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Kohoutova Z, Prchalova E, Knittelova K, Musilek K, Malinak D. Reactivators of butyrylcholinesterase inhibited by organophosphorus compounds. Bioorg Chem 2024; 150:107526. [PMID: 38878749 DOI: 10.1016/j.bioorg.2024.107526] [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: 02/27/2024] [Revised: 05/16/2024] [Accepted: 06/02/2024] [Indexed: 07/21/2024]
Abstract
In this review, the current progress in the research and development of butyrylcholinesterase (BChE) reactivators is summarised and the advantages or disadvantages of these reactivators are critically discussed. Organophosphorus compounds such as nerve agents (sarin, tabun, VX) or pesticides (chlorpyrifos, diazinon) cause irreversible inhibition of acetylcholinesterase (AChE) and BChE in the human body. While AChE inhibition can be life threatening due to cholinergic overstimulation and crisis, selective BChE inhibition has presumably no adverse effects. Because BChE is mostly found in plasma, its activity is important for the scavenging of organophosphates before they can reach AChE in the central nervous system. Therefore, this enzyme in combination with its reactivator can be used as a pseudo-catalytic scavenger of organophosphates. Three structural types of BChE reactivators were found, i.e. bisquaternary salts, monoquaternary salts and uncharged compounds. Although the reviewed reactivators have certain limitations, the promising candidates for BChE reactivation were found in each structural group.
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Affiliation(s)
- Zuzana Kohoutova
- University of Hradec Kralove, Faculty of Science, Department of Chemistry, Rokitanskeho 62, 500 03 Hradec Kralove, Czech Republic
| | - Eliska Prchalova
- University of Hradec Kralove, Faculty of Science, Department of Chemistry, Rokitanskeho 62, 500 03 Hradec Kralove, Czech Republic
| | - Karolina Knittelova
- University of Hradec Kralove, Faculty of Science, Department of Chemistry, Rokitanskeho 62, 500 03 Hradec Kralove, Czech Republic
| | - Kamil Musilek
- University of Hradec Kralove, Faculty of Science, Department of Chemistry, Rokitanskeho 62, 500 03 Hradec Kralove, Czech Republic; University Hospital in Hradec Kralove, Biomedical Research Centre, Sokolska 581, 500 05 Hradec Kralove, Czech Republic
| | - David Malinak
- University of Hradec Kralove, Faculty of Science, Department of Chemistry, Rokitanskeho 62, 500 03 Hradec Kralove, Czech Republic; University Hospital in Hradec Kralove, Biomedical Research Centre, Sokolska 581, 500 05 Hradec Kralove, Czech Republic.
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Jaiswal S, Singh B, Dhingra I, Joshi A, Kodgire P. Bioremediation and bioscavenging for elimination of organophosphorus threats: An approach using enzymatic advancements. ENVIRONMENTAL RESEARCH 2024; 252:118888. [PMID: 38599448 DOI: 10.1016/j.envres.2024.118888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 02/06/2024] [Accepted: 04/05/2024] [Indexed: 04/12/2024]
Abstract
Organophosphorus compounds (OP) are highly toxic pesticides and nerve agents widely used in agriculture and chemical warfare. The extensive use of these chemicals has severe environmental implications, such as contamination of soil, water bodies, and food chains, thus endangering ecosystems and biodiversity. Plants absorb pesticide residues, which then enter the food chain and accumulate in the body fat of both humans and animals. Numerous human cases of OP poisoning have been linked to both acute and long-term exposure to these toxic OP compounds. These compounds inhibit the action of the acetylcholinesterase enzyme (AChE) by phosphorylation, which prevents the breakdown of acetylcholine (ACh) neurotransmitter into choline and acetate. Thus, it becomes vital to cleanse the environment from these chemicals utilizing various physical, chemical, and biological methods. Biological methods encompassing bioremediation using immobilized microbes and enzymes have emerged as environment-friendly and cost-effective approaches for pesticide removal. Cell/enzyme immobilized systems offer higher stability, reusability, and ease of product recovery, making them ideal tools for OP bioremediation. Interestingly, enzymatic bioscavengers (stoichiometric, pseudo-catalytic, and catalytic) play a vital role in detoxifying pesticides from the human body. Catalytic bioscavenging enzymes such as Organophosphate Hydrolase, Organophosphorus acid anhydrolase, and Paraoxonase 1 show high degradation efficiency within the animal body as well as in the environment. Moreover, these enzymes can also be employed to decontaminate pesticides from food, ensuring food safety and thus minimizing human exposure. This review aims to provide insights to potential collaborators in research organizations, government bodies, and industries to bring advancements in the field of bioremediation and bioscavenging technologies for the mitigation of OP-induced health hazards.
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Affiliation(s)
- Surbhi Jaiswal
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology, Indore, Simrol, Khandwa Road, Indore, 453552, India
| | - Brijeshwar Singh
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology, Indore, Simrol, Khandwa Road, Indore, 453552, India
| | - Isha Dhingra
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology, Indore, Simrol, Khandwa Road, Indore, 453552, India
| | - Abhijeet Joshi
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology, Indore, Simrol, Khandwa Road, Indore, 453552, India.
| | - Prashant Kodgire
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology, Indore, Simrol, Khandwa Road, Indore, 453552, India.
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Li H, Lu C, Liu Z, Xiang F, Liu B, Wang H, Chang J, Pan L, Chen Y, Chen J. Advancements in bioscavenger mediated detoxification of organophosphorus poisoning. Toxicol Res (Camb) 2024; 13:tfae089. [PMID: 38863796 PMCID: PMC11163184 DOI: 10.1093/toxres/tfae089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Accepted: 06/04/2024] [Indexed: 06/13/2024] Open
Abstract
Background Organophosphorus compounds, widely used in agriculture and industry, pose a serious threat to human health due to their acute neurotoxicity. Although traditional interventions for organophosphate poisoning are effective, they often come with significant side effects. Objective This paper aims to evaluate the potential of enzymes within biological organisms as organophosphorus bioclearing agents. It analyses the technical challenges in current enzyme research, such as substrate specificity, stereoselectivity, and immunogenicity, while exploring recent advancements in the field. Methods A comprehensive review of literature related to detoxifying enzymes or proteins was conducted. Existing studies on organophosphorus bioclearing agents were summarised, elucidating the biological detoxification mechanisms, with a particular focus on advancements in protein engineering and novel delivery methods. Results Current bioclearing agents can be categorised into stoichiometric and catalytic bioclearing agents, both of which have shown some success in preventing organophosphate poisoning. Technological advancements have significantly improved various properties of bioclearing agents, yet challenges remain, particularly in substrate specificity, stereoselectivity, and immunogenicity. Future research will focus on expanding the substrate spectrum, enhancing catalytic efficiency, prolonging in vivo half-life, and developing convenient administration methods. Conclusion With the progression of clinical trials, bioclearing agents are expected to become widely used as a new generation of therapeutic organophosphate detoxifiers.
