aquatic organisms, leading to nervous, respiratory, reproductive, and hepatic abnormalities. OPs pesticides also disrupt the growth-promoting machinery in plants by inhibiting key enzymes, permeability, and trans-cuticular diffusion, which is crucial for plant growth. Excessive use of OPs, directly/indirectly affecting human/environmental health, raise a thoughtful global concern. Developing a safe, reliable, economical, and eco-friendly methods for removing OPs pesticides from the environment is thus necessary. Bioremediation techniques coupled with microbes or microbial-biocatalysts are emerging as promising antidotes for OPs pesticides. Here, we comprehensively review the current scenario of OPs pollution, their toxicity (at a molecular level), and the recent advancements in biotechnology (modified biocatalytic systems) for detection, decontamination, and bioremediation of OP-pesticides in polluted environments. Furthermore, the review focuses on onsite applications of OPs degrading enzymes (immobilizations/biosensors/others), and it also highlights remaining challenges with future approaches.
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Affiliation(s)
- Himanshu Mali
- P. G. Department of Biosciences, UGC-Centre of Advanced Studies, Satellite Campus, Sardar Patel University, Sardar Patel Maidan, Bakrol-Vadtal Road, Bakrol 388 315, Gujarat, India
| | - Chandni Shah
- P. G. Department of Biosciences, UGC-Centre of Advanced Studies, Satellite Campus, Sardar Patel University, Sardar Patel Maidan, Bakrol-Vadtal Road, Bakrol 388 315, Gujarat, India
| | - B H Raghunandan
- P. G. Department of Biosciences, UGC-Centre of Advanced Studies, Satellite Campus, Sardar Patel University, Sardar Patel Maidan, Bakrol-Vadtal Road, Bakrol 388 315, Gujarat, India
| | - Anil S Prajapati
- P. G. Department of Biosciences, UGC-Centre of Advanced Studies, Satellite Campus, Sardar Patel University, Sardar Patel Maidan, Bakrol-Vadtal Road, Bakrol 388 315, Gujarat, India
| | - Darshan H Patel
- Charotar Institute of Paramedical Sciences, Charotar University of Science and Technology, (CHARUSAT), Changa 388421, Gujarat, India
| | - Ujjval Trivedi
- P. G. Department of Biosciences, UGC-Centre of Advanced Studies, Satellite Campus, Sardar Patel University, Sardar Patel Maidan, Bakrol-Vadtal Road, Bakrol 388 315, Gujarat, India
| | - R B Subramanian
- P. G. Department of Biosciences, UGC-Centre of Advanced Studies, Satellite Campus, Sardar Patel University, Sardar Patel Maidan, Bakrol-Vadtal Road, Bakrol 388 315, Gujarat, India.
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9
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Job L, Köhler A, Eichinger A, Testanera M, Escher B, Worek F, Skerra A. Structural and Functional Analysis of a Highly Active Designed Phosphotriesterase for the Detoxification of Organophosphate Nerve Agents Reveals an Unpredicted Conformation of the Active Site Loop. Biochemistry 2023; 62:942-955. [PMID: 36752589 DOI: 10.1021/acs.biochem.2c00666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Neurotoxic organophosphorus compounds (OPs) pose a severe threat if misused in military conflicts or by terrorists. Administration of a hydrolytic enzyme that can decompose the circulating nerve agent into non-toxic metabolites in vivo offers a potential treatment. A promising candidate is the homo-dimeric phosphotriesterase originating from the bacterium Brevundimonas diminuta (BdPTE), which has been subject to several rational and combinatorial protein design studies. A series of engineered versions with much improved catalytic efficiencies toward medically relevant nerve agents was described, carrying up to 22 mutations per enzyme subunit. To provide a basis for further rational design, we have determined the crystal structure of the highly active variant 10-2-C3(C59V/C227V)─stabilized against oxidation by substitution of two unpaired Cys residues─in complex with a substrate analogue at 1.5 Å resolution. Unexpectedly, the long loop segment (residues 253-276) that covers the active site shows a totally new conformation, with drastic structural deviations up to 19 Å, which was neither predicted in any of the preceding protein design studies nor seen in previous crystallographic analyses of less far evolved enzyme versions. Inspired by this structural insight, additional amino acid exchanges were introduced and their effects on protein stability as well as on the catalytic efficiency toward several neurotoxic OPs were investigated. Somewhat surprisingly, our results suggest that the presently available engineered version of BdPTE, in spite of its design on the basis of partly false structural assumptions, constitutes a fairly optimized enzyme for the detoxification of relevant OP nerve agents.
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Affiliation(s)
- Laura Job
- Lehrstuhl für Biologische Chemie, Technische Universität München, Emil-Erlenmeyer-Forum 5, 85354 Freising, Germany
| | - Anja Köhler
- Lehrstuhl für Biologische Chemie, Technische Universität München, Emil-Erlenmeyer-Forum 5, 85354 Freising, Germany.,Bundeswehr Institut für Pharmakologie und Toxikologie, Neuherbergstr. 11, 80937 München, Germany
| | - Andreas Eichinger
- Lehrstuhl für Biologische Chemie, Technische Universität München, Emil-Erlenmeyer-Forum 5, 85354 Freising, Germany
| | - Mauricio Testanera
- Lehrstuhl für Biologische Chemie, Technische Universität München, Emil-Erlenmeyer-Forum 5, 85354 Freising, Germany
| | - Benjamin Escher
- Lehrstuhl für Biologische Chemie, Technische Universität München, Emil-Erlenmeyer-Forum 5, 85354 Freising, Germany
| | - Franz Worek
- Bundeswehr Institut für Pharmakologie und Toxikologie, Neuherbergstr. 11, 80937 München, Germany
| | - Arne Skerra
- Lehrstuhl für Biologische Chemie, Technische Universität München, Emil-Erlenmeyer-Forum 5, 85354 Freising, Germany
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10
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Job L, Köhler A, Testanera M, Escher B, Worek F, Skerra A. Engineering of a phosphotriesterase with improved stability and enhanced activity for detoxification of the pesticide metabolite malaoxon. Protein Eng Des Sel 2023; 36:gzad020. [PMID: 37941439 DOI: 10.1093/protein/gzad020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 10/30/2023] [Accepted: 11/03/2023] [Indexed: 11/10/2023] Open
Abstract
Organophosphorus (OP) pesticides are still widely applied but pose a severe toxicological threat if misused. For in vivo detoxification, the application of hydrolytic enzymes potentially offers a promising treatment. A well-studied example is the phosphotriesterase of Brevundimonas diminuta (BdPTE). Whereas wild-type BdPTE can hydrolyse pesticides like paraoxon, chlorpyrifos-oxon and mevinphos with high catalytic efficiencies, kcat/KM >2 × 107 M-1 min-1, degradation of malaoxon is unsatisfactory (kcat/KM ≈ 1 × 104 M-1 min-1). Here, we report the rational engineering of BdPTE mutants with improved properties and their efficient production in Escherichia coli. As result, the mutant BdPTE(VRNVVLARY) exhibits 37-fold faster malaoxon hydrolysis (kcat/KM = 4.6 × 105 M-1 min-1), together with enhanced expression yield, improved thermal stability and reduced susceptibility to oxidation. Therefore, this BdPTE mutant constitutes a powerful candidate to develop a biocatalytic antidote for the detoxification of this common pesticide metabolite as well as related OP compounds.
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Affiliation(s)
- Laura Job
- Lehrstuhl für Biologische Chemie, Technische Universität München, Emil-Erlenmeyer-Forum 5, 85354 Freising, Germany
| | - Anja Köhler
- Lehrstuhl für Biologische Chemie, Technische Universität München, Emil-Erlenmeyer-Forum 5, 85354 Freising, Germany
- Institut für Pharmakologie und Toxikologie der Bundeswehr, Neuherbergstr, 11, 80937 München, Germany
| | - Mauricio Testanera
- Lehrstuhl für Biologische Chemie, Technische Universität München, Emil-Erlenmeyer-Forum 5, 85354 Freising, Germany
| | - Benjamin Escher
- Lehrstuhl für Biologische Chemie, Technische Universität München, Emil-Erlenmeyer-Forum 5, 85354 Freising, Germany
| | - Franz Worek
- Institut für Pharmakologie und Toxikologie der Bundeswehr, Neuherbergstr, 11, 80937 München, Germany
| | - Arne Skerra
- Lehrstuhl für Biologische Chemie, Technische Universität München, Emil-Erlenmeyer-Forum 5, 85354 Freising, Germany
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11
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Schnettler JD, Klein OJ, Kaminski TS, Colin PY, Hollfelder F. Ultrahigh-Throughput Directed Evolution of a Metal-Free α/β-Hydrolase with a Cys-His-Asp Triad into an Efficient Phosphotriesterase. J Am Chem Soc 2023; 145:1083-1096. [PMID: 36583539 PMCID: PMC9853848 DOI: 10.1021/jacs.2c10673] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Finding new mechanistic solutions for biocatalytic challenges is key in the evolutionary adaptation of enzymes, as well as in devising new catalysts. The recent release of man-made substances into the environment provides a dynamic testing ground for observing biocatalytic innovation at play. Phosphate triesters, used as pesticides, have only recently been introduced into the environment, where they have no natural counterpart. Enzymes have rapidly evolved to hydrolyze phosphate triesters in response to this challenge, converging onto the same mechanistic solution, which requires bivalent cations as a cofactor for catalysis. In contrast, the previously identified metagenomic promiscuous hydrolase P91, a homologue of acetylcholinesterase, achieves slow phosphotriester hydrolysis mediated by a metal-independent Cys-His-Asp triad. Here, we probe the evolvability of this new catalytic motif by subjecting P91 to directed evolution. By combining a focused library approach with the ultrahigh throughput of droplet microfluidics, we increase P91's activity by a factor of ≈360 (to a kcat/KM of ≈7 × 105 M-1 s-1) in only two rounds of evolution, rivaling the catalytic efficiencies of naturally evolved, metal-dependent phosphotriesterases. Unlike its homologue acetylcholinesterase, P91 does not suffer suicide inhibition; instead, fast dephosphorylation rates make the formation of the covalent adduct rather than its hydrolysis rate-limiting. This step is improved by directed evolution, with intermediate formation accelerated by 2 orders of magnitude. Combining focused, combinatorial libraries with the ultrahigh throughput of droplet microfluidics can be leveraged to identify and enhance mechanistic strategies that have not reached high efficiency in nature, resulting in alternative reagents with novel catalytic machineries.
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Affiliation(s)
- J David Schnettler
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, United Kingdom
| | - Oskar James Klein
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, United Kingdom
| | - Tomasz S Kaminski
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, United Kingdom
| | - Pierre-Yves Colin
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, United Kingdom
| | - Florian Hollfelder
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, United Kingdom
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12
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Kulakova AM, Mulashkina TI, Nemukhin AV, Khrenova MG. Influence of the leaving group on the mechanism of hydrolysis of organophosphorus compounds by phosphotriesterase from bacterium Pseudomonas diminuta. Russ Chem Bull 2022. [DOI: 10.1007/s11172-022-3491-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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13
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Fu Y, Fan F, Wang B, Cao Z. Water-Regulated Mechanisms for Degradation of Pesticides Paraoxon and Parathion by Phosphotriesterase: Insight from QM/MM and MD Simulations. Chem Asian J 2022; 17:e202200439. [PMID: 35586954 DOI: 10.1002/asia.202200439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 05/12/2022] [Indexed: 11/06/2022]
Abstract
The enzymatic degradation of pesticides paraoxon (PON) and parathion (PIN) by phosphotriesterase (PTE) has been investigated by QM/MM calculations and MD simulations. In the PTE-PON complex, Zn α and Zn β in the active site are five- and six-coordinated, respectively, while both zinc ions are six coordinated with the Zn α -bound water molecule (WT1) for the PTE-PIN system. The hydrolytic reactions for PON and PIN are respectively driven by the nucleophilic attack of the bridging-OH - and the Zn α -bound water molecule on the phosphorus center of substrate, and the two-step hydrolytic process is predicted to be the rate-limiting step with the energy spans of 13.8 and 14.4 kcal/mol for PON and PIN, respectively. The computational studies reveal that the presence of the Zn α -bound water molecule depends on the structural feature of substrates characterized by P=O and P=S, which determines the hydrolytic mechanism and efficiency for the degradation of organophosphorus pesticides by PTE.
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Affiliation(s)
- Yuzhuang Fu
- Xiamen University, Department of Chemistry, CHINA
| | - Fangfang Fan
- Zhejiang University of Science and Technology, School of Biological and Chemical Engineering, CHINA
| | - Binju Wang
- Xiamen University, Department of Chemistry, CHINA
| | - Zexing Cao
- Xiamen University, Department of Chemistry, Si Ming Nan Lu, 361005, Xiamen, CHINA
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14
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Mali H, Shah C, Patel DH, Trivedi U, Subramanian RB. Bio-catalytic system of metallohydrolases for remediation of neurotoxin organophosphates and applications with a future vision. J Inorg Biochem 2022; 231:111771. [DOI: 10.1016/j.jinorgbio.2022.111771] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Revised: 02/15/2022] [Accepted: 02/19/2022] [Indexed: 12/29/2022]
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15
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Fan F, Zheng YC, Fu Y, Zhang Y, Zheng H, Lyu C, Chen L, Huang J, Cao Z. QM/MM and MM MD simulations on decontamination of the V-type nerve agent VX by phosphotriesterase: Toward a comprehensive understanding of steroselectivity and activity. Phys Chem Chem Phys 2022; 24:10933-10943. [DOI: 10.1039/d2cp00773h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Due to deadly toxicity and high environmental stability of the nerve agent VX, an efficient decontamination approach is desperately needed in tackling its severe threat to human secu-rity. The enzymatic...
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16
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Bigley AN, Harvey SP, Narindoshvili T, Raushel FM. Substrate Analogues for the Enzyme-Catalyzed Detoxification of the Organophosphate Nerve Agents-Sarin, Soman, and Cyclosarin. Biochemistry 2021; 60:2875-2887. [PMID: 34494832 DOI: 10.1021/acs.biochem.1c00361] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The G-type nerve agents, sarin (GB), soman (GD), and cyclosarin (GF), are among the most toxic compounds known. Much progress has been made in evolving the enzyme phosphotriesterase (PTE) from Pseudomonas diminuta for the decontamination of the G-agents; however, the extreme toxicity of the G-agents makes the use of substrate analogues necessary. Typical analogues utilize a chromogenic leaving group to facilitate high-throughput screening, and substitution of an O-methyl for the P-methyl group found in the G-agents, in an effort to reduce toxicity. Till date, there has been no systematic evaluation of the effects of these substitutions on catalytic activity, and the presumed reduction in toxicity has not been tested. A series of 21 G-agent analogues, including all combinations of O-methyl, p-nitrophenyl, and thiophosphate substitutions, have been synthesized and evaluated for their ability to unveil the stereoselectivity and catalytic activity of PTE variants against the authentic G-type nerve agents. The potential toxicity of these analogues was evaluated by measuring the rate of inactivation of acetylcholinesterase (AChE). All of the substitutions reduced inactivation of AChE by more than 100-fold, with the most effective being the thiophosphate analogues, which reduced the rate of inactivation by about 4-5 orders of magnitude. The analogues were found to reliably predict changes in catalytic activity and stereoselectivity of the PTE variants and led to the identification of the BHR-30 variant, which has no apparent stereoselectivity against GD and a kcat/Km of 1.4 × 106, making it the most efficient enzyme for GD decontamination reported till date.
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Affiliation(s)
- Andrew N Bigley
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Steven P Harvey
- US Army DEVCOM-CBC, FCDD-CBR-CC E3400, 5183 Blackhawk Rd. Aberdeen Proving Ground, Aberdeen, Maryland 21010, United States
| | - Tamari Narindoshvili
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Frank M Raushel
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States.,Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas 7784, United States
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17
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Immobilization of Mutant Phosphotriesterase on Fuller’s Earth Enhanced the Stability of the Enzyme. Catalysts 2021. [DOI: 10.3390/catal11080983] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Immobilization is a method for making an enzyme more robust in the environment, especially in terms of its stability and reusability. A mutant phosphotriesterase (YT PTE) isolated from Pseudomonas dimunita has been reported to have high proficiency in hydrolyzing the Sp and Rp-enantiomers of organophosphate chromophoric analogs and therefore has great potential as a decontamination agent and biosensor. This work aims to investigate the feasibility of using Fuller’s earth (FE) as a YT PTE immobilization support and characterize its biochemical features after immobilization. The immobilized YT PTE was found to show improvement in thermal stability with a half-life of 24 h compared to that of the free enzyme, which was only 8 h. The stability of the immobilized YT PTE allowed storage for up to 4 months and reuse for up to 6 times. The immobilized YT PTE showed high tolerance against all tested metal ions, Tween 40 and 80 surfactants and inorganic solvents. These findings showed that the immobilized YT PTE became more robust for use especially with regards to its stability and reusability. These features would enhance the future applicability of this enzyme as a decontamination agent and its use in other suitable industrial applications.
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18
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Leverant CJ, Priest CW, Greathouse JA, Kinnan MK, Rempe SB. Quantum Calculations of VX Ammonolysis and Hydrolysis Pathways via Hydrated Lithium Nitride. Int J Mol Sci 2021; 22:ijms22168653. [PMID: 34445355 PMCID: PMC8395404 DOI: 10.3390/ijms22168653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/29/2021] [Accepted: 08/02/2021] [Indexed: 11/16/2022] Open
Abstract
Recently, lithium nitride (Li3N) has been proposed as a chemical warfare agent (CWA) neutralization reagent for its ability to produce nucleophilic ammonia molecules and hydroxide ions in aqueous solution. Quantum chemical calculations can provide insight into the Li3N neutralization process that has been studied experimentally. Here, we calculate reaction-free energies associated with the Li3N-based neutralization of the CWA VX using quantum chemical density functional theory and ab initio methods. We find that alkaline hydrolysis is more favorable to either ammonolysis or neutral hydrolysis for initial P-S and P-O bond cleavages. Reaction-free energies of subsequent reactions are calculated to determine the full reaction pathway. Notably, products predicted from favorable reactions have been identified in previous experiments.
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Affiliation(s)
- Calen J. Leverant
- Sandia National Laboratories, Albuquerque, NM 87185, USA; (C.J.L.); (C.W.P.); (J.A.G.); (M.K.K.)
- Department of Chemical Engineering, University of Florida, Gainesville, FL 32611, USA
| | - Chad W. Priest
- Sandia National Laboratories, Albuquerque, NM 87185, USA; (C.J.L.); (C.W.P.); (J.A.G.); (M.K.K.)
| | - Jeffery A. Greathouse
- Sandia National Laboratories, Albuquerque, NM 87185, USA; (C.J.L.); (C.W.P.); (J.A.G.); (M.K.K.)
| | - Mark K. Kinnan
- Sandia National Laboratories, Albuquerque, NM 87185, USA; (C.J.L.); (C.W.P.); (J.A.G.); (M.K.K.)
| | - Susan B. Rempe
- Sandia National Laboratories, Albuquerque, NM 87185, USA; (C.J.L.); (C.W.P.); (J.A.G.); (M.K.K.)
- Correspondence:
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19
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Köhler A, Escher B, Job L, Koller M, Thiermann H, Skerra A, Worek F. Catalytic activity and stereoselectivity of engineered phosphotriesterases towards structurally different nerve agents in vitro. Arch Toxicol 2021; 95:2815-2823. [PMID: 34160649 PMCID: PMC8298220 DOI: 10.1007/s00204-021-03094-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 06/15/2021] [Indexed: 12/20/2022]
Abstract
Highly toxic organophosphorus nerve agents, especially the extremely stable and persistent V-type agents such as VX, still pose a threat to the human population and require effective medical countermeasures. Engineered mutants of the Brevundimonas diminuta phosphotriesterase (BdPTE) exhibit enhanced catalytic activities and have demonstrated detoxification in animal models, however, substrate specificity and fast plasma clearance limit their medical applicability. To allow better assessment of their substrate profiles, we have thoroughly investigated the catalytic efficacies of five BdPTE mutants with 17 different nerve agents using an AChE inhibition assay. In addition, we studied one BdPTE version that was fused with structurally disordered PAS polypeptides to enable delayed plasma clearance and one bispecific BdPTE with broadened substrate spectrum composed of two functionally distinct subunits connected by a PAS linker. Measured kcat/KM values were as high as 6.5 and 1.5 × 108 M-1 min-1 with G- and V-agents, respectively. Furthermore, the stereoselective degradation of VX enantiomers by the PASylated BdPTE-4 and the bispecific BdPTE-7 were investigated by chiral LC-MS/MS, resulting in a several fold faster hydrolysis of the more toxic P(-) VX stereoisomer compared to P(+) VX. In conclusion, the newly developed enzymes BdPTE-4 and BdPTE-7 have shown high catalytic efficacy towards structurally different nerve agents and stereoselectivity towards the toxic P(-) VX enantiomer in vitro and offer promise for use as bioscavengers in vivo.
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Affiliation(s)
- Anja Köhler
- Institut für Pharmakologie und Toxikologie der Bundeswehr, 80937, Munich, Germany
- Lehrstuhl für Biologische Chemie, Technische Universität München, 85354, Freising, Germany
| | - Benjamin Escher
- Lehrstuhl für Biologische Chemie, Technische Universität München, 85354, Freising, Germany
| | - Laura Job
- Lehrstuhl für Biologische Chemie, Technische Universität München, 85354, Freising, Germany
| | - Marianne Koller
- Institut für Pharmakologie und Toxikologie der Bundeswehr, 80937, Munich, Germany
| | - Horst Thiermann
- Institut für Pharmakologie und Toxikologie der Bundeswehr, 80937, Munich, Germany
| | - Arne Skerra
- Lehrstuhl für Biologische Chemie, Technische Universität München, 85354, Freising, Germany.
| | - Franz Worek
- Institut für Pharmakologie und Toxikologie der Bundeswehr, 80937, Munich, Germany.
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20
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Köhler A, Job L, Worek F, Skerra A. Inhibition of an organophosphate-detoxifying bacterial phosphotriesterase by albumin and plasma thiol components. Toxicol Lett 2021; 350:194-201. [PMID: 34303790 DOI: 10.1016/j.toxlet.2021.07.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 07/13/2021] [Accepted: 07/19/2021] [Indexed: 11/28/2022]
Abstract
The phosphotriesterase of the bacterium Brevundimonas diminuta (BdPTE) is a naturally occurring enzyme that catalyzes the hydrolysis of organophosphate (OP) nerve agents as well as pesticides and offers a potential treatment of corresponding intoxications. While BdPTE mutants with improved catalytic efficiencies against several OPs have been described, unexpectedly, less efficient breakdown of an OP was observed upon application in an animal model compared with in vitro measurements. Here, we describe detailed inhibition studies with the high-activity BdPTE mutant 10-2C3(C59M/C227A) by human plasma components, indicating that this enzyme is inhibited by serum albumin. The inhibitory activity is mediated by depletion of crucial zinc ions from the BdPTE active site, either via the known high-affinity zinc binding site of albumin or via chemical complex formation with its free thiol side chain at position Cys34. Albumin pre-charged with zinc ions or carrying a chemically blocked Cys34 side chain showed significantly reduced inhibitory activity; in fact, the combination of both measures completely abolished BdPTE inhibition. Consequently, the available zinc ion concentration in blood plays an important role for BdPTE activity in vivo and should be taken into account for therapeutic development and application of a catalytic OP scavenger.
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Affiliation(s)
- Anja Köhler
- Chair of Biological Chemistry, Technische Universität München, Emil-Erlenmeyer-Forum 5, 85354 Freising, Germany; Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstr. 11, 80937 Munich, Germany.
| | - Laura Job
- Chair of Biological Chemistry, Technische Universität München, Emil-Erlenmeyer-Forum 5, 85354 Freising, Germany.
| | - Franz Worek
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstr. 11, 80937 Munich, Germany.
| | - Arne Skerra
- Chair of Biological Chemistry, Technische Universität München, Emil-Erlenmeyer-Forum 5, 85354 Freising, Germany.
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21
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Poirier L, Jacquet P, Plener L, Masson P, Daudé D, Chabrière E. Organophosphorus poisoning in animals and enzymatic antidotes. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:25081-25106. [PMID: 29959732 DOI: 10.1007/s11356-018-2465-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 05/31/2018] [Indexed: 06/08/2023]
Abstract
Organophosphorus compounds (OPs) are neurotoxic molecules developed as pesticides and chemical warfare nerve agents (CWNAs). Most of them are covalent inhibitors of acetylcholinesterase (AChE), a key enzyme in nervous systems, and are therefore responsible for numerous poisonings around the world. Many animal models have been studied over the years in order to decipher the toxicity of OPs and to provide insights for therapeutic and decontamination purposes. Environmental impact on wild animal species has been analyzed to understand the consequences of OP uses in agriculture. In complement, various laboratory models, from invertebrates to aquatic organisms, rodents and primates, have been chosen to study chronic and acute toxicity as well as neurobehavioral impact, immune response, developmental disruption, and other pathological signs. Several decontamination approaches were developed to counteract the poisoning effects of OPs. Among these, enzyme-based strategies are particularly attractive as they allow efficient external decontamination without toxicity or environmental impact and may be of interest for treatment. Approaches using bioscavengers for prophylaxis, treatment, and external decontamination are emphasized and their potential is discussed in the light of toxicological observations from various animal models. The relevance of animal models, regarding their cholinergic system and the abundance of naturally protecting enzymes, is also discussed for better extrapolation of results to human.
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Affiliation(s)
- Laetitia Poirier
- IRD, APHM, MEPHI, IHU-Méditerranée Infection, Aix Marseille University, Marseille, France
| | - Pauline Jacquet
- Gene&GreenTK, 19-21 Boulevard Jean Moulin, 13005, Marseille, France
| | - Laure Plener
- Gene&GreenTK, 19-21 Boulevard Jean Moulin, 13005, Marseille, France
| | - Patrick Masson
- Neuropharmacology Laboratory, Kazan Federal University, Kazan, Russia
| | - David Daudé
- Gene&GreenTK, 19-21 Boulevard Jean Moulin, 13005, Marseille, France.
| | - Eric Chabrière
- IRD, APHM, MEPHI, IHU-Méditerranée Infection, Aix Marseille University, Marseille, France.
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22
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Goud KY, Sandhu SS, Teymourian H, Yin L, Tostado N, Raushel FM, Harvey SP, Moores LC, Wang J. Textile-based wearable solid-contact flexible fluoride sensor: Toward biodetection of G-type nerve agents. Biosens Bioelectron 2021; 182:113172. [PMID: 33812282 DOI: 10.1016/j.bios.2021.113172] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 02/07/2021] [Accepted: 03/13/2021] [Indexed: 12/12/2022]
Abstract
Rising global concerns posed by chemical and biological threat agents highlight the critical need to develop reliable strategies for the real-time detection of such threats. While wearable sensing technology is well suited to fulfill this task, the use of on-body devices for rapid and selective field identification of chemical agents is relatively a new area. This work describes a flexible printed textile-based solid-contact potentiometric sensor for the selective detection of fluoride anions liberated by the biocatalytic hydrolysis of fluorine-containing G-type nerve agents (such as sarin or soman). The newly developed solid-contact textile fluoride sensor relies on a fluoride-selective bis(fluorodioctylstannyl)methane ionophore to provide attractive analytical performance with near-Nernstian sensitivity and effective discrimination against common anions, along with excellent reversibility and repeatability for dynamically changing fluoride concentrations. By using stress-enduring printed inks and serpentine structures along with stretchable textile substrates, the resulting textile-based fluoride sensor exhibits robust mechanical resiliency under severe mechanical strains. Such realization of an effective textile-based fluoride-selective electrode allowed biosensing of the nerve-agent simulant diisopropyl fluorophosphate (DFP), in connection to immobilized organophosphorus acid anhydrolylase (OPAA) or organophosphorus hydrolase (OPH) enzymes. A user-friendly portable electronic module transmits data from the new textile-based potentiometric biosensor wirelessly to a nearby smartphone for alerting the wearer instantaneously about potential chemical threats. While expanding the scope of wearable solid-contact anion sensors, such a textile-based potentiometric fluoride electrode transducer offers particular promise for effective discrimination of G-type neurotoxins from organophosphate (OP) pesticides, toward specific field detection of these agents in diverse defense settings.
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Affiliation(s)
- K Yugender Goud
- Department of Nanoengineering, University of California, San Diego, La Jolla, CA, 92093, United States
| | - Samar S Sandhu
- Department of Nanoengineering, University of California, San Diego, La Jolla, CA, 92093, United States
| | - Hazhir Teymourian
- Department of Nanoengineering, University of California, San Diego, La Jolla, CA, 92093, United States
| | - Lu Yin
- Department of Nanoengineering, University of California, San Diego, La Jolla, CA, 92093, United States
| | - Nicholas Tostado
- Department of Nanoengineering, University of California, San Diego, La Jolla, CA, 92093, United States
| | - Frank M Raushel
- Department of Chemistry, Texas A&M University, College Station, TX, 77843, United States
| | - Steven P Harvey
- U.S. Army Combat Capabilities and Development Command-Chemical Biological Center (CCDC-CBC), Aberdeen Proving Ground, MD, 1010, United States
| | - Lee C Moores
- U.S. Army Engineer Research and Development Center, Installation and Operation Environment Program, Environmental Laboratory, 3909 Halls Ferry Road, Vicksburg, MS, 39180, United States
| | - Joseph Wang
- Department of Nanoengineering, University of California, San Diego, La Jolla, CA, 92093, United States.
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23
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Abdelrahman MS, Khattab TA, Kamel S. Hydrazone‐Based Supramolecular Organogel for Selective Chromogenic Detection of Organophosphorus Nerve Agent Mimic. ChemistrySelect 2021. [DOI: 10.1002/slct.202004850] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Meram S. Abdelrahman
- Dyeing Printing and Auxiliaries Department National Research Centre Cairo 12622 Egypt
| | - Tawfik A. Khattab
- Dyeing Printing and Auxiliaries Department National Research Centre Cairo 12622 Egypt
| | - Samir Kamel
- Chemical Industries Research Division National Research Centre Cairo 12622 Egypt
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24
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Facile Fabric Detoxification Treatment Method Using Microwave and Polyethyleneimine Against Nerve Gas Agents. Polymers (Basel) 2020; 12:polym12122861. [PMID: 33265928 PMCID: PMC7759827 DOI: 10.3390/polym12122861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 11/28/2020] [Accepted: 11/29/2020] [Indexed: 11/17/2022] Open
Abstract
Generally, detoxification fabrics are defined as fabrics that remove or inhibit the production of toxic compounds, especially chemical warfare agents such as nerve gas agents. They are usually prepared using a complicated and time-consuming method. This study suggests a facile treatment method for preparing detoxification fabrics against nerve gas agents using polyethyleneimine and microwave curing. The detoxification properties of polyethyleneimine and microwave-treated polypropylene nonwoven fabric were evaluated using diisopropylfluoro-phosphate, which is a nerve agent simulant. The treated polypropylene fabric decontaminated 53.6% of diisopropylfluorophosphate (DFP) in 2 h at 32 °C, and the half-life of DFP on the surface of the treated fabric was 122 min. The result indicates that the treated fabric can act as a basic organocatalyst for the DFP hydrolysis and has a shorter half-life owing to the large number of amine groups. Therefore, the facile treatment method has the potential for use in the preparation of detoxification fabrics.
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Chi MC, Liao TY, Lin MG, Lin LL, Wang TF. Expression and physicochemical characterization of an N-terminal polyhistidine-tagged phosphotriesterase from the soil bacterium Brevundimonas diminuta. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2020. [DOI: 10.1016/j.bcab.2020.101811] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Organophosphorus Nerve Agents: Types, Toxicity, and Treatments. J Toxicol 2020; 2020:3007984. [PMID: 33029136 PMCID: PMC7527902 DOI: 10.1155/2020/3007984] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 08/30/2020] [Accepted: 09/10/2020] [Indexed: 01/08/2023] Open
Abstract
Organophosphorus compounds are extensively used worldwide as pesticides which cause great hazards to human health. Nerve agents, a subcategory of the organophosphorus compounds, have been produced and used during wars, and they have also been used in terrorist activities. These compounds possess physiological threats by interacting and inhibiting acetylcholinesterase enzyme which leads to the cholinergic crisis. After a general introduction, this review elucidates the mechanisms underlying cholinergic and noncholinergic effects of organophosphorus compounds. The conceivable treatment strategies for organophosphate poisoning are different types of bioscavengers which include stoichiometric, catalytic, and pseudocatalytic. The current research on the promising treatments specifically the catalytic bioscavengers including several wild-type organophosphate hydrolases such as paraoxonase and phosphotriesterase, phosphotriesterase-like lactonase, methyl parathion hydrolase, organophosphate acid anhydrolase, diisopropyl fluorophosphatase, human triphosphate nucleotidohydrolase, and senescence marker protein has been widely discussed. Organophosphorus compounds are reported to be the nonphysiological substrate for many mammalian organophosphate hydrolysing enzymes; therefore, the efficiency of these enzymes toward these compounds is inadequate. Hence, studies have been conducted to create mutants with an enhanced rate of hydrolysis and high specificity. Several mutants have been created by applying directed molecular evolution and/or targeted mutagenesis, and catalytic efficiency has been characterized. Generally, organophosphorus compounds are chiral in nature. The development of mutant enzymes for providing superior stereoselective degradation of toxic organophosphorus compounds has also been widely accounted for in this review. Existing enzymes have shown limited efficiency; hence, more effective treatment strategies have also been critically analyzed.
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Katyal P, Chu S, Montclare JK. Enhancing organophosphate hydrolase efficacy via protein engineering and immobilization strategies. Ann N Y Acad Sci 2020; 1480:54-72. [PMID: 32814367 DOI: 10.1111/nyas.14451] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 06/21/2020] [Accepted: 07/07/2020] [Indexed: 01/30/2023]
Abstract
Organophosphorus compounds (OPs), developed as pesticides and chemical warfare agents, are extremely toxic chemicals that pose a public health risk. Of the different detoxification strategies, organophosphate-hydrolyzing enzymes have attracted much attention, providing a potential route for detoxifying those exposed to OPs. Phosphotriesterase (PTE), also known as organophosphate hydrolase (OPH), is one such enzyme that has been extensively studied as a catalytic bioscavenger. In this review, we will discuss the protein engineering of PTE aimed toward improving the activity and stability of the enzyme. In order to make enzyme utilization in OP detoxification more favorable, enzyme immobilization provides an effective means to increase enzyme activity and stability. Here, we present several such strategies that enhance the storage and operational stability of PTE/OPH.
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Affiliation(s)
- Priya Katyal
- Department of Chemical and Biomolecular Engineering, New York University, Tandon School of Engineering, Brooklyn, New York
| | - Stanley Chu
- Department of Chemical and Biomolecular Engineering, New York University, Tandon School of Engineering, Brooklyn, New York
| | - Jin Kim Montclare
- Department of Chemical and Biomolecular Engineering, New York University, Tandon School of Engineering, Brooklyn, New York.,Department of Radiology, New York University Langone Health, New York, New York.,Department of Biomaterials, New York University College of Dentistry, New York, New York.,Department of Chemistry, New York University, New York, New York
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28
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Theoretical Study of VX Hydrolysis Mechanism Catalyzed by Phosphotriesterase Mutant H254R. ChemistrySelect 2020. [DOI: 10.1002/slct.202002112] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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29
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Lang X, Hong X, Baker CA, Otto TC, Wheeldon I. Molecular binding scaffolds increase local substrate concentration enhancing the enzymatic hydrolysis of VX nerve agent. Biotechnol Bioeng 2020; 117:1970-1978. [PMID: 32239488 DOI: 10.1002/bit.27346] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 03/27/2020] [Accepted: 03/28/2020] [Indexed: 12/25/2022]
Abstract
Kinetic enhancement of organophosphate hydrolysis is a long-standing challenge in catalysis. For prophylactic treatment against organophosphate exposure, enzymatic hydrolysis needs to occur at high rates in the presence of low substrate concentrations and enzymatic activity should persist over days and weeks. Here, the conjugation of small DNA scaffolds was used to introduce substrate binding sites with micromolar affinity to VX, paraoxon, and methyl-parathion in close proximity to the enzyme phosphotriesterase (PTE). The result was a decrease in KM and increase in the rate at low substrate concentrations. An optimized system for paraoxon hydrolysis decreased KM by 11-fold, with a corresponding increase in second-order rate constant. The initial rates of VX and methyl-parathion hydrolysis were also increased by 3.1- and 6.7-fold, respectively. The designed scaffolds not only increased the local substrate concentration, but they also resulted in increased stability and PTE-DNA particle size tuning between 25 and ~150 nm. The scaffold engineering approach taken here is focused on altering the local chemical and physical microenvironment around the enzyme and is therefore compatible with active site engineering via combinatorial and computational approaches.
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Affiliation(s)
- Xuye Lang
- Chemical and Environmental Engineering Department, University of California, Riverside, California
| | - Xiao Hong
- Biochemistry Department, University of California, Riverside, California
| | - Cetara A Baker
- U.S. Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Aberdeen, Maryland
| | - Tamara C Otto
- U.S. Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Aberdeen, Maryland
| | - Ian Wheeldon
- Chemical and Environmental Engineering Department, University of California, Riverside, California.,Center for Industrial Biotechnology, University of California, Riverside, California
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30
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Koller M, Thiermann H, Worek F. Screening of chiral shift reagents suitable to generically separate the enantiomers of V-agents by 31P-NMR spectroscopy. Toxicol Lett 2020; 320:28-36. [PMID: 31805340 DOI: 10.1016/j.toxlet.2019.12.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 11/28/2019] [Accepted: 12/01/2019] [Indexed: 11/30/2022]
Abstract
Fourteen amino acids protected at the N-terminal and at their side chains were screened for resolving the enantiomers of V-agents by NMR. While none of the shift reagents tested showed really effective separation in proton NMR, two of them (BOC-Gln(Xan)-OH, 16, and Z-Arg(Z)2-OH), 21, with 16 superior to 21) were found suitable to separate the enantiomers of all V-agent homologues involved in the test by 31P-NMR. Molar ratios investigated were 1:0.5, 1:1, 1:1.5, 1:2, and 1:3 with the V-agent set to 1 throughout the experiments. All these ratios were more or less effective, but 1:3 was found to separate the V-agents the most reliable way. It is postulated that three chiral solvating molecules are then coordinated around the organophosphate: ion pair formation with the amino nitrogen of the V agent side chain, hydrogen bonding provided by the PO unit, and extension of coordination at the phosphorus atom itself. After chiral separation of VX by semi-preparative LC-MS the enantiomers were examined with both configurations of 16 releasing four different 31P NMR peaks which correspond to four different complexes: R-S3, R-R3, S-R3, and S-S3. Comparing these results with literature data it is assumed that (+)-VX corresponds to the RP configuration and (-)-VX to the SP-configuration.
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Affiliation(s)
- Marianne Koller
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstrasse 11, 80937, Munich, Germany.
| | - Horst Thiermann
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstrasse 11, 80937, Munich, Germany.
| | - Franz Worek
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstrasse 11, 80937, Munich, Germany.
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31
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Thakur M, Medintz IL, Walper SA. Enzymatic Bioremediation of Organophosphate Compounds-Progress and Remaining Challenges. Front Bioeng Biotechnol 2019; 7:289. [PMID: 31781549 PMCID: PMC6856225 DOI: 10.3389/fbioe.2019.00289] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 10/09/2019] [Indexed: 12/16/2022] Open
Abstract
Organophosphate compounds are ubiquitously employed as agricultural pesticides and maintained as chemical warfare agents by several nations. These compounds are highly toxic, show environmental persistence and accumulation, and contribute to numerous cases of poisoning and death each year. While their use as weapons of mass destruction is rare, these never fully disappear into obscurity as they continue to be tools of fear and control by governments and terrorist organizations. Beyond weaponization, their wide-scale dissemination as agricultural products has led to environmental accumulation and intoxication of soil and water across the globe. Therefore, there is a dire need for rapid and safe agents for environmental bioremediation, personal decontamination, and as therapeutic detoxicants. Organophosphate hydrolyzing enzymes are emerging as appealing targets to satisfy decontamination needs owing to their ability to hydrolyze both pesticides and nerve agents using biologically-derived materials safe for both the environment and the individual. As the release of genetically modified organisms is not widely accepted practice, researchers are exploring alternative strategies of organophosphate bioremediation that focus on cell-free enzyme systems. In this review, we first discuss several of the more prevalent organophosphorus hydrolyzing enzymes along with research and engineering efforts that have led to an enhancement in their activity, substrate tolerance, and stability. In the later half we focus on advances achieved through research focusing on enhancing the catalytic activity and stability of phosphotriesterase, a model organophosphate hydrolase, using various approaches such as nanoparticle display, DNA scaffolding, and outer membrane vesicle encapsulation.
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Affiliation(s)
- Meghna Thakur
- College of Science, George Mason University, Fairfax, VA, United States
| | - Igor L Medintz
- Center for Bio/Molecular Sciences, U.S. Naval Research Laboratory, Washington, DC, United States
| | - Scott A Walper
- Center for Bio/Molecular Sciences, U.S. Naval Research Laboratory, Washington, DC, United States
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32
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Zhang WH, Carter BM, Day GJ, Govan N, Jackson C, Perriman AW. Sequential Electrostatic Assembly of a Polymer Surfactant Corona Increases Activity of the Phosphotriesterase arPTE. Bioconjug Chem 2019; 30:2771-2776. [PMID: 31603664 DOI: 10.1021/acs.bioconjchem.9b00664] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
We present a new methodology for the generation of discrete molecularly dispersed enzyme-polymer-surfactant bioconjugates. Significantly, we demonstrate that >3-fold increase in the catalytic efficiency of the diffusion-limited phosphotriesterase arPTE can be achieved through sequential electrostatic addition of cationic and anionic polymer surfactants, respectively. Here, the polymer surfactants assemble on the surface of the enzyme via ion exchange to yield a compact corona. The observed rate enhancement is consistent with a mechanism whereby the polymer-surfactant corona gives rise to a decrease in the dielectric constant in the vicinity of the active site of the enzyme, accelerating the rate-determining product diffusion step. The facile methodology has significant potential for increasing the efficiency of enzymes and could therefore have a substantially positive impact for industrial enzymology.
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Affiliation(s)
- William H Zhang
- University of Bristol , School of Cellular and Molecular Medicine , Bristol BS8 1TD , United Kingdom
| | - Benjamin M Carter
- University of Bristol , School of Cellular and Molecular Medicine , Bristol BS8 1TD , United Kingdom
| | - Graham J Day
- University of Bristol , School of Cellular and Molecular Medicine , Bristol BS8 1TD , United Kingdom
| | - Norman Govan
- Defence Science and Technology Laboratory , Salisbury SP4 0JQ , United Kingdom
| | - Colin Jackson
- Australian National University , Research School of Chemistry , Canberra ACT 2601 , Australia
| | - Adam W Perriman
- University of Bristol , School of Cellular and Molecular Medicine , Bristol BS8 1TD , United Kingdom
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Abstract
The role of phosphotriesterase as an enzyme which is able to hydrolyze organophosphate compounds cannot be disputed. Contamination by organophosphate (OP) compounds in the environment is alarming, and even more worrying is the toxicity of this compound, which affects the nervous system. Thus, it is important to find a safer way to detoxify, detect and recuperate from the toxicity effects of this compound. Phosphotriesterases (PTEs) are mostly isolated from soil bacteria and are classified as metalloenzymes or metal-dependent enzymes that contain bimetals at the active site. There are three separate pockets to accommodate the substrate into the active site of each PTE. This enzyme generally shows a high catalytic activity towards phosphotriesters. These microbial enzymes are robust and easy to manipulate. Currently, PTEs are widely studied for the detection, detoxification, and enzyme therapies for OP compound poisoning incidents. The discovery and understanding of PTEs would pave ways for greener approaches in biotechnological applications and to solve environmental issues relating to OP contamination.
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Breger JC, Oh E, Susumu K, Klein WP, Walper SA, Ancona MG, Medintz IL. Nanoparticle Size Influences Localized Enzymatic Enhancement—A Case Study with Phosphotriesterase. Bioconjug Chem 2019; 30:2060-2074. [DOI: 10.1021/acs.bioconjchem.9b00362] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Joyce C. Breger
- Center for Bio/Molecular Science and Engineering, Code 6900, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States
| | - Eunkeu Oh
- Optical Sciences Division, Code 5600, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States
- KeyW Corporation, Hanover, Maryland 21076, United States
| | - Kimihiro Susumu
- Optical Sciences Division, Code 5600, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States
- KeyW Corporation, Hanover, Maryland 21076, United States
| | - William P. Klein
- Center for Bio/Molecular Science and Engineering, Code 6900, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States
- National Research Council, Washington, D.C. 20001, United States
| | - Scott A. Walper
- Center for Bio/Molecular Science and Engineering, Code 6900, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States
| | - Mario G. Ancona
- Electronics Science and Technology Division, Code 6800, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States
| | - Igor L. Medintz
- Center for Bio/Molecular Science and Engineering, Code 6900, U.S. Naval Research Laboratory, Washington, D.C. 20375, United States
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Fan F, Zheng Y, Zhang Y, Zheng H, Zhong J, Cao Z. A Comprehensive Understanding of Enzymatic Degradation of the G-Type Nerve Agent by Phosphotriesterase: Revised Role of Water Molecules and Rate-Limiting Product Release. ACS Catal 2019. [DOI: 10.1021/acscatal.9b01877] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Fangfang Fan
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 360015, People’s Republic of China
| | - Yongchao Zheng
- State Key Laboratory of NBC Protection for Civilian, Beijing 102205, People’s Republic of China
| | - Yuwei Zhang
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 360015, People’s Republic of China
| | - He Zheng
- State Key Laboratory of NBC Protection for Civilian, Beijing 102205, People’s Republic of China
| | - Jinyi Zhong
- State Key Laboratory of NBC Protection for Civilian, Beijing 102205, People’s Republic of China
| | - Zexing Cao
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 360015, People’s Republic of China
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36
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[Organophosphorus poisoning: Towards enzymatic treatments]. ANNALES PHARMACEUTIQUES FRANÇAISES 2019; 77:349-362. [PMID: 31253354 DOI: 10.1016/j.pharma.2019.06.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 06/05/2019] [Accepted: 06/05/2019] [Indexed: 11/22/2022]
Abstract
Organophosphorus compounds (OP) are toxic molecules developed as insecticides and chemical warfare nerve agents (CWNAs). Most OP are neurotoxic and act as nervous system disruptors by blocking cholinergic transmission. They are therefore responsible for many poisonings worldwide. OP toxicity may result either from acute or chronic exposure, and their poisoning effect were evaluated using several animal models. These latter were also used for evaluating the efficacy of antidotes. Strategies based on enzymes that can trap (stoichiometric bioscavengers) or degrade (catalytic bioscavengers) OP, were particularly studied since they allow effective decontamination, without toxicity or environmental impact. This review summarizes the results obtained in vivo with enzymes through three levels: prophylaxis, treatment and external decontamination. The efficiency of enzymatic treatments in different animal models is presented and the relevance of these models is also discussed for a better extrapolation to humans.
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37
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The evolution of phosphotriesterase for decontamination and detoxification of organophosphorus chemical warfare agents. Chem Biol Interact 2019; 308:80-88. [PMID: 31100274 DOI: 10.1016/j.cbi.2019.05.023] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 04/22/2019] [Accepted: 05/13/2019] [Indexed: 11/23/2022]
Abstract
The organophosphorus chemical warfare agents were initially synthesized in the 1930's and are some of the most toxic compounds ever discovered. The standard means of decontamination are either harsh chemical hydrolysis or high temperature incineration. Given the continued use of chemical warfare agents there are ongoing efforts to develop gentle environmentally friendly means of decontamination and medical counter measures to chemical warfare agent intoxication. Enzymatic decontamination offers the benefits of extreme specificity and mild conditions, allowing their use for both environmental and medical applications. The most promising enzyme for decontamination of the organophosphorus chemical warfare agents is the enzyme phosphotriesterase from Pseudomonas diminuta. However, the catalytic activity of the wild-type enzyme with the chemical warfare agents falls far below that seen with its best substrates, and its stereochemical preference is for the less toxic enantiomer of the chiral phosphorus center found in most chemical warfare agents. Rational design efforts have succeeded in the dramatic improvement of the stereochemical preference of PTE for the more toxic enantiomers. Directed evolution experiments, including site-saturation mutagenesis, targeted error-prone PCR, computational design, and quantitative library analysis, have systematically improved the catalytic activity against the chemical warfare nerve agents. These efforts have resulted in greater than 4-orders of magnitude improvement in catalytic activity and have led to the identification of variants that are highly effective at detoxifying both G-type and V-type nerve agents. The best of these variants have the ability to prevent intoxication when delivered as a post-exposure treatment for VX and as a pre-exposure treatment for G-agent intoxication with observed protective factors up to 60-fold. Combining the best variant, H257Y/L303T, with a PCB polymer coating has enabled the development of a long lasting circulating prophylactic treatment that is highly effective against sarin.
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Bigley AN, Desormeaux E, Xiang DF, Bae SY, Harvey SP, Raushel FM. Overcoming the Challenges of Enzyme Evolution To Adapt Phosphotriesterase for V-Agent Decontamination. Biochemistry 2019; 58:2039-2053. [DOI: 10.1021/acs.biochem.9b00097] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Andrew N. Bigley
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Emily Desormeaux
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Dao Feng Xiang
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Sue Y. Bae
- U.S. Army Edgewood Chemical Biological Center, 5183 Blackhawk Road, Aberdeen Proving Ground, Maryland 21010, United States
| | - Steven P. Harvey
- U.S. Army Edgewood Chemical Biological Center, 5183 Blackhawk Road, Aberdeen Proving Ground, Maryland 21010, United States
| | - Frank M. Raushel
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
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Bigley AN, Xiang DF, Narindoshvili T, Burgert CW, Hengge AC, Raushel FM. Transition State Analysis of the Reaction Catalyzed by the Phosphotriesterase from Sphingobium sp. TCM1. Biochemistry 2019; 58:1246-1259. [PMID: 30730705 DOI: 10.1021/acs.biochem.9b00041] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Organophosphorus flame retardants are stable toxic compounds used in nearly all durable plastic products and are considered major emerging pollutants. The phosphotriesterase from Sphingobium sp. TCM1 ( Sb-PTE) is one of the few enzymes known to be able to hydrolyze organophosphorus flame retardants such as triphenyl phosphate and tris(2-chloroethyl) phosphate. The effectiveness of Sb-PTE for the hydrolysis of these organophosphates appears to arise from its ability to hydrolyze unactivated alkyl and phenolic esters from the central phosphorus core. How Sb-PTE is able to catalyze the hydrolysis of the unactivated substituents is not known. To interrogate the catalytic hydrolysis mechanism of Sb-PTE, the pH dependence of the reaction and the effects of changing the solvent viscosity were determined. These experiments were complemented by measurement of the primary and secondary 18-oxygen isotope effects on substrate hydrolysis and a determination of the effects of changing the p Ka of the leaving group on the magnitude of the rate constants for hydrolysis. Collectively, the results indicated that a single group must be ionized for nucleophilic attack and that a separate general acid is not involved in protonation of the leaving group. The Brønsted analysis and the heavy atom kinetic isotope effects are consistent with an early associative transition state with subsequent proton transfers not being rate limiting. A novel binding mode of the substrate to the binuclear metal center and a catalytic mechanism are proposed to explain the unusual ability of Sb-PTE to hydrolyze unactivated esters from a wide range of organophosphate substrates.
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Affiliation(s)
- Andrew N Bigley
- Department of Chemistry , Texas A&M University , College Station , Texas 77843 , United States
| | - Dao Feng Xiang
- Department of Chemistry , Texas A&M University , College Station , Texas 77843 , United States
| | - Tamari Narindoshvili
- Department of Chemistry , Texas A&M University , College Station , Texas 77843 , United States
| | - Charlie W Burgert
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
| | - Alvan C Hengge
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
| | - Frank M Raushel
- Department of Chemistry , Texas A&M University , College Station , Texas 77843 , United States
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Zhang P, Liu EJ, Tsao C, Kasten SA, Boeri MV, Dao TL, DeBus SJ, Cadieux CL, Baker CA, Otto TC, Cerasoli DM, Chen Y, Jain P, Sun F, Li W, Hung HC, Yuan Z, Ma J, Bigley AN, Raushel FM, Jiang S. Nanoscavenger provides long-term prophylactic protection against nerve agents in rodents. Sci Transl Med 2019; 11:11/473/eaau7091. [DOI: 10.1126/scitranslmed.aau7091] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2018] [Accepted: 12/06/2018] [Indexed: 12/24/2022]
Abstract
Nerve agents are a class of organophosphorus compounds (OPs) that blocks communication between nerves and organs. Because of their acute neurotoxicity, it is extremely difficult to rescue the victims after exposure. Numerous efforts have been devoted to search for an effective prophylactic nerve agent bioscavenger to prevent the deleterious effects of these compounds. However, low scavenging efficiency, unfavorable pharmacokinetics, and immunological problems have hampered the development of effective drugs. Here, we report the development and testing of a nanoparticle-based nerve agent bioscavenger (nanoscavenger) that showed long-term protection against OP intoxication in rodents. The nanoscavenger, which catalytically breaks down toxic OP compounds, showed a good pharmacokinetic profile and negligible immune response in a rat model of OP intoxication. In vivo administration of the nanoscavenger before or after OP exposure in animal models demonstrated protective and therapeutic efficacy. In a guinea pig model, a single prophylactic administration of the nanoscavenger effectively prevented lethality after multiple sarin exposures over a 1-week period. Our results suggest that the prophylactic administration of the nanoscavenger might be effective in preventing the toxic effects of OP exposure in humans.
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41
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Wang R, Pan J, Qin M, Guo T. Molecularly imprinted nanocapsule mimicking phosphotriesterase for the catalytic hydrolysis of organophosphorus pesticides. Eur Polym J 2019. [DOI: 10.1016/j.eurpolymj.2018.10.045] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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42
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Porzio E, Bettazzi F, Mandrich L, Del Giudice I, Restaino OF, Laschi S, Febbraio F, De Luca V, Borzacchiello MG, Carusone TM, Worek F, Pisanti A, Porcaro P, Schiraldi C, De Rosa M, Palchetti I, Manco G. Innovative Biocatalysts as Tools to Detect and Inactivate Nerve Agents. Sci Rep 2018; 8:13773. [PMID: 30214052 PMCID: PMC6137069 DOI: 10.1038/s41598-018-31751-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2018] [Accepted: 07/25/2018] [Indexed: 11/13/2022] Open
Abstract
Pesticides and warfare nerve agents are frequently organophosphates (OPs) or related compounds. Their acute toxicity highlighted more than ever the need to explore applicable strategies for the sensing, decontamination and/or detoxification of these compounds. Herein, we report the use of two different thermostable enzyme families capable to detect and inactivate OPs. In particular, mutants of carboxylesterase-2 from Alicyclobacillus acidocaldarius and of phosphotriesterase-like lactonases from Sulfolobus solfataricus and Sulfolobus acidocaldarius, have been selected and assembled in an optimized format for the development of an electrochemical biosensor and a decontamination formulation, respectively. The features of the developed tools have been tested in an ad-hoc fabricated chamber, to mimic an alarming situation of exposure to a nerve agent. Choosing ethyl-paraoxon as nerve agent simulant, a limit of detection (LOD) of 0.4 nM, after 5 s of exposure time was obtained. Furthermore, an optimized enzymatic formulation was used for a fast and efficient environmental detoxification (>99%) of the nebulized nerve agent simulants in the air and on surfaces. Crucial, large-scale experiments have been possible thanks to production of grams amounts of pure (>90%) enzymes.
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Affiliation(s)
- Elena Porzio
- Institute of Protein Biochemistry, National Research Council of Italy, Naples, Italy
| | - Francesca Bettazzi
- Department of Chemistry, University of Florence, Sesto Fiorentino (FI), Italy
| | - Luigi Mandrich
- Institute of Protein Biochemistry, National Research Council of Italy, Naples, Italy
| | | | | | | | - Ferdinando Febbraio
- Institute of Protein Biochemistry, National Research Council of Italy, Naples, Italy
| | - Valentina De Luca
- Institute of Protein Biochemistry, National Research Council of Italy, Naples, Italy
| | | | - Teresa M Carusone
- Institute of Protein Biochemistry, National Research Council of Italy, Naples, Italy
| | - Franz Worek
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany
| | | | | | | | - Mario De Rosa
- University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Ilaria Palchetti
- Department of Chemistry, University of Florence, Sesto Fiorentino (FI), Italy
| | - Giuseppe Manco
- Institute of Protein Biochemistry, National Research Council of Italy, Naples, Italy.
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43
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Catalytic bioscavengers as countermeasures against organophosphate nerve agents. Chem Biol Interact 2018; 292:50-64. [DOI: 10.1016/j.cbi.2018.07.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2018] [Revised: 07/04/2018] [Accepted: 07/06/2018] [Indexed: 12/30/2022]
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44
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Investigation of interaction modes involved in alkaline phosphatase and organophosphorus pesticides via molecular simulations. Food Chem 2018; 254:80-86. [DOI: 10.1016/j.foodchem.2018.01.187] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Revised: 01/06/2018] [Accepted: 01/31/2018] [Indexed: 11/24/2022]
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45
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Olsen AJ, Halvorsen LA, Yang CY, Barak Ventura R, Yin L, Renfrew PD, Bonneau R, Montclare JK. Impact of phenylalanines outside the dimer interface on phosphotriesterase stability and function. MOLECULAR BIOSYSTEMS 2018; 13:2092-2106. [PMID: 28817149 DOI: 10.1039/c7mb00196g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We explore the significance of phenylalanine outside of the phosphotriesterase (PTE) dimer interface through mutagenesis studies and computational modeling. Previous studies have demonstrated that the residue-specific incorporation of para-fluorophenylalanine (pFF) into PTE improves stability, suggesting the importance of phenylalanines in stabilization of the dimer. However, this comes at a cost of decreased solubility due to pFF incorporation into other parts of the protein. Motivated by this, eight single solvent-exposed phenylalanine mutants are evaluated viarosetta and good correspondence between experiments and these predictions is observed. Three residues, F304, F327, and F335, appear to be important for PTE activity and stability, even though they do not reside in the dimer interface region or active site. While the remaining mutants do not significantly affect structure or activity, one variant, F306L, reveals improved activity at ambient and elevated temperatures. These studies provide further insight into role of these residues on PTE function and stability.
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Affiliation(s)
- Andrew J Olsen
- Department of Chemical and Biomolecular Engineering, New York University, Tandon School of Engineering, New York 11201, USA
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46
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Microbiota-Mediated Modulation of Organophosphate Insecticide Toxicity by Species-Dependent Interactions with Lactobacilli in a Drosophila melanogaster Insect Model. Appl Environ Microbiol 2018; 84:AEM.02820-17. [PMID: 29475860 DOI: 10.1128/aem.02820-17] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 02/14/2018] [Indexed: 01/06/2023] Open
Abstract
Despite the benefits to the global food supply and agricultural economies, pesticides are believed to pose a threat to the health of both humans and wildlife. Chlorpyrifos (CP), a commonly used organophosphate insecticide, has poor target specificity and causes acute neurotoxicity in a wide range of species via the suppression of acetylcholinesterase. This effect is exacerbated 10- to 100-fold by chlorpyrifos oxon (CPO), a principal metabolite of CP. Since many animal-associated symbiont microorganisms are known to hydrolyze CP into CPO, we used a Drosophila melanogaster insect model to investigate the hypothesis that indigenous and probiotic bacteria could affect CP metabolism and toxicity. Antibiotic-treated and germfree D. melanogaster insects lived significantly longer than their conventionally reared counterparts when exposed to 10 μM CP. Drosophila melanogaster gut-derived Lactobacillus plantarum, but not Acetobacterindonesiensis, was shown to metabolize CP. Liquid chromatography tandem-mass spectrometry confirmed that the L. plantarum isolate preferentially metabolized CP into CPO when grown in CP-spiked culture medium. Further experiments showed that monoassociating germfree D. melanogaster with the L. plantarum isolate could reestablish a conventional-like sensitivity to CP. Interestingly, supplementation with the human probiotic Lactobacillus rhamnosus GG (a strain that binds but does not metabolize CP) significantly increased the survival of the CP-exposed germfree D. melanogaster This suggests strain-specific differences in CP metabolism may exist among lactobacilli and emphasizes the need for further investigation. In summary, these results suggest that (i) CPO formation by the gut microbiota can have biologically relevant consequences for the host, and (ii) probiotic lactobacilli may be beneficial in reducing in vivo CP toxicity.IMPORTANCE An understudied area of research is how the microbiota (microorganisms living in/on an animal) affects the metabolism and toxic outcomes of environmental pollutants such as pesticides. This study focused specifically on how the microbial biotransformation of chlorpyrifos (CP; a common organophosphate insecticide) affected host exposure and toxicity parameters in a Drosophila melanogaster insect model. Our results demonstrate that the biotransformation of CP by the gut microbiota had biologically relevant and toxic consequences on host health and that certain probiotic lactobacilli may be beneficial in reducing CP toxicity. Since inadvertent pesticide exposure is suspected to negatively impact the health of off-target species, these findings may provide useful information for wildlife conservation and environmental sustainability planning. Furthermore, the results highlight the need to consider microbiota composition differences between beneficial and pest insects in future insecticide designs. More broadly, this study supports the use of beneficial microorganisms to modulate the microbiota-mediated biotransformation of xenobiotics.
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47
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Alejo-González K, Hanson-Viana E, Vazquez-Duhalt R. Enzymatic detoxification of organophosphorus pesticides and related toxicants. JOURNAL OF PESTICIDE SCIENCE 2018; 43:1-9. [PMID: 30363124 PMCID: PMC6140661 DOI: 10.1584/jpestics.d17-078] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 01/08/2018] [Indexed: 05/20/2023]
Abstract
Millions of cases of pesticide intoxication occur yearly and represent a public health problem. In addition, pesticide poisoning is the preferred suicidal method in rural areas. The use of enzymes for the treatment of intoxication due to organophosphorus pesticides was proposed decades ago. Several enzymes are able to transform organophosphorus compounds such as pesticides and nerve agents. Some specific enzymatic treatments have been proposed, including direct enzyme injection, liposome and erythrocytes carriers, PEGylated preparations and extracorporeal enzymatic treatments. Nevertheless, no enzymatic treatments are currently available. In this work, the use of enzymes for treating of organophosphorus pesticide intoxication is critically reviewed and the remaining challenges are discussed.
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Affiliation(s)
- Karla Alejo-González
- Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, Km 107 carretera Tijuana-Ensenada, Ensenada, Baja California 22760 México
| | - Erik Hanson-Viana
- Facultad de Medicina, Universidad Autónoma de Baja California, Mexicali, Mexico
| | - Rafael Vazquez-Duhalt
- Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, Km 107 carretera Tijuana-Ensenada, Ensenada, Baja California 22760 México
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48
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Rhoads MK, Hauk P, Gupta V, Bookstaver ML, Stephens K, Payne GF, Bentley WE. Modification and Assembly of a Versatile Lactonase for Bacterial Quorum Quenching. Molecules 2018; 23:E341. [PMID: 29415497 PMCID: PMC6016966 DOI: 10.3390/molecules23020341] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 01/23/2018] [Accepted: 01/23/2018] [Indexed: 01/05/2023] Open
Abstract
This work sets out to provide a self-assembled biopolymer capsule activated with a multi-functional enzyme for localized delivery. This enzyme, SsoPox, which is a lactonase and phosphotriesterase, provides a means of interrupting bacterial communication pathways that have been shown to mediate pathogenicity. Here we demonstrate the capability to express, purify and attach SsoPox to the natural biopolymer chitosan, preserving its activity to "neutralize" long-chain autoinducer-1 (AI-1) communication molecules. Attachment is shown via non-specific binding and by engineering tyrosine and glutamine affinity 'tags' at the C-terminus for covalent linkage. Subsequent degradation of AI-1, in this case N-(3-oxododecanoyl)-l-homoserine lactone (OdDHL), serves to "quench" bacterial quorum sensing (QS), silencing intraspecies communication. By attaching enzymes to pH-responsive chitosan that, in turn, can be assembled into various forms, we demonstrate device-based flexibility for enzyme delivery. Specifically, we have assembled quorum-quenching capsules consisting of an alginate inner core and an enzyme "decorated" chitosan shell that are shown to preclude bacterial QS crosstalk, minimizing QS mediated behaviors.
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Affiliation(s)
- Melissa K Rhoads
- Institute for Bioscience and Biotechnology Research (IBBR), University of Maryland, College Park, MD 20742, USA.
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA.
| | - Pricila Hauk
- Institute for Bioscience and Biotechnology Research (IBBR), University of Maryland, College Park, MD 20742, USA.
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA.
| | - Valerie Gupta
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA.
| | - Michelle L Bookstaver
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA.
| | - Kristina Stephens
- Institute for Bioscience and Biotechnology Research (IBBR), University of Maryland, College Park, MD 20742, USA.
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA.
| | - Gregory F Payne
- Institute for Bioscience and Biotechnology Research (IBBR), University of Maryland, College Park, MD 20742, USA.
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA.
| | - William E Bentley
- Institute for Bioscience and Biotechnology Research (IBBR), University of Maryland, College Park, MD 20742, USA.
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA.
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49
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Poole JL, Donahue S, Wilson D, Li YM, Zhang Q, Gu Y, Ferebee R, Lu Z, Dorin RM, Hancock LF, Takiff L, Hakem IF, Bockstaller MR, Wiesner U, Walker J. Biocatalytic Stimuli‐Responsive Asymmetric Triblock Terpolymer Membranes for Localized Permeability Gating. Macromol Rapid Commun 2017; 38. [DOI: 10.1002/marc.201700364] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 07/10/2017] [Indexed: 11/09/2022]
Affiliation(s)
| | - Scott Donahue
- FLIR Systems, Inc. 2240 William Pitt Way Pittsburgh PA 15238 USA
| | - David Wilson
- FLIR Systems, Inc. 2240 William Pitt Way Pittsburgh PA 15238 USA
| | - Yuk Mun Li
- Robert Frederick Smith School of Chemical and Biomolecular Engineering Cornell University Ithaca NY 14853 USA
| | - Qi Zhang
- Department of Materials Science and Engineering Cornell University Ithaca NY 14853 USA
| | - Yibei Gu
- Department of Materials Science and Engineering Cornell University Ithaca NY 14853 USA
| | - Rachel Ferebee
- Department of Materials Science and Engineering Carnegie Mellon University 5000 Forbes Ave. Pittsburgh PA 15213 USA
| | - Zhao Lu
- Department of Materials Science and Engineering Carnegie Mellon University 5000 Forbes Ave. Pittsburgh PA 15213 USA
| | - Rachel Mika Dorin
- Terapore Technologies, Inc. 407 Cabot Rd. South San Francisco CA 94080 USA
| | | | - Larry Takiff
- Akita Innovations LLC 267 Boston Rd., Suite 11, Billerica MA 01862 USA
| | - Ilhem F. Hakem
- Department of Materials Science and Engineering Carnegie Mellon University 5000 Forbes Ave. Pittsburgh PA 15213 USA
| | - Michael R. Bockstaller
- Department of Materials Science and Engineering Carnegie Mellon University 5000 Forbes Ave. Pittsburgh PA 15213 USA
| | - Ulrich Wiesner
- Department of Materials Science and Engineering Cornell University Ithaca NY 14853 USA
| | - Jeremy Walker
- FLIR Systems, Inc. 2240 William Pitt Way Pittsburgh PA 15238 USA
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50
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de Castro AA, Assis LC, Silva DR, Corrêa S, Assis TM, Gajo GC, Soares FV, Ramalho TC. Computational enzymology for degradation of chemical warfare agents: promising technologies for remediation processes. AIMS Microbiol 2017; 3:108-135. [PMID: 31294152 PMCID: PMC6604975 DOI: 10.3934/microbiol.2017.1.108] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 02/14/2017] [Indexed: 11/18/2022] Open
Abstract
Chemical weapons are a major worldwide problem, since they are inexpensive, easy to produce on a large scale and difficult to detect and control. Among the chemical warfare agents, we can highlight the organophosphorus compounds (OP), which contain the phosphorus element and that have a large number of applications. They affect the central nervous system and can lead to death, so there are a lot of works in order to design new effective antidotes for the intoxication caused by them. The standard treatment includes the use of an anticholinergic combined to a central nervous system depressor and an oxime. Oximes are compounds that reactivate Acetylcholinesterase (AChE), a regulatory enzyme responsible for the transmission of nerve impulses, which is one of the molecular targets most vulnerable to neurotoxic agents. Increasingly, enzymatic treatment becomes a promising alternative; therefore, other enzymes have been studied for the OP degradation function, such as phosphotriesterase (PTE) from bacteria, human serum paraoxonase 1 (HssPON1) and diisopropyl fluorophosphatase (DFPase) that showed significant performances in OP detoxification. The understanding of mechanisms by which enzymes act is of extreme importance for the projection of antidotes for warfare agents, and computational chemistry comes to aid and reduce the time and costs of the process. Molecular Docking, Molecular Dynamics and QM/MM (quantum-mechanics/molecular-mechanics) are techniques used to investigate the molecular interactions between ligands and proteins.
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Affiliation(s)
| | - Letícia C. Assis
- Department of Chemistry, Federal University of Lavras, 37200-000, Lavras, Brazil
| | - Daniela R. Silva
- Department of Chemistry, Federal University of Lavras, 37200-000, Lavras, Brazil
| | - Silviana Corrêa
- Department of Chemistry, Federal University of Lavras, 37200-000, Lavras, Brazil
| | - Tamiris M. Assis
- Department of Chemistry, Federal University of Lavras, 37200-000, Lavras, Brazil
| | - Giovanna C. Gajo
- Department of Chemistry, Federal University of Lavras, 37200-000, Lavras, Brazil
| | - Flávia V. Soares
- Department of Chemistry, Federal University of Lavras, 37200-000, Lavras, Brazil
| | - Teodorico C. Ramalho
- Department of Chemistry, Federal University of Lavras, 37200-000, Lavras, Brazil
- Center for Basic and Applied Research, Faculty of Informatics and Management, University of Hradec Kralove, Rokitanskeho 62, 50003, Czech Republic
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