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Clay WK, Buck AK, He Y, Hernández Sánchez DN, Ward NA, Lear JM, Nguyen KQ, Clark BH, Sapia RJ, Lalisse RF, Sriraman A, Cadieux CL, McElroy CA, Callam CS, Hadad CM. Treatment of Organophosphorus Poisoning with 6-Alkoxypyridin-3-ol Quinone Methide Precursors: Resurrection of Methylphosphonate-Aged Acetylcholinesterase. Chem Res Toxicol 2024; 37:643-657. [PMID: 38556765 DOI: 10.1021/acs.chemrestox.4c00024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/02/2024]
Abstract
Organophosphorus (OP) nerve agents inhibit acetylcholinesterase (AChE), creating a cholinergic crisis in which death can occur. The phosphylated serine residue spontaneously dealkylates to the OP-aged form, which current therapeutics cannot reverse. Soman's aging half-life is 4.2 min, so immediate recovery (resurrection) of OP-aged AChE is needed. In 2018, we showed pyridin-3-ol-based quinone methide precursors (QMPs) can resurrect OP-aged electric eel AChE in vitro, achieving 2% resurrection after 24 h of incubation (pH 7, 4 mM). We prepared 50 unique 6-alkoxypyridin-3-ol QMPs with 10 alkoxy groups and five amine leaving groups to improve AChE resurrection. These compounds are predicted in silico to cross the blood-brain barrier and treat AChE in the central nervous system. This library resurrected 7.9% activity of OP-aged recombinant human AChE after 24 h at 250 μM, a 4-fold increase from our 2018 report. The best QMP (1b), with a 6-methoxypyridin-3-ol core and a diethylamine leaving group, recovered 20.8% (1 mM), 34% (4 mM), and 42.5% (predicted maximum) of methylphosphonate-aged AChE activity over 24 h. Seven QMPs recovered activity from AChE aged with Soman and a VX degradation product (EA-2192). We hypothesize that QMPs form the quinone methide (QM) to realkylate the phosphylated serine residue as the first step of resurrection. We calculated thermodynamic energetics for QM formation, but there was no trend with the experimental biochemical data. Molecular docking studies revealed that QMP binding to OP-aged AChE is not the determining factor for the observed biochemical trends; thus, QM formation may be enzyme-mediated.
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Affiliation(s)
- William K Clay
- Department of Chemistry and Biochemistry, College of Arts and Sciences, The Ohio State University, Columbus, Ohio 43210, United States
| | - Anne K Buck
- Department of Chemistry and Biochemistry, College of Arts and Sciences, The Ohio State University, Columbus, Ohio 43210, United States
| | - Yiran He
- Department of Chemistry and Biochemistry, College of Arts and Sciences, The Ohio State University, Columbus, Ohio 43210, United States
| | - Dalyanne N Hernández Sánchez
- Department of Chemistry and Biochemistry, College of Arts and Sciences, The Ohio State University, Columbus, Ohio 43210, United States
| | - Nathan A Ward
- Department of Chemistry and Biochemistry, College of Arts and Sciences, The Ohio State University, Columbus, Ohio 43210, United States
| | - Jeremy M Lear
- Department of Chemistry and Biochemistry, College of Arts and Sciences, The Ohio State University, Columbus, Ohio 43210, United States
| | - Kenny Q Nguyen
- Department of Chemistry and Biochemistry, College of Arts and Sciences, The Ohio State University, Columbus, Ohio 43210, United States
| | - Benjamin H Clark
- Department of Chemistry and Biochemistry, College of Arts and Sciences, The Ohio State University, Columbus, Ohio 43210, United States
| | - Ryan J Sapia
- Department of Chemistry and Biochemistry, College of Arts and Sciences, The Ohio State University, Columbus, Ohio 43210, United States
| | - Remy F Lalisse
- Department of Chemistry and Biochemistry, College of Arts and Sciences, The Ohio State University, Columbus, Ohio 43210, United States
| | - Aishwarya Sriraman
- Oak Ridge Institute for Science and Education, 1299 Bethel Valley Road, Oak Ridge, Tennessee 37830, United States
- U.S. Army Medical Research Institute of Chemical Defense, 8350 Ricketts Point Road, Aberdeen Proving Ground, Maryland 21010, United States
| | - C Linn Cadieux
- U.S. Army Medical Research Institute of Chemical Defense, 8350 Ricketts Point Road, Aberdeen Proving Ground, Maryland 21010, United States