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Affiliation(s)
- Hexi Li
- Institute of NBC Defence, PLA, ARMY, 1 North Street, Yangfang Town, Changping District, Beijing 102205, China
- Unit No. 31666 of PLA, 1 New City Courtyard, Jinyang Town, Liangzhou District, Wuwei, Gansu 733000, China
| | - Cong Lu
- Institute of NBC Defence, PLA, ARMY, 1 North Street, Yangfang Town, Changping District, Beijing 102205, China
- Unit No. 94347 of PLA, 24 Wenfu Road, Shenhe District, Shenyang, Liaoning 110000, China
| | - Zhenmin Liu
- Institute of NBC Defence, PLA, ARMY, 1 North Street, Yangfang Town, Changping District, Beijing 102205, China
| | - Fengshun Xiang
- Institute of NBC Defence, PLA, ARMY, 1 North Street, Yangfang Town, Changping District, Beijing 102205, China
| | - Bo Liu
- Institute of NBC Defence, PLA, ARMY, 1 North Street, Yangfang Town, Changping District, Beijing 102205, China
| | - Hongjuan Wang
- Institute of NBC Defence, PLA, ARMY, 1 North Street, Yangfang Town, Changping District, Beijing 102205, China
| | - Jie Chang
- Institute of NBC Defence, PLA, ARMY, 1 North Street, Yangfang Town, Changping District, Beijing 102205, China
| | - Li Pan
- State Key Laboratory of NBC Protection for Civilians, 30 South Central Street, Yangfang Town, Changping District, Beijing 102205, P. R. China
| | - Youwei Chen
- Institute of NBC Defence, PLA, ARMY, 1 North Street, Yangfang Town, Changping District, Beijing 102205, China
| | - Jingfei Chen
- Institute of NBC Defence, PLA, ARMY, 1 North Street, Yangfang Town, Changping District, Beijing 102205, China
- Unit No. 32169 of PLA, 100 Shuangyong East Road, Nyingchi, Tibet 860000, China
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Pashirova T, Shaihutdinova Z, Tatarinov D, Mansurova M, Kazakova R, Bogdanov A, Chabrière E, Jacquet P, Daudé D, Akhunzianov AA, Miftakhova RR, Masson P. Tuning the Envelope Structure of Enzyme Nanoreactors for In Vivo Detoxification of Organophosphates. Int J Mol Sci 2023; 24:15756. [PMID: 37958742 PMCID: PMC10649860 DOI: 10.3390/ijms242115756] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Revised: 10/26/2023] [Accepted: 10/26/2023] [Indexed: 11/15/2023] Open
Abstract
Encapsulated phosphotriesterase nanoreactors show their efficacy in the prophylaxis and post-exposure treatment of poisoning by paraoxon. A new enzyme nanoreactor (E-nRs) containing an evolved multiple mutant (L72C/Y97F/Y99F/W263V/I280T) of Saccharolobus solfataricus phosphotriesterase (PTE) for in vivo detoxification of organophosphorous compounds (OP) was made. A comparison of nanoreactors made of three- and di-block copolymers was carried out. Two types of morphology nanoreactors made of di-block copolymers were prepared and characterized as spherical micelles and polymersomes with sizes of 40 nm and 100 nm, respectively. The polymer concentrations were varied from 0.1 to 0.5% (w/w) and enzyme concentrations were varied from 2.5 to 12.5 μM. In vivo experiments using E-nRs of diameter 106 nm, polydispersity 0.17, zeta-potential -8.3 mV, and loading capacity 15% showed that the detoxification efficacy against paraoxon was improved: the LD50 shift was 23.7xLD50 for prophylaxis and 8xLD50 for post-exposure treatment without behavioral alteration or functional physiological changes up to one month after injection. The pharmacokinetic profiles of i.v.-injected E-nRs made of three- and di-block copolymers were similar to the profiles of the injected free enzyme, suggesting partial enzyme encapsulation. Indeed, ELISA and Western blot analyses showed that animals developed an immune response against the enzyme. However, animals that received several injections did not develop iatrogenic symptoms.
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Affiliation(s)
- Tatiana Pashirova
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, Arbuzov Str., 8, 420088 Kazan, Russia; (Z.S.); (D.T.); (A.B.)
| | - Zukhra Shaihutdinova
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, Arbuzov Str., 8, 420088 Kazan, Russia; (Z.S.); (D.T.); (A.B.)
- Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia; (M.M.); (R.K.); (A.A.A.); (R.R.M.)
| | - Dmitry Tatarinov
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, Arbuzov Str., 8, 420088 Kazan, Russia; (Z.S.); (D.T.); (A.B.)
| | - Milana Mansurova
- Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia; (M.M.); (R.K.); (A.A.A.); (R.R.M.)
| | - Renata Kazakova
- Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia; (M.M.); (R.K.); (A.A.A.); (R.R.M.)
| | - Andrei Bogdanov
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, Arbuzov Str., 8, 420088 Kazan, Russia; (Z.S.); (D.T.); (A.B.)
| | - Eric Chabrière
- Gene&GreenTK, 19–21 Boulevard Jean Moulin, 13005 Marseille, France; (E.C.); (P.J.); (D.D.)
- IRD, APHM, MEPHI, IHU-Méditerranée Infection, Aix Marseille Université, 19–21 Boulevard Jean Moulin, 13005 Marseille, France
| | - Pauline Jacquet
- Gene&GreenTK, 19–21 Boulevard Jean Moulin, 13005 Marseille, France; (E.C.); (P.J.); (D.D.)
| | - David Daudé
- Gene&GreenTK, 19–21 Boulevard Jean Moulin, 13005 Marseille, France; (E.C.); (P.J.); (D.D.)
| | - Almaz A. Akhunzianov
- Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia; (M.M.); (R.K.); (A.A.A.); (R.R.M.)
| | - Regina R. Miftakhova
- Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia; (M.M.); (R.K.); (A.A.A.); (R.R.M.)
| | - Patrick Masson
- Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia; (M.M.); (R.K.); (A.A.A.); (R.R.M.)
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Pashirova TN, Shaihutdinova ZM, Mironov VF, Masson P. Biomedical Nanosystems for In Vivo Detoxification: From Passive Delivery Systems to Functional Nanodevices and Nanorobots. Acta Naturae 2023; 15:4-12. [PMID: 37153510 PMCID: PMC10154777 DOI: 10.32607/actanaturae.15681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 03/21/2023] [Indexed: 05/09/2023] Open
Abstract
The problem of low efficiency of nanotherapeutic drugs challenges the creation of new alternative biomedical nanosystems known as robotic nanodevices. In addition to encapsulating properties, nanodevices can perform different biomedical functions, such as precision surgery, in vivo detection and imaging, biosensing, targeted delivery, and, more recently, detoxification of endogenous and xenobiotic compounds. Nanodevices for detoxification are aimed at removing toxic molecules from biological tissues, using a chemical- and/or enzyme-containing nanocarrier for the toxicant to diffuse inside the nanobody. This strategy is opposite to drug delivery systems that focus on encapsulating drugs and releasing them under the influence of external factors. The review describes various kinds of nanodevices intended for detoxification that differ by the type of poisoning treatment they provide, as well as the type of materials and toxicants. The final part of the review is devoted to enzyme nanosystems, an emerging area of research that provides fast and effective neutralization of toxins in vivo.
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Affiliation(s)
- T. N. Pashirova
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center of RAS, Kazan, 420088 Russian Federation
| | - Z. M. Shaihutdinova
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center of RAS, Kazan, 420088 Russian Federation
- Kazan (Volga Region) Federal University, Kazan, 420008 Russian Federation
| | - V. F. Mironov
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center of RAS, Kazan, 420088 Russian Federation
| | - P. Masson
- Kazan (Volga Region) Federal University, Kazan, 420008 Russian Federation
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Lushchekina SV, Nemukhin AV, Polyakov IV, Masson P, Varfolomeev SD, Grigorenko BL. Spontaneous Reactivation of OPC-Inhibited BChE Mutants: Modeling of Mechanisms. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY B 2022. [DOI: 10.1134/s1990793122010237] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Paidi MK, Satapute P, Haider MS, Udikeri SS, Ramachandra YL, Vo DVN, Govarthanan M, Jogaiah S. Mitigation of organophosphorus insecticides from environment: Residual detoxification by bioweapon catalytic scavengers. ENVIRONMENTAL RESEARCH 2021; 200:111368. [PMID: 34081974 DOI: 10.1016/j.envres.2021.111368] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 05/09/2021] [Accepted: 05/16/2021] [Indexed: 06/12/2023]
Abstract
Organophosphorus insecticides (OPIs) have low persistence and are easily biodegradable in nature. The United States and India are the major countries producing OPIs of about 25% and 17% of the world, respectively. OPIs commonly used for agricultural practices occupy a major share in the global market, which leads to the increasing contamination of OPIs residues in various food chains. To overcome this issue, an enzymatic degradation method has been approved by several environmental toxic, and controlling agencies, including United States Environmental Protection Agency (USEPA). Different catalytic enzymes have been isolated and identified from various microbial sources to neutralize the toxic pesticides and/or insecticides. In this review, we have gathered information on OPIs biotransformation and their residual toxicity in the environment. Particularly, it focuses on OPIs degrading enzymes such as chlorpyrifos hydrolase, diisopropylfluorophosphatase, organophosphate acid anhydrolase, organophosphate hydrolases, and phosphotriesterases like lactonasesspecific activity either P-O link group type or P-S link group of pesticides. To summarize, the catalytic degradation of organophosphorus insecticides is not only profitable but also environmentally friendly. Hence, the enzymatic catalyst is an ultimate and super bio-weapon to mitigate or decontaminate various OPIs residues in both terrestrial and aqueous environments.
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Affiliation(s)
- Murali Krishna Paidi
- AcSIR, CSIR-Central Salt and Marine Chemicals Research Institute (CSIR-CSMCRI), Gijubhai Badheka Marg, Bhavnagar, Gujarat, 364002, India
| | - Praveen Satapute
- Laboratory of Plant Healthcare and Diagnostics, P.G. Department of Biotechnology and Microbiology, Karnatak University, Dharwad, Karnataka, 580003, India
| | - Muhammad Salman Haider
- Key Laboratory of Genetics and Fruit Development, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Shashikant Shiddappa Udikeri
- Agricultural Research Station, Dharwad Farm, University of Agricultural Sciences, Dharwad, 580005, Karnataka, India
| | | | - Dai-Viet N Vo
- Center of Excellence for Green Energy and Environmental Nanomaterials (CE@GrEEN), Nguyen Tat Thanh University, Ho Chi Minh City, Viet Nam
| | - Muthusamy Govarthanan
- Department of Environmental Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu, 41566, South Korea.
| | - Sudisha Jogaiah
- Laboratory of Plant Healthcare and Diagnostics, P.G. Department of Biotechnology and Microbiology, Karnatak University, Dharwad, Karnataka, 580003, India.
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Pashirova TN, Bogdanov A, Masson P. Therapeutic nanoreactors for detoxification of xenobiotics: Concepts, challenges and biotechnological trends with special emphasis to organophosphate bioscavenging. Chem Biol Interact 2021; 346:109577. [PMID: 34274336 DOI: 10.1016/j.cbi.2021.109577] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 06/19/2021] [Accepted: 07/12/2021] [Indexed: 12/20/2022]
Abstract
The introduction of enzyme nanoreactors in medicine is relatively new. However, this technology has already been experimentally successful in cancer treatments, struggle against toxicity of reactive oxygen species in inflammatory processes, detoxification of drugs and xenobiotics, and correction of metabolic and genetic defects by using encapsulated enzymes, acting in single or cascade reactions. Biomolecules, e.g. enzymes, antibodies, reactive proteins capable of inactivating toxicants in the body are called bioscavengers. In this review, we focus on enzyme-containing nanoreactors for in vivo detoxification of organophosphorous compounds (OP) to be used for prophylaxis and post-exposure treatment of OP poisoning. A particular attention is devoted to bioscavenger-containing injectable nanoreactors operating in the bloodstream. The nanoreactor concept implements single or multiple enzymes and cofactors co-encapsulated in polymeric semi-permeable nanocontainers. Thus, the detoxification processes take place in a confined space containing highly concentrated bioscavengers. The article deals with historical and theoretical backgrounds about enzymatic detoxification of OPs in nanoreactors, nanoreactor polymeric enveloppes, realizations and advantages over other approaches using bioscavengers.
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Affiliation(s)
- Tatiana N Pashirova
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, Arbuzov str., 8, Kazan, 420088, Russian Federation
| | - Andrei Bogdanov
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, Arbuzov str., 8, Kazan, 420088, Russian Federation
| | - Patrick Masson
- Kazan Federal University, Neuropharmacology Laboratory, Kremlevskaya str., 18, Kazan, 420111, Russian Federation.
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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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Nichols RH, Chambers JE. Reactivation of organophosphate-inhibited serum butyrylcholinesterase by novel substituted phenoxyalkyl pyridinium oximes and traditional oximes. Toxicology 2021; 452:152719. [PMID: 33592259 DOI: 10.1016/j.tox.2021.152719] [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: 12/23/2020] [Revised: 01/30/2021] [Accepted: 02/09/2021] [Indexed: 10/22/2022]
Abstract
Organophosphorus compounds (OPs) include nerve agents and insecticides that potently inhibit acetylcholinesterase (AChE), an essential enzyme found throughout the nervous system. High exposure levels to OPs lead to seizures, cardiac arrest, and death if left untreated. Oximes are a critical piece to the therapeutic regimen which remove the OP from the inhibited AChE and restore normal cholinergic function. The current oximes 2-PAM, MMB-4, TMB-4, HI-6, and obidoxime (OBD) have two drawbacks: lack of broad spectrum protection against multiple OP structures and poor brain penetration to protect against OP central neurotoxicity. An alternative strategy to enhance therapy is reactivation of serum butyrylcholinesterase (BChE). BChE is stoichiometrically inhibited by OPs with no apparent toxic result. Inhibition of BChE in the serum followed by reactivation could create a pseudo-catalytic scavenger allowing numerous regenerations of BChE to detoxify circulating OP molecules before they can reach target AChE. BChE in serum from rats, guinea pigs or humans was screened for the reactivation potential of our novel substituted phenoxyalkyl pyridinium oximes, plus 2-PAM, MMB-4, TMB-4, HI-6, and OBD (100μM) in vitro after inhibition by highly relevant surrogates of sarin, VX, and cyclosarin, and also DFP, and the insecticidal active metabolites paraoxon, phorate-oxon, and phorate-oxon sulfoxide. Novel oxime 15 demonstrated significant broad spectrum reactivation of OP-inhibited rat serum BChE while novel oxime 20 demonstrated significant broad spectrum reactivation of OP-inhibited human serum BChE. All tested oximes were poor reactivators of OP-inhibited guinea pig serum BChE. The bis-pyridinium oximes were poor BChE reactivators overall. BChE reactivation may be an additional mechanism to attenuate OP toxicity and contribute to therapeutic efficacy.
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Affiliation(s)
- Royce H Nichols
- Center for Environmental Health Sciences, College of Veterinary Medicine, Mississippi State University, MS, 39762, United States
| | - Janice E Chambers
- Center for Environmental Health Sciences, College of Veterinary Medicine, Mississippi State University, MS, 39762, United States.
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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: 47] [Impact Index Per Article: 11.8] [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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Multiscale computation delivers organophosphorus reactivity and stereoselectivity to immunoglobulin scavengers. Proc Natl Acad Sci U S A 2020; 117:22841-22848. [PMID: 32859757 PMCID: PMC7502716 DOI: 10.1073/pnas.2010317117] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Developed quantum mechanics/molecular mechanics (QM/MM) supercomputation is used to identify maturation of immunoglobulin (Ig) reactivity through optimization of amino acids in the catalytic core, focused on enhanced nucleophilic attack on phosphorus. A computationally optimized variant, l-Leu47Lys, delivers 340-fold reactivity enhancement for paraoxon relative to wild-type Ig-paraoxonase resulting from substrate-induced ionization of the Tyr37 nucleophile. Variant antibody stereoselectivity toward a P-chiral phenylphosphonate toxin results from starkly contrasting solvent-assisted or general base catalytic mechanisms relative to the parent Ig-paraoxonase. These mechanisms are defined by crystallographic and QM/MM analyses as resulting from changed substrate orientation and participating amino acid conformations within the catalytic site. Quantum mechanics/molecular mechanics (QM/MM) maturation of an immunoglobulin (Ig) powered by supercomputation delivers novel functionality to this catalytic template and facilitates artificial evolution of biocatalysts. We here employ density functional theory-based (DFT-b) tight binding and funnel metadynamics to advance our earlier QM/MM maturation of A17 Ig-paraoxonase (WTIgP) as a reactibody for organophosphorus toxins. It enables regulation of biocatalytic activity for tyrosine nucleophilic attack on phosphorus. The single amino acid substitution l-Leu47Lys results in 340-fold enhanced reactivity for paraoxon. The computed ground-state complex shows substrate-induced ionization of the nucleophilic l-Tyr37, now H-bonded to l-Lys47, resulting from repositioning of l-Lys47. Multiple antibody structural homologs, selected by phenylphosphonate covalent capture, show contrasting enantioselectivities for a P-chiral phenylphosphonate toxin. That is defined by crystallographic analysis of phenylphosphonylated reaction products for antibodies A5 and WTIgP. DFT-b analysis using QM regions based on these structures identifies transition states for the favored and disfavored reactions with surprising results. This stereoselection analysis is extended by funnel metadynamics to a range of WTIgP variants whose predicted stereoselectivity is endorsed by experimental analysis. The algorithms used here offer prospects for tailored design of highly evolved, genetically encoded organophosphorus scavengers and for broader functionalities of members of the Ig superfamily, including cell surface-exposed receptors.
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Hayes TR, Blecha JE, Chao CK, Huynh TL, VanBrocklin HF, Zinn KR, Taylor PW, Gerdes JM, Thompson CM. Positron emission tomography evaluation of oxime countermeasures in live rats using the tracer O-(2-[ 18 F]fluoroethyl)-O-(p-nitrophenyl)methylphosphonate [ 18 F]-VXS. Ann N Y Acad Sci 2020; 1479:180-195. [PMID: 32436233 DOI: 10.1111/nyas.14363] [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: 01/24/2020] [Revised: 04/13/2020] [Accepted: 04/17/2020] [Indexed: 11/27/2022]
Abstract
Oxime antidotes regenerate organophosphate-inhibited acetylcholinesterase (AChE). Although they share a common mechanism of AChE reactivation, the rate and amount of oxime that enters the brain are critical to the efficacy, a process linked to the oxime structure and charge. Using a platform based on the organophosphate [18 F]-VXS as a positron emission tomography tracer for active AChE, the in vivo distribution of [18 F]-VXS was evaluated after an LD50 dose (250 μg/kg) of the organophosphate paraoxon (POX) and following oximes as antidotes. Rats given [18 F]-VXS tracer alone had significantly higher radioactivity (two- to threefold) in the heart and lung than rats given LD50 POX at 20 or 60 min prior to [18 F]-VXS. When rats were given LD50 POX followed by 2-PAM (cationic), RS194b (ionizable), or monoisonitrosoacetone (MINA) (neutral), central nervous system (CNS) radioactivity returned to levels at or above untreated naive rats (no POX), whereas CNS radioactivity did not increase in rats given the dication oximes HI-6 or MMB-4. MINA showed a significant, pairwise increase in CNS brain radioactivity compared with POX-treated rats. This new in vivo dynamic platform using [18 F]-VXS tracer measures and quantifies peripheral and CNS relative changes in AChE availability after POX exposure and is suitable for comparing oxime delivery and AChE reactivation in rats.
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Affiliation(s)
- Thomas R Hayes
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
| | - Joseph E Blecha
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
| | - Chih-Kai Chao
- Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, Montana
| | - Tony L Huynh
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
| | - Henry F VanBrocklin
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
| | - Kurt R Zinn
- Departments of Radiology, Small Animal Clinical Sciences, and Biomedical Engineering, Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, Michigan
| | - Palmer W Taylor
- Department of Pharmacology, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California at San Diego, La Jolla, California
| | - John M Gerdes
- Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, Montana
| | - Charles M Thompson
- Department of Biomedical and Pharmaceutical Sciences, University of Montana, Missoula, Montana
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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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Makhaeva GF, Rudakova EV, Kovaleva NV, Lushchekina SV, Boltneva NP, Proshin AN, Shchegolkov EV, Burgart YV, Saloutin VI. Cholinesterase and carboxylesterase inhibitors as pharmacological agents. Russ Chem Bull 2019. [DOI: 10.1007/s11172-019-2507-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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16
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Grigorenko BL, Novichkova DA, Lushchekina SV, Zueva IV, Schopfer LM, Nemukhin AV, Varfolomeev SD, Lockridge O, Masson P. Computer-designed active human butyrylcholinesterase double mutant with a new catalytic triad. Chem Biol Interact 2019; 306:138-146. [PMID: 31009643 DOI: 10.1016/j.cbi.2019.04.019] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Revised: 04/04/2019] [Accepted: 04/15/2019] [Indexed: 01/05/2023]
Abstract
A computer-designed mutant of human butyrylcholinesterase (BChE), N322E/E325G, with a novel catalytic triad was made. The catalytic triad of the wild-type enzyme (S198·H438·E325) was replaced by S198·H438·N322E in silico. Molecular dynamics for 1.5 μs and Markov state model analysis showed that the new catalytic triad should be operative in the mutant enzyme, suggesting functionality. QM/MM modeling performed for the reaction of wild-type BChE and double mutant with echothiophate showed high reactivity of the mutant towards the organophosphate. A truncated monomeric (L530 stop) double mutant was expressed in Expi293 cells. Non-purified transfected cell culture medium was analyzed. Polyacrylamide gel electrophoresis under native conditions followed by activity staining with BTC as the substrate provided evidence that the monomeric BChE mutant was active. Inhibition of the double mutant by echothiophate followed by polyacrylamide gel electrophoresis and activity staining showed that this enzyme slowly self-reactivated. However, because Expi293 cells secrete an endogenous BChE tetramer and several organophosphate-reacting enzymes, catalytic parameters and self-reactivation constants after phosphorylation of the new mutant were not determined in the crude cell culture medium. The study shows that the computer-designed double mutant (N322E/E325G) with a new catalytic triad (S198·H438·N322E) is a suitable template for design of novel active human BChE mutants that display an organophosphate hydrolase activity.
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Affiliation(s)
- Bella L Grigorenko
- N.M. Emanuel Institute of Biochemical Physics of Russian Academy of Sciences, Kosygina Str. 4, Moscow 119334, Russia; Lomonosov State University, Chemistry Department, Moscow 119991, Russia
| | - Dana A Novichkova
- N.M. Emanuel Institute of Biochemical Physics of Russian Academy of Sciences, Kosygina Str. 4, Moscow 119334, Russia
| | - Sofya V Lushchekina
- N.M. Emanuel Institute of Biochemical Physics of Russian Academy of Sciences, Kosygina Str. 4, Moscow 119334, Russia.
| | - Irina V Zueva
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center of RAS, Arbuzov Str. 8, Kazan, 420088, Russia; Kazan Federal University, Neuropharmacology Laboratory, Kremlevskaya Str, 18, Kazan, 420008, Russia
| | - Lawrence M Schopfer
- Eppley Institute, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Alexander V Nemukhin
- N.M. Emanuel Institute of Biochemical Physics of Russian Academy of Sciences, Kosygina Str. 4, Moscow 119334, Russia; Lomonosov State University, Chemistry Department, Moscow 119991, Russia
| | - Sergey D Varfolomeev
- N.M. Emanuel Institute of Biochemical Physics of Russian Academy of Sciences, Kosygina Str. 4, Moscow 119334, Russia; Lomonosov State University, Chemistry Department, Moscow 119991, Russia
| | - Oksana Lockridge
- Eppley Institute, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Patrick Masson
- Kazan Federal University, Neuropharmacology Laboratory, Kremlevskaya Str, 18, Kazan, 420008, Russia.
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Timperley CM, Abdollahi M, Al-Amri AS, Baulig A, Benachour D, Borrett V, Cariño FA, Geist M, Gonzalez D, Kane W, Kovarik Z, Martínez-Álvarez R, Fusaro Mourão NM, Neffe S, Raza SK, Rubaylo V, Suárez AG, Takeuchi K, Tang C, Trifirò F, van Straten FM, Vanninen PS, Vučinić S, Zaitsev V, Zafar-Uz-Zaman M, Zina MS, Holen S, Forman JE, Alwan WS, Suri V. Advice on assistance and protection by the Scientific Advisory Board of the Organisation for the Prohibition of Chemical Weapons: Part 2. On preventing and treating health effects from acute, prolonged, and repeated nerve agent exposure, and the identification of medical countermeasures able to reduce or eliminate the longer term health effects of nerve agents. Toxicology 2019; 413:13-23. [DOI: 10.1016/j.tox.2018.11.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 11/18/2018] [Accepted: 11/26/2018] [Indexed: 01/08/2023]
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Lushchekina S, Masson P. Catalytic bioscavengers against organophosphorus agents: mechanistic issues of self-reactivating cholinesterases. Toxicology 2018; 409:91-102. [DOI: 10.1016/j.tox.2018.07.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 07/23/2018] [Accepted: 07/25/2018] [Indexed: 12/21/2022]
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Wan X, Yao Y, Fang L, Liu J. Unexpected protonation state of Glu197 discovered from simulations of tacrine in butyrylcholinesterase. Phys Chem Chem Phys 2018; 20:14938-14946. [PMID: 29786716 DOI: 10.1039/c8cp01566j] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Butyrylcholinesterase (BChE) has been actively involved in drug discoveries from many fields for decades. In the crystal structure of the BChE-tacrine complex, there is an unanticipated formyl-proline molecule resolved very close to tacrine, raising an essential question on how reliable it is to apply the binding pose in a crystal structure to analyze related experimental observations, in which no formyl-proline is actually involved. In this study, by performing a series of 100 ns molecular dynamics simulations, we demonstrate that it is safe to employ the structural information from this crystal structure to analyze related experimental observations. Surprisingly, Glu197 needs to be protonated to have the structures simulated appropriately. It should be noted that Glu197 has been commonly considered as deprotonated in diverse analyses due to its low pKa in aqueous solution, for which some interpretations are inconsistent or unclear. Our further investigation shows that the protonated Glu197 plays a very important role in preserving His438 within the catalytic triad through stabilizing a highly conserved water molecule. Interestingly, the catalytic triad and Glu197 have been long recognized for possibly deviating largely from the crystal structure, which might be catalytically deficient and is generally considered to result from the difference between the crystal and aqueous environment. Herein, our results suggest that the large deviations of the catalytic triad and Glu197 from the crystal structure are caused by the inappropriate protonation state of Glu197. This finding shall provide an important clue that has been long missing for a better understanding of BChE-related puzzles or even reconsideration of some BChE-catalyzed reaction mechanisms.
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Affiliation(s)
- Xiao Wan
- School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, Hubei 430030, P. R. China.
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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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Ghodge SV, Raushel FM. Structure, Mechanism, and Substrate Profiles of the Trinuclear Metallophosphatases from the Amidohydrolase Superfamily. Methods Enzymol 2018; 607:187-216. [PMID: 30149858 DOI: 10.1016/bs.mie.2018.04.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The rate of reliable protein function annotation has not kept pace with the rapid advances in genome sequencing technology. This has created a gap between the number of available protein sequences, and an accurate determination of the respective physiological functions. This investigation has attempted to bridge the gap within the confines of members of the polymerase and histidinol phosphatase family of proteins in cog1387 and cog0613, which is related to the amidohydrolase superfamily. The adopted approach relies on using the mechanistic knowledge of a known enzymatic reaction, and discovering functions of closely related homologs using various tools including bioinformatics and rational library screening. The initial enzymatic reaction was that of L-histidinol phosphate phosphatase. Extensive structural, biochemical, and bioinformatic analysis of enzymes capable of hydrolyzing L-histidinol phosphate provided useful insights in predicting substrates and mechanistic studies of related enzymes. This led to the discovery of unprecedented catalytic functions such as a cyclic phosphate dihydrolase that specifically hydrolyzed a cyclic phosphodiester to inorganic phosphate and a vicinal diol; a phosphoesterase that hydrolyzes the 3'-phosphate of 3',5'-adenosine bisphosphate and similar nucleotides; and the first reported 5'-3' exonuclease for 5'-phosphorylated oligonucleotides from Escherichia coli and related organisms. This work provides a template for developing sequence-structure-function correlations within a family of enzymes that helps expedite new enzyme function discovery and more accurate annotations in protein databases.
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Affiliation(s)
- Swapnil V Ghodge
- Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Frank M Raushel
- Department of Chemistry, Texas A & M University, College Station, TX, United States.
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Costanzi S, Machado JH, Mitchell M. Nerve Agents: What They Are, How They Work, How to Counter Them. ACS Chem Neurosci 2018; 9:873-885. [PMID: 29664277 DOI: 10.1021/acschemneuro.8b00148] [Citation(s) in RCA: 99] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Nerve agents are organophosphorus chemical warfare agents that exert their action through the irreversible inhibition of acetylcholinesterase, with a consequent overstimulation of cholinergic transmission followed by its shutdown. Beyond warfare, they have notoriously been employed in acts of terrorism as well as high profile assassinations. After a brief historical introduction on the development and deployment of nerve agents, this review provides a survey of their chemistry, the way they affect cholinergic transmission, the available treatment options, and the current directions for their improvement. As the review illustrates, despite their merits, the currently available treatment options present several shortcomings. Current research directions involve the search for improved antidotes, antagonists of the nicotinic receptors, small-molecule pretreatment options, as well as bioscavengers as macromolecular pretreatment options. These efforts are making good progress in many different directions and, hopefully, will lead to a lower target susceptibility, thus reducing the appeal of nerve agents as chemical weapons.
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Affiliation(s)
| | - John-Hanson Machado
- Department of Chemistry, The George Washington University, 800 22nd Street NW, Washington, DC 20052, United States
- Computational Biology Institute, The George Washington University, 45085 University Drive Suite 305, Ashburn, Virginia 20147, United States
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Restaino OF, Borzacchiello MG, Scognamiglio I, Fedele L, Alfano A, Porzio E, Manco G, De Rosa M, Schiraldi C. High yield production and purification of two recombinant thermostable phosphotriesterase-like lactonases from Sulfolobus acidocaldarius and Sulfolobus solfataricus useful as bioremediation tools and bioscavengers. BMC Biotechnol 2018; 18:18. [PMID: 29558934 PMCID: PMC5861644 DOI: 10.1186/s12896-018-0427-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 03/09/2018] [Indexed: 02/01/2023] Open
Abstract
Background Thermostable phosphotriesterase-like lactonases (PLLs) are able to degrade organophosphates and could be potentially employed as bioremediation tools and bioscavengers. But nowadays their manufacturing in high yields is still an issue that limits their industrial applications. In this work we aimed to set up a high yield production and purification biotechnological process of two recombinant PLLs expressed in E. coli, the wild type SacPox from Sulfolobus acidocaldarius and a triple mutated SsoPox C258L/I261F/W263A, originally from Sulfolobus solfataricus. To follow this aim new induction approaches were investigated to boost the enzyme production, high cell density fermentation strategies were set-up to reach higher and higher enzyme yields up to 22-L scale, a downstream train was studied to meet the requirements of an efficient industrial purification process. Results Physiological studies in shake flasks demonstrated that the use of galactose as inducer increased the enzyme concentrations up to 4.5 folds, compared to the production obtained by induction with IPTG. Optimising high cell density fed-batch strategies the production and the productivity of both enzymes were further enhanced of 26 folds, up to 2300 U·L− 1 and 47.1 U·L− 1·h− 1 for SacPox and to 8700 U·L− 1 and 180.6 U·L− 1·h− 1 for SsoPox C258L/I261F/W263A, and the fermentation processes resulted scalable from 2.5 to 22.0 L. After being produced and extracted from the cells, the enzymes were first purified by a thermo-precipitation step, whose conditions were optimised by response surface methodology. A following ultra-filtration process on 100 and 5 KDa cut-off membranes drove to a final pureness and a total recovery of both enzymes of 70.0 ± 2.0%, suitable for industrial applications. Conclusions In this paper, for the first time, a high yield biotechnological manufacturing process of the recombinant enzymes SacPox and SsoPox C258L/I261F/W263A was set-up. The enzyme production was boosted by combining a new galactose induction approach with high cell density fed-batch fermentation strategies. An efficient enzyme purification protocol was designed coupling a thermo-precipitation step with a following membrane-based ultra-filtration process. Electronic supplementary material The online version of this article (10.1186/s12896-018-0427-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Odile Francesca Restaino
- Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, University of Campania "Luigi Vanvitelli"-ex Second University of Naples, Naples, Italy.
| | - Maria Giovanna Borzacchiello
- Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, University of Campania "Luigi Vanvitelli"-ex Second University of Naples, Naples, Italy
| | - Ilaria Scognamiglio
- Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, University of Campania "Luigi Vanvitelli"-ex Second University of Naples, Naples, Italy
| | - Luigi Fedele
- Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, University of Campania "Luigi Vanvitelli"-ex Second University of Naples, Naples, Italy
| | - Alberto Alfano
- Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, University of Campania "Luigi Vanvitelli"-ex Second University of Naples, Naples, Italy
| | - Elena Porzio
- Institute of Protein Biochemistry, National Research Council of Italy, Naples, Italy
| | - Giuseppe Manco
- Institute of Protein Biochemistry, National Research Council of Italy, Naples, Italy
| | - Mario De Rosa
- Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, University of Campania "Luigi Vanvitelli"-ex Second University of Naples, Naples, Italy
| | - Chiara Schiraldi
- Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, University of Campania "Luigi Vanvitelli"-ex Second University of Naples, Naples, Italy
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Lushchekina SV, Schopfer LM, Grigorenko BL, Nemukhin AV, Varfolomeev SD, Lockridge O, Masson P. Optimization of Cholinesterase-Based Catalytic Bioscavengers Against Organophosphorus Agents. Front Pharmacol 2018; 9:211. [PMID: 29593539 PMCID: PMC5859046 DOI: 10.3389/fphar.2018.00211] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Accepted: 02/26/2018] [Indexed: 11/13/2022] Open
Abstract
Organophosphorus agents (OPs) are irreversible inhibitors of acetylcholinesterase (AChE). OP poisoning causes major cholinergic syndrome. Current medical counter-measures mitigate the acute effects but have limited action against OP-induced brain damage. Bioscavengers are appealing alternative therapeutic approach because they neutralize OPs in bloodstream before they reach physiological targets. First generation bioscavengers are stoichiometric bioscavengers. However, stoichiometric neutralization requires administration of huge doses of enzyme. Second generation bioscavengers are catalytic bioscavengers capable of detoxifying OPs with a turnover. High bimolecular rate constants (kcat/Km > 106 M−1min−1) are required, so that low enzyme doses can be administered. Cholinesterases (ChE) are attractive candidates because OPs are hemi-substrates. Moderate OP hydrolase (OPase) activity has been observed for certain natural ChEs and for G117H-based human BChE mutants made by site-directed mutagenesis. However, before mutated ChEs can become operational catalytic bioscavengers their dephosphylation rate constant must be increased by several orders of magnitude. New strategies for converting ChEs into fast OPase are based either on combinational approaches or on computer redesign of enzyme. The keystone for rational conversion of ChEs into OPases is to understand the reaction mechanisms with OPs. In the present work we propose that efficient OP hydrolysis can be achieved by re-designing the configuration of enzyme active center residues and by creating specific routes for attack of water molecules and proton transfer. Four directions for nucleophilic attack of water on phosphorus atom were defined. Changes must lead to a novel enzyme, wherein OP hydrolysis wins over competing aging reactions. Kinetic, crystallographic, and computational data have been accumulated that describe mechanisms of reactions involving ChEs. From these studies, it appears that introducing new groups that create a stable H-bonded network susceptible to activate and orient water molecule, stabilize transition states (TS), and intermediates may determine whether dephosphylation is favored over aging. Mutations on key residues (L286, F329, F398) were considered. QM/MM calculations suggest that mutation L286H combined to other mutations favors water attack from apical position. However, the aging reaction is competing. Axial direction of water attack is not favorable to aging. QM/MM calculation shows that F329H+F398H-based multiple mutants display favorable energy barrier for fast reactivation without aging.
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Affiliation(s)
- Sofya V Lushchekina
- Laboratory of Computer Modeling of Bimolecular Systems and Nanomaterials, N. M. Emanuel Institute of Biochemical Physics of Russian Academy of Sciences, Moscow, Russia
| | - Lawrence M Schopfer
- Department of Biochemistry and Molecular Biology, Eppley Institute, University of Nebraska Medical Center, Omaha, NE, United States
| | - Bella L Grigorenko
- Laboratory of Computer Modeling of Bimolecular Systems and Nanomaterials, N. M. Emanuel Institute of Biochemical Physics of Russian Academy of Sciences, Moscow, Russia.,Chemistry Department, Lomonosov State University, Moscow, Russia
| | - Alexander V Nemukhin
- Laboratory of Computer Modeling of Bimolecular Systems and Nanomaterials, N. M. Emanuel Institute of Biochemical Physics of Russian Academy of Sciences, Moscow, Russia.,Chemistry Department, Lomonosov State University, Moscow, Russia
| | - Sergei D Varfolomeev
- Laboratory of Computer Modeling of Bimolecular Systems and Nanomaterials, N. M. Emanuel Institute of Biochemical Physics of Russian Academy of Sciences, Moscow, Russia.,Chemistry Department, Lomonosov State University, Moscow, Russia
| | - Oksana Lockridge
- Department of Biochemistry and Molecular Biology, Eppley Institute, University of Nebraska Medical Center, Omaha, NE, United States
| | - Patrick Masson
- Neuropharmacology Laboratory, Kazan Federal University, Kazan, Russia
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Masson P, Nachon F. Cholinesterase reactivators and bioscavengers for pre- and post-exposure treatments of organophosphorus poisoning. J Neurochem 2017; 142 Suppl 2:26-40. [PMID: 28542985 DOI: 10.1111/jnc.14026] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 03/02/2017] [Accepted: 03/10/2017] [Indexed: 12/11/2022]
Abstract
Organophosphorus agents (OPs) irreversibly inhibit acetylcholinesterase (AChE) causing a major cholinergic syndrome. The medical counter-measures of OP poisoning have not evolved for the last 30 years with carbamates for pretreatment, pyridinium oximes-based AChE reactivators, antimuscarinic drugs and neuroprotective benzodiazepines for post-exposure treatment. These drugs ensure protection of peripheral nervous system and mitigate acute effects of OP lethal doses. However, they have significant limitations. Pyridostigmine and oximes do not protect/reactivate central AChE. Oximes poorly reactivate AChE inhibited by phosphoramidates. In addition, current neuroprotectants do not protect the central nervous system shortly after the onset of seizures when brain damage becomes irreversible. New therapeutic approaches for pre- and post-exposure treatments involve detoxification of OP molecules before they reach their molecular targets by administrating catalytic bioscavengers, among them phosphotriesterases are the most promising. Novel generation of broad spectrum reactivators are designed for crossing the blood-brain barrier and reactivate central AChE. This is an article for the special issue XVth International Symposium on Cholinergic Mechanisms.
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Affiliation(s)
- Patrick Masson
- Neuropharmacology Laboratory, Kazan Federal University, Kazan, Russia
| | - Florian Nachon
- Institut de Recherche Biomédicale des Armées, Brétigny-sur-Orge, Cédex, France
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Poirier L, Jacquet P, Elias M, Daudé D, Chabrière E. [Decontamination of organophosphorus compounds: Towards new alternatives]. ANNALES PHARMACEUTIQUES FRANÇAISES 2017; 75:209-226. [PMID: 28267954 DOI: 10.1016/j.pharma.2017.01.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 01/16/2017] [Accepted: 01/24/2017] [Indexed: 01/20/2023]
Abstract
Organophosphorus coumpounds (OP) are toxic chemicals mainly used for agricultural purpose such as insecticides and were also developed and used as warfare nerve agents. OP are inhibitors of acetylcholinesterase, a key enzyme involved in the regulation of the central nervous system. Chemical, physical and biological approaches have been considered to decontaminate OP. This review summarizes the current and emerging strategies that are investigated to tackle this issue with a special emphasis on enzymatic remediation methods. During the last decade, many studies have been dedicated to the development of biocatalysts for OP removal. Among these, recent reports have pointed out the promising enzyme SsoPox isolated from the archaea Sulfolobus solfataricus. Considering both its intrinsic stability and activity, this hyperthermostable enzyme is highly appealing for the decontamination of OP.
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Affiliation(s)
- L Poirier
- Inserm, CNRS, IRD, URMITE, Aix Marseille université, Marseille, France
| | - P Jacquet
- Inserm, CNRS, IRD, URMITE, Aix Marseille université, Marseille, France
| | - M Elias
- Department of Biochemistry, Molecular Biology and Biophysics & Biotechnology Institute, University of Minnesota, St. Paul, MN 55108, États-Unis
| | - D Daudé
- Gene&GreenTK, faculté de médecine, 27, boulevard Jean-Moulin, 13385 Marseille cedex 5, France.
| | - E Chabrière
- Inserm, CNRS, IRD, URMITE, Aix Marseille université, Marseille, France; Gene&GreenTK, faculté de médecine, 27, boulevard Jean-Moulin, 13385 Marseille cedex 5, France.
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Yun H, Yu J, Kim S, Lee N, Lee J, Lee S, Kim ND, Yu C, Rho J. Expression and purification of biologically active recombinant human paraoxonase 1 from a Drosophila S2 stable cell line. Protein Expr Purif 2017; 131:34-41. [DOI: 10.1016/j.pep.2016.11.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 11/01/2016] [Accepted: 11/08/2016] [Indexed: 01/03/2023]
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Molecular polymorphism of human enzymes as the basis of individual sensitivity to drugs. Supercomputer-assisted modeling as a tool for analysis of structural changes and enzymatic activity of proteins. Russ Chem Bull 2017. [DOI: 10.1007/s11172-016-1487-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Characterization of butyrylcholinesterase in bovine serum. Chem Biol Interact 2017; 266:17-27. [PMID: 28189703 DOI: 10.1016/j.cbi.2017.02.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 01/25/2017] [Accepted: 02/07/2017] [Indexed: 02/07/2023]
Abstract
Human butyrylcholinesterase (HuBChE) protects from nerve agent toxicity. Our goal was to determine whether bovine serum could be used as a source of BChE. Bovine BChE (BoBChE) was immunopurified from 100 mL fetal bovine serum (FBS) or 380 mL adult bovine serum by binding to immobilized monoclonal mAb2. Bound proteins were digested with trypsin and analyzed by liquid chromatography-tandem mass spectrometry. The results proved that FBS and adult bovine serum contain BoBChE. The concentration of BoBChE was estimated to be 0.04 μg/mL in FBS, and 0.03 μg/mL in adult bovine serum, values lower than the 4 μg/mL BChE in human serum. Nondenaturing gel electrophoresis showed that monoclonal mAb2 bound BoBChE but not bovine acetylcholinesterase (BoAChE) and confirmed that FBS contains BoBChE and BoAChE. Recombinant bovine BChE (rBoBChE) expressed in serum-free culture medium spontaneously reactivated from inhibition by chlorpyrifos oxon at a rate of 0.0023 min-1 (t1/2 = 301 min-1) and aged at a rate of 0.0138 min-1 (t1/2 = 50 min-1). Both BoBChE and HuBChE have 574 amino acids per subunit and 90% sequence identity. However, the apparent size of serum BoBChE and rBoBChE tetramers was much greater than the 340,000 Da of HuBChE tetramers. Whereas HuBChE tetramers include short polyproline rich peptides derived from lamellipodin, no polyproline peptides have been identified in BoBChE. We hypothesize that BoBChE tetramers use a large polyproline-rich protein to organize subunits into a tetramer and that the low concentration of BoBChE in serum is explained by limited quantities of an unidentified polyproline-rich protein.
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31
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Restaino OF, Borzacchiello MG, Scognamiglio I, Porzio E, Manco G, Fedele L, Donatiello C, De Rosa M, Schiraldi C. Boosted large-scale production and purification of a thermostable archaeal phosphotriesterase-like lactonase for organophosphate decontamination. J Ind Microbiol Biotechnol 2017; 44:363-375. [PMID: 28074318 DOI: 10.1007/s10295-016-1892-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 12/22/2016] [Indexed: 10/20/2022]
Abstract
Thermostable phosphotriesterase-like lactonases (PLLs) from extremophile archaea, like SsoPox from Sulfolobus solfataricus, are attractive biotechnological tools with industrial applications as organophosphate decontaminants, but their manufacturing still remains an unresolved issue because of the high costs and the low production yields. In this paper, for the first time, an efficient biotechnological process for the production and purification of a recombinant, engineered PLL, SsoPox W263F, expressed in E. coli, has been set up by studying new induction strategies, by designing high cell density cultivations and a new membrane-based downstream process. In fed batches, the enzyme production was boosted of 69-fold up to 4660.0 U L-1 using galactose as inducer in the replacement of IPTG; the process was scalable from 2.5 up to 150 L. By coupling a single thermo-precipitation step and an ultrafiltration process, a total enzyme recovery of 77% with a purity grade of almost 80% was reached.
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Affiliation(s)
- Odile Francesca Restaino
- Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, Second University of Naples, Naples, Italy.
| | - Maria Giovanna Borzacchiello
- Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, Second University of Naples, Naples, Italy
| | - Ilaria Scognamiglio
- Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, Second University of Naples, Naples, Italy
| | - Elena Porzio
- Institute of Protein Biochemistry, National Research Council of Italy, Naples, Italy
| | - Giuseppe Manco
- Institute of Protein Biochemistry, National Research Council of Italy, Naples, Italy
| | - Luigi Fedele
- Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, Second University of Naples, Naples, Italy
| | - Cinzia Donatiello
- Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, Second University of Naples, Naples, Italy
| | - Mario De Rosa
- Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, Second University of Naples, Naples, Italy
| | - Chiara Schiraldi
- Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, Second University of Naples, Naples, Italy.
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Langston JL, Myers TM. VX toxicity in the Göttingen minipig. Toxicol Lett 2016; 264:12-19. [PMID: 27773723 DOI: 10.1016/j.toxlet.2016.10.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 09/20/2016] [Accepted: 10/19/2016] [Indexed: 11/18/2022]
Abstract
The present experiments determined the intramuscular LD50 of VX in male Göttingen minipigs at two stages of development. In pubertal animals (115 days old), the LD50 of VX was indeterminate, but approximated 33.3μg/kg. However, in sexually mature animals (152 days old), the LD50 was estimated to be only 17.4μg/kg. Signs of nerve agent toxicity in the Göttingen minipig were similar to those described for other species, with some notable exceptions (such as urticaria and ejaculation). Latencies to the onset of sustained convulsions were inversely related to the administered dose of VX in both ages of minipigs. Additionally, actigraphy was used to quantify the presence of tremor and convulsions and, in some cases, was useful for precisely estimating time of death. The main finding indicates that in minipigs, as in other species, even relatively small differences in age can substantially alter the toxicity of nerve agents. Additionally, actigraphy can serve as a non-invasive method of characterizing the tremors and convulsions that often accompany nerve agent intoxication.
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Affiliation(s)
- Jeffrey L Langston
- Analytical Toxicology Division, United States Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, MD, USA
| | - Todd M Myers
- Analytical Toxicology Division, United States Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, MD, USA.
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Understanding the non-catalytic behavior of human butyrylcholinesterase silent variants: Comparison of wild-type enzyme, catalytically active Ala328Cys mutant, and silent Ala328Asp variant. Chem Biol Interact 2016; 259:223-232. [PMID: 27062896 DOI: 10.1016/j.cbi.2016.04.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Revised: 03/15/2016] [Accepted: 04/04/2016] [Indexed: 11/24/2022]
Abstract
Conformational dynamics of wild-type human butyrylcholinesterase (BChE), two mutants of residue Ala328, the catalytically active Ala328Cys, and the catalytically inactive (silent) Ala328Asp, and their interactions with butyrylcholine were studied. The aim was to understand the molecular mechanisms by which point mutations may lead to silent BChE variant or alter catalytic activity. Importance of BChE natural variants is due to medical consequences, i.e. prolonged apnea, following administration of the myorelaxant esters, succinylcholine and mivacurium. Comparison of molecular dynamics (MD) simulations for the three model systems showed that: 1) the active mutant Ala328Cys mutant has some changes in configuration of catalytic residues, which do not prevent binding of butyrylcholine to the active site; 2) in the naturally-occurring silent variant Ala328Asp, the Asp328 carboxylate may either form a salt bridge with Lys339 or a H-bond with His438. In the first case, the Ω-loop swings off the gorge, disrupting the π-cation binding site and the catalytic triad. In the second case, binding of cationic substrates in the catalytic center is also impaired. MD simulations carried out in 0.15 M NaCl, close to physiological ionic strength conditions, favored the second situation. It was seen that Asp328 forms a H-bond with the catalytic triad His438, which in turn disrupts the catalytic machinery. Therefore, we concluded that the Ala328Asp variant is not catalytically active because of that dramatic event. Computational results, consistent with in vitro biochemical data and clinical observations, validate our MD approach.
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