| | - Craig A McElroy
- Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, Ohio 43210, United States
| | - Christopher S Callam
- Department of Chemistry and Biochemistry, College of Arts and Sciences, The Ohio State University, Columbus, Ohio 43210, United States
| | - Christopher M Hadad
- Department of Chemistry and Biochemistry, College of Arts and Sciences, The Ohio State University, Columbus, Ohio 43210, United States
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2
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Bennion BJ, Malfatti MA, Be NA, Enright HA, Hok S, Cadieux CL, Carpenter TS, Lao V, Kuhn EA, McNerney MW, Lightstone FC, Nguyen TH, Valdez CA. Development of a CNS-permeable reactivator for nerve agent exposure: an iterative, multi-disciplinary approach. Sci Rep 2021; 11:15567. [PMID: 34330964 PMCID: PMC8324913 DOI: 10.1038/s41598-021-94963-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 07/19/2021] [Indexed: 11/09/2022] Open
Abstract
Nerve agents have experienced a resurgence in recent times with their use against civilian targets during the attacks in Syria (2012), the poisoning of Sergei and Yulia Skripal in the United Kingdom (2018) and Alexei Navalny in Russia (2020), strongly renewing the importance of antidote development against these lethal substances. The current standard treatment against their effects relies on the use of small molecule-based oximes that can efficiently restore acetylcholinesterase (AChE) activity. Despite their efficacy in reactivating AChE, the action of drugs like 2-pralidoxime (2-PAM) is primarily limited to the peripheral nervous system (PNS) and, thus, provides no significant protection to the central nervous system (CNS). This lack of action in the CNS stems from their ionic nature that, on one end makes them very powerful reactivators and on the other renders them ineffective at crossing the Blood Brain Barrier (BBB) to reach the CNS. In this report, we describe the use of an iterative approach composed of parallel chemical and in silico syntheses, computational modeling, and a battery of detailed in vitro and in vivo assays that resulted in the identification of a promising, novel CNS-permeable oxime reactivator. Additional experiments to determine acute and chronic toxicity are ongoing.
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Affiliation(s)
- Brian J Bennion
- Biosciences and Biotechnology Division, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA
| | - Michael A Malfatti
- Biosciences and Biotechnology Division, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA
| | - Nicholas A Be
- Biosciences and Biotechnology Division, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA
| | - Heather A Enright
- Biosciences and Biotechnology Division, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA
| | - Saphon Hok
- Nuclear and Chemical Sciences Division, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA
- Forensic Science Center, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA
| | - C Linn Cadieux
- United States Army Medical Research Institute of Chemical Defense, Aberdeen, MD, 21010, USA
| | - Timothy S Carpenter
- Biosciences and Biotechnology Division, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA
| | - Victoria Lao
- Biosciences and Biotechnology Division, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA
| | - Edward A Kuhn
- Biosciences and Biotechnology Division, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA
| | - M Windy McNerney
- Biosciences and Biotechnology Division, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA
- Affiliation: Mental Illness Research, Education and Clinical Center, Veterans Affairs, Palo Alto, CA, 94304, USA
- Affiliation: Department of Psychiatry, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Felice C Lightstone
- Biosciences and Biotechnology Division, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA
| | - Tuan H Nguyen
- Global Security Directorate, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA
| | - Carlos A Valdez
- Nuclear and Chemical Sciences Division, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA.
- Forensic Science Center, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA.
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3
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Marrero-Rosado BM, Stone MF, de Araujo Furtado M, Schultz CR, Cadieux CL, Lumley LA. Novel Genetically Modified Mouse Model to Assess Soman-Induced Toxicity and Medical Countermeasure Efficacy: Human Acetylcholinesterase Knock-in Serum Carboxylesterase Knockout Mice. Int J Mol Sci 2021; 22:1893. [PMID: 33672922 PMCID: PMC7918218 DOI: 10.3390/ijms22041893] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Revised: 02/06/2021] [Accepted: 02/10/2021] [Indexed: 12/13/2022] Open
Abstract
The identification of improved medical countermeasures against exposure to chemical warfare nerve agents (CWNAs), a class of organophosphorus compounds, is dependent on the choice of animal model used in preclinical studies. CWNAs bind to acetylcholinesterase and prevent the catalysis of acetylcholine, causing a plethora of peripheral and central physiologic manifestations, including seizure. Rodents are widely used to elucidate the effects of CWNA-induced seizure, albeit with a caveat: they express carboxylesterase activity in plasma. Carboxylesterase, an enzyme involved in the detoxification of some organophosphorus compounds, plays a scavenging role and decreases CWNA availability, thus exerting a protective effect. Furthermore, species-specific amino acid differences in acetylcholinesterase confound studies that use oximes or other compounds to restore its function after inhibition by CWNA. The creation of a human acetylcholinesterase knock-in/serum carboxylesterase knockout (C57BL/6-Ces1ctm1.1LocAChEtm1.1Loc/J; a.k.a KIKO) mouse may facilitate better modeling of CWNA toxicity in a small rodent species. The current studies characterize the effects of exposure to soman, a highly toxic CWNA, and evaluate the efficacy of anti-seizure drugs in this newly developed KIKO mouse model. Data demonstrate that a combination of midazolam and ketamine reduces seizure duration and severity, eliminates the development of spontaneous recurrent seizures, and protects certain brain regions from neuronal damage in a genetically modified model with human relevance to organophosphorus compound toxicity. This new animal model and the results of this study and future studies using it will enhance medical countermeasures development for both defense and homeland security purposes.
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Affiliation(s)
- Brenda M. Marrero-Rosado
- Medical Toxicology Research Division, US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, MD 21010, USA; (B.M.M.-R.); (M.F.S.); (C.R.S.); (C.L.C.)
| | - Michael F. Stone
- Medical Toxicology Research Division, US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, MD 21010, USA; (B.M.M.-R.); (M.F.S.); (C.R.S.); (C.L.C.)
| | - Marcio de Araujo Furtado
- Anatomy, Physiology and Genetics Department, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA;
- BioSEaD, LLC, Rockville, MD 20850, USA
| | - Caroline R. Schultz
- Medical Toxicology Research Division, US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, MD 21010, USA; (B.M.M.-R.); (M.F.S.); (C.R.S.); (C.L.C.)
| | - C. Linn Cadieux
- Medical Toxicology Research Division, US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, MD 21010, USA; (B.M.M.-R.); (M.F.S.); (C.R.S.); (C.L.C.)
| | - Lucille A. Lumley
- Medical Toxicology Research Division, US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, MD 21010, USA; (B.M.M.-R.); (M.F.S.); (C.R.S.); (C.L.C.)
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4
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Gupta V, Cadieux CL, McMenamin D, Medina-Jaszek CA, Arif M, Ahonkhai O, Wielechowski E, Taheri M, Che Y, Goode T, Limberis MP, Li M, Cerasoli DM, Tretiakova AP, Wilson JM. Adeno-associated virus-mediated expression of human butyrylcholinesterase to treat organophosphate poisoning. PLoS One 2019; 14:e0225188. [PMID: 31765413 PMCID: PMC6876934 DOI: 10.1371/journal.pone.0225188] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 10/30/2019] [Indexed: 02/05/2023] Open
Abstract
Rare diseases defined by genetic mutations are classic targets for gene therapy. More recently, researchers expanded the use of gene therapy in non-clinical studies to infectious diseases through the delivery of vectorized antibodies to well-defined antigens. Here, we further extend the utility of gene therapy beyond the “accepted” indications to include organophosphate poisoning. There are no approved preventives for the multi-organ damage resulting from acute or chronic exposure to organophosphates. We show that a single intramuscular injection of adeno-associated virus vector produces peak expression (~0.5 mg/ml) of active human butyrylcholinesterase (hBChE) in mice serum within 3–4 weeks post-treatment. This expression is sustained for up to 140 days post-injection with no silencing. Sustained expression of hBChE provided dose-dependent protection against VX in male and female mice despite detectable antibodies to hBChE in some mice, thereby demonstrating that expression of hBChE in vivo in mouse muscle is an effective prophylactic against organophosphate poisoning.
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Affiliation(s)
- Vibhor Gupta
- Gene Therapy Program, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - C. Linn Cadieux
- United States Army Medical Research Institute of Chemical Defense, Maryland, United States of America
| | - Deirdre McMenamin
- Gene Therapy Program, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - C. Angelica Medina-Jaszek
- Gene Therapy Program, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Muhammad Arif
- Gene Therapy Program, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Omua Ahonkhai
- Gene Therapy Program, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Erik Wielechowski
- Gene Therapy Program, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Maryam Taheri
- Gene Therapy Program, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Yan Che
- Gene Therapy Program, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Tamara Goode
- Gene Therapy Program, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Maria P. Limberis
- Gene Therapy Program, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Mingyao Li
- Gene Therapy Program, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- Department of Biostatistics and Epidemiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Douglas M. Cerasoli
- United States Army Medical Research Institute of Chemical Defense, Maryland, United States of America
| | - Anna P. Tretiakova
- Gene Therapy Program, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - James M. Wilson
- Gene Therapy Program, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- * E-mail:
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5
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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] [What about the content of this article? (0)] [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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6
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Dunn EN, Ferrara-Bowens TM, Chachich ME, Honnold CL, Rothwell CC, Hoard-Fruchey HM, Lesyna CA, Johnson EA, Cerasoli DM, McDonough JH, Cadieux CL. Evaluating mice lacking serum carboxylesterase as a behavioral model for nerve agent intoxication. Toxicol Mech Methods 2018; 28:563-572. [PMID: 29768075 DOI: 10.1080/15376516.2018.1476637] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Mice and other rodents are typically utilized for chemical warfare nerve agent research. Rodents have large amounts of carboxylesterase in their blood, while humans do not. Carboxylesterase nonspecifically binds to and detoxifies nerve agent. The presence of this natural bioscavenger makes mice and other rodents poor models for studies identifying therapeutics to treat humans exposed to nerve agents. To obviate this problem, a serum carboxylesterase knockout (Es1 KO) mouse was created. In this study, Es1 KO and wild type (WT) mice were assessed for differences in gene expression, nerve agent (soman; GD) median lethal dose (MLD) values, and behavior prior to and following nerve agent exposure. No expression differences were detected between Es1 KO and WT mice in more than 34 000 mouse genes tested. There was a significant difference between Es1 KO and WT mice in MLD values, as the MLD for GD-exposed WT mice was significantly higher than the MLD for GD-exposed Es1 KO mice. Behavioral assessments of Es1 KO and WT mice included an open field test, a zero maze, a Barnes maze, and a sucrose preference test (SPT). While sex differences were observed in various measures of these tests, overall, Es1 KO mice behaved similarly to WT mice. The two genotypes also showed virtually identical neuropathological changes following GD exposure. Es1 KO mice appear to have an enhanced susceptibility to GD toxicity while retaining all other behavioral and physiological responses to this nerve agent, making the Es1 KO mouse a more human-like model for nerve agent research.
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Affiliation(s)
- Emily N Dunn
- a United States Army Medical Research Institute of Chemical Defense , Aberdeen Proving Ground , MD , USA
| | - Teresa M Ferrara-Bowens
- a United States Army Medical Research Institute of Chemical Defense , Aberdeen Proving Ground , MD , USA
| | - Mark E Chachich
- b Department of Psychology , Towson University , Towson , MD , USA
| | - Cary L Honnold
- a United States Army Medical Research Institute of Chemical Defense , Aberdeen Proving Ground , MD , USA
| | - Cristin C Rothwell
- a United States Army Medical Research Institute of Chemical Defense , Aberdeen Proving Ground , MD , USA
| | - Heidi M Hoard-Fruchey
- a United States Army Medical Research Institute of Chemical Defense , Aberdeen Proving Ground , MD , USA
| | - Catherine A Lesyna
- a United States Army Medical Research Institute of Chemical Defense , Aberdeen Proving Ground , MD , USA
| | - Erik A Johnson
- a United States Army Medical Research Institute of Chemical Defense , Aberdeen Proving Ground , MD , USA
| | - Douglas M Cerasoli
- a United States Army Medical Research Institute of Chemical Defense , Aberdeen Proving Ground , MD , USA
| | - John H McDonough
- a United States Army Medical Research Institute of Chemical Defense , Aberdeen Proving Ground , MD , USA
| | - C Linn Cadieux
- a United States Army Medical Research Institute of Chemical Defense , Aberdeen Proving Ground , MD , USA
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7
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Matson EM, Dillman N, DeBus SJ, Cadieux CL. Development of a Single Reaction PCR Genotyping Assay for Two Separate Gene Loci in Mice. FASEB J 2018. [DOI: 10.1096/fasebj.2018.32.1_supplement.532.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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8
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Cadieux CL, Canter Z, Martin K, Hepperle M, Cerasoli DM. Utilizing Structure‐Activity Relationships to Design Non ‐ Oxime Reactivators. FASEB J 2018. [DOI: 10.1096/fasebj.2018.32.1_supplement.lb79] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- C. Linn Cadieux
- Medical Toxicology DivisionUnited States Army Medical Research Institute of Chemical DefenseAberdeen Proving GroundMD
| | - Zachary Canter
- Medical Toxicology DivisionUnited States Army Medical Research Institute of Chemical DefenseAberdeen Proving GroundMD
| | - Kevin Martin
- Medical Toxicology DivisionUnited States Army Medical Research Institute of Chemical DefenseAberdeen Proving GroundMD
| | - Michael Hepperle
- Medical Toxicology DivisionUnited States Army Medical Research Institute of Chemical DefenseAberdeen Proving GroundMD
| | - Douglas M. Cerasoli
- Medical Toxicology DivisionUnited States Army Medical Research Institute of Chemical DefenseAberdeen Proving GroundMD
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9
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DeBus S, Dunn EN, Matson EM, Morgan KS, McDonough JH, Cerasoli DM, Cadieux CL. Characterization of Genetically Modified Mice as Improved Animal Models for Organophosphorus Nerve Agent Research. FASEB J 2018. [DOI: 10.1096/fasebj.2018.32.1_supplement.lb67] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Sandra DeBus
- United States Army Medical Research Institute of Chemical DefenseAberdeen Proving GroundMD
| | - Emily N. Dunn
- United States Army Medical Research Institute of Chemical DefenseAberdeen Proving GroundMD
| | - Erik M. Matson
- United States Army Medical Research Institute of Chemical DefenseAberdeen Proving GroundMD
| | - Keith S.L. Morgan
- United States Army Medical Research Institute of Chemical DefenseAberdeen Proving GroundMD
| | - John H. McDonough
- United States Army Medical Research Institute of Chemical DefenseAberdeen Proving GroundMD
| | - Douglas M. Cerasoli
- United States Army Medical Research Institute of Chemical DefenseAberdeen Proving GroundMD
| | - C. Linn Cadieux
- United States Army Medical Research Institute of Chemical DefenseAberdeen Proving GroundMD
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10
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Corbin JM, Kailemia MJ, Cadieux CL, Alkanaimsh S, Karuppanan K, Rodriguez RL, Lebrilla CB, Cerasoli DM, McDonald KA, Nandi S. Purification, characterization, and N-glycosylation of recombinant butyrylcholinesterase from transgenic rice cell suspension cultures. Biotechnol Bioeng 2018; 115:1301-1310. [PMID: 29411865 DOI: 10.1002/bit.26557] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 01/07/2018] [Accepted: 01/29/2018] [Indexed: 11/05/2022]
Abstract
Recombinant butyrylcholinesterase produced in a metabolically regulated transgenic rice cell culture (rrBChE) was purified to produce a highly pure (95%), active form of enzyme. The developed downstream process uses common manufacturing friendly operations including tangential flow filtration, anion-exchange chromatography, and affinity chromatography to obtain a process recovery of 42% active rrBChE. The purified rrBChE was then characterized to confirm its comparability to the native human form of the molecule (hBChE). The recombinant and native enzyme demonstrated comparable enzymatic behavior and had an identical amino acid sequence. However, rrBChE differs in that it contains plant-type complex N-glycans, including an α-1,3 linked core fucose, and a β-1,2 xylose, and lacking a terminal sialic acid. Despite this difference, rrBChE is demonstrated to be an effective stoichiometric bioscavenger for five different organophosphorous nerve agents in vitro. Together, the efficient downstream processing scheme and functionality of rrBChE confirm its promise as a cost-effective alternative to hBChE for prophylactic and therapeutic use.
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Affiliation(s)
- Jasmine M Corbin
- Department of Chemical Engineering, University of California, Davis, California
| | | | - C Linn Cadieux
- Medical Toxicology Division, US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland
| | - Salem Alkanaimsh
- Department of Chemical Engineering, University of California, Davis, California.,Department of Chemical Engineering, College of Engineering and Petroleum, Kuwait University, Safat, Kuwait
| | | | - Raymond L Rodriguez
- Department of Molecular and Cellular Biology, University of California, Davis, California.,Global HealthShare Initiative, University of California, Davis, California
| | | | - Douglas M Cerasoli
- Medical Toxicology Division, US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland
| | - Karen A McDonald
- Department of Chemical Engineering, University of California, Davis, California.,Global HealthShare Initiative, University of California, Davis, California
| | - Somen Nandi
- Department of Chemical Engineering, University of California, Davis, California.,Global HealthShare Initiative, University of California, Davis, California
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11
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Cadieux CL, Wang H, Zhang Y, Koenig JA, Shih TM, McDonough J, Koh J, Cerasoli D. Probing the activity of a non-oxime reactivator for acetylcholinesterase inhibited by organophosphorus nerve agents. Chem Biol Interact 2016; 259:133-141. [PMID: 27062893 DOI: 10.1016/j.cbi.2016.04.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2016] [Revised: 03/23/2016] [Accepted: 04/04/2016] [Indexed: 11/16/2022]
Abstract
Currently fielded treatments for nerve agent intoxication include atropine, an acetylcholine receptor antagonist, and pralidoxime (2PAM), a small molecule reactivator of acetylcholinesterase (AChE). 2PAM reactivates nerve agent-inhibited AChE via direct nucleophilic attack by the oxime moiety on the phosphorus center of the bound nerve agent. Due to a permanently charged pyridinium motif, 2PAM is not thought to cross the blood brain barrier and therefore cannot act directly in the neuronal junctions of the brain. In this study, ADOC, a non-permanently charged, non-oxime molecule initially identified using pesticide-inhibited AChE, was characterized in vitro against nerve agent-inhibited recombinant human AChE. The inhibitory and reactivation potentials of ADOC were determined with native AChE and AChE inhibited with tabun, sarin, soman, cyclosarin, VX, or VR and then compared to those of 2PAM. Several structural analogs of ADOC were used to probe the reactivation mechanism of the molecule. Finally, guinea pigs were used to examine the protective efficacy of the compound after exposure to sarin. The results of both in vitro and in vivo testing will be useful in the design of future small molecule reactivators.
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Affiliation(s)
- C Linn Cadieux
- Research Division, United States Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, MD 21010, USA.
| | - Haoyu Wang
- Chemistry and Biochemistry Department, University of Delaware, Newark, DE 19716, USA
| | - Yuchen Zhang
- Chemistry and Biochemistry Department, University of Delaware, Newark, DE 19716, USA
| | - Jeffrey A Koenig
- Research Division, United States Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, MD 21010, USA
| | - Tsung-Ming Shih
- Research Division, United States Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, MD 21010, USA
| | - John McDonough
- Research Division, United States Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, MD 21010, USA
| | - John Koh
- Chemistry and Biochemistry Department, University of Delaware, Newark, DE 19716, USA
| | - Douglas Cerasoli
- Research Division, United States Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, MD 21010, USA
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12
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Cadieux CL, Wang H, Zhang Y, Koenig J, Shih T, McDonough J, Koh J, Cerasoli D. Phosphonylated Acetylcholinesterase: Probing the Mechanism of a Small Molecule Reactivator. FASEB J 2015. [DOI: 10.1096/fasebj.29.1_supplement.721.7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- C Linn Cadieux
- Research Division United States Army Medical Research Institute of Chemical DefenseAberdeen Proving GroundMarylandUnited States
| | - Haoyu Wang
- Chemistry and Biochemistry DepartmentUniversity of DelawareNewarkDelawareUnited States
| | - Yuchen Zhang
- Chemistry and Biochemistry DepartmentUniversity of DelawareNewarkDelawareUnited States
| | - Jeffrey Koenig
- Research Division United States Army Medical Research Institute of Chemical DefenseAberdeen Proving GroundMarylandUnited States
| | - Tsung‐Ming Shih
- Research Division United States Army Medical Research Institute of Chemical DefenseAberdeen Proving GroundMarylandUnited States
| | - John McDonough
- Research Division United States Army Medical Research Institute of Chemical DefenseAberdeen Proving GroundMarylandUnited States
| | - John Koh
- Chemistry and Biochemistry DepartmentUniversity of DelawareNewarkDelawareUnited States
| | - Douglas Cerasoli
- Research Division United States Army Medical Research Institute of Chemical DefenseAberdeen Proving GroundMarylandUnited States
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13
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Hemmert AC, Otto TC, Chica RA, Wierdl M, Edwards JS, Lewis SL, Edwards CC, Tsurkan L, Cadieux CL, Kasten SA, Cashman JR, Mayo SL, Potter PM, Cerasoli DM, Redinbo MR. Nerve agent hydrolysis activity designed into a human drug metabolism enzyme. PLoS One 2011; 6:e17441. [PMID: 21445272 PMCID: PMC3060870 DOI: 10.1371/journal.pone.0017441] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2010] [Accepted: 02/02/2011] [Indexed: 12/04/2022] Open
Abstract
Organophosphorus (OP) nerve agents are potent suicide inhibitors of the essential neurotransmitter-regulating enzyme acetylcholinesterase. Due to their acute toxicity, there is significant interest in developing effective countermeasures to OP poisoning. Here we impart nerve agent hydrolysis activity into the human drug metabolism enzyme carboxylesterase 1. Using crystal structures of the target enzyme in complex with nerve agent as a guide, a pair of histidine and glutamic acid residues were designed proximal to the enzyme's native catalytic triad. The resultant variant protein demonstrated significantly increased rates of reactivation following exposure to sarin, soman, and cyclosarin. Importantly, the addition of these residues did not alter the high affinity binding of nerve agents to this protein. Thus, using two amino acid substitutions, a novel enzyme was created that efficiently converted a group of hemisubstrates, compounds that can start but not complete a reaction cycle, into bona fide substrates. Such approaches may lead to novel countermeasures for nerve agent poisoning.
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Affiliation(s)
- Andrew C. Hemmert
- Department of Biochemistry/Biophysics and Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Tamara C. Otto
- United States Army Medical Research Institute for Chemical Defense, Aberdeen Proving Ground, Maryland, United States of America
| | - Roberto A. Chica
- Department of Biology and Chemistry, California Institute of Technology, Pasadena, California, United States of America
| | - Monika Wierdl
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Jonathan S. Edwards
- Department of Biochemistry/Biophysics and Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Steven L. Lewis
- Department of Biochemistry/Biophysics and Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Carol C. Edwards
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Lyudmila Tsurkan
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - C. Linn Cadieux
- United States Army Medical Research Institute for Chemical Defense, Aberdeen Proving Ground, Maryland, United States of America
| | - Shane A. Kasten
- United States Army Medical Research Institute for Chemical Defense, Aberdeen Proving Ground, Maryland, United States of America
| | - John R. Cashman
- Human BioMolecular Research Institute, San Diego, California, United States of America
| | - Stephen L. Mayo
- Department of Biology and Chemistry, California Institute of Technology, Pasadena, California, United States of America
| | - Philip M. Potter
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America
| | - Douglas M. Cerasoli
- United States Army Medical Research Institute for Chemical Defense, Aberdeen Proving Ground, Maryland, United States of America
| | - Matthew R. Redinbo
- Department of Biochemistry/Biophysics and Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- * E-mail:
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14
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Geyer BC, Kannan L, Garnaud PE, Broomfield CA, Cadieux CL, Cherni I, Hodgins SM, Kasten SA, Kelley K, Kilbourne J, Oliver ZP, Otto TC, Puffenberger I, Reeves TE, Robbins N, Woods RR, Soreq H, Lenz DE, Cerasoli DM, Mor TS. Plant-derived human butyrylcholinesterase, but not an organophosphorous-compound hydrolyzing variant thereof, protects rodents against nerve agents. Proc Natl Acad Sci U S A 2010; 107:20251-6. [PMID: 21059932 PMCID: PMC2996644 DOI: 10.1073/pnas.1009021107] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The concept of using cholinesterase bioscavengers for prophylaxis against organophosphorous nerve agents and pesticides has progressed from the bench to clinical trial. However, the supply of the native human proteins is either limited (e.g., plasma-derived butyrylcholinesterase and erythrocytic acetylcholinesterase) or nonexisting (synaptic acetylcholinesterase). Here we identify a unique form of recombinant human butyrylcholinesterase that mimics the native enzyme assembly into tetramers; this form provides extended effective pharmacokinetics that is significantly enhanced by polyethylene glycol conjugation. We further demonstrate that this enzyme (but not a G117H/E197Q organophosphorus acid anhydride hydrolase catalytic variant) can prevent morbidity and mortality associated with organophosphorous nerve agent and pesticide exposure of animal subjects of two model species.
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Affiliation(s)
- Brian C. Geyer
- School of Life Sciences and Biodesign Institute, P.O. Box 874501, Arizona State University, Tempe, AZ 85287-4501
| | - Latha Kannan
- School of Life Sciences and Biodesign Institute, P.O. Box 874501, Arizona State University, Tempe, AZ 85287-4501
| | - Pierre-Emmanuel Garnaud
- School of Life Sciences and Biodesign Institute, P.O. Box 874501, Arizona State University, Tempe, AZ 85287-4501
| | - Clarence A. Broomfield
- Research Division, Army Medical Research Institute of Chemical Defense, 3100 Ricketts Point Road, Aberdeen Proving Ground, MD 21010-5400; and
| | - C. Linn Cadieux
- Research Division, Army Medical Research Institute of Chemical Defense, 3100 Ricketts Point Road, Aberdeen Proving Ground, MD 21010-5400; and
| | - Irene Cherni
- School of Life Sciences and Biodesign Institute, P.O. Box 874501, Arizona State University, Tempe, AZ 85287-4501
| | - Sean M. Hodgins
- Research Division, Army Medical Research Institute of Chemical Defense, 3100 Ricketts Point Road, Aberdeen Proving Ground, MD 21010-5400; and
| | - Shane A. Kasten
- Research Division, Army Medical Research Institute of Chemical Defense, 3100 Ricketts Point Road, Aberdeen Proving Ground, MD 21010-5400; and
| | - Karli Kelley
- School of Life Sciences and Biodesign Institute, P.O. Box 874501, Arizona State University, Tempe, AZ 85287-4501
| | - Jacquelyn Kilbourne
- School of Life Sciences and Biodesign Institute, P.O. Box 874501, Arizona State University, Tempe, AZ 85287-4501
| | - Zeke P. Oliver
- Research Division, Army Medical Research Institute of Chemical Defense, 3100 Ricketts Point Road, Aberdeen Proving Ground, MD 21010-5400; and
| | - Tamara C. Otto
- Research Division, Army Medical Research Institute of Chemical Defense, 3100 Ricketts Point Road, Aberdeen Proving Ground, MD 21010-5400; and
| | - Ian Puffenberger
- School of Life Sciences and Biodesign Institute, P.O. Box 874501, Arizona State University, Tempe, AZ 85287-4501
| | - Tony E. Reeves
- Research Division, Army Medical Research Institute of Chemical Defense, 3100 Ricketts Point Road, Aberdeen Proving Ground, MD 21010-5400; and
| | - Neil Robbins
- School of Life Sciences and Biodesign Institute, P.O. Box 874501, Arizona State University, Tempe, AZ 85287-4501
| | - Ryan R. Woods
- School of Life Sciences and Biodesign Institute, P.O. Box 874501, Arizona State University, Tempe, AZ 85287-4501
| | - Hermona Soreq
- Silberman Life Sciences Institute, Edmond J. Safra Campus, Givat Ram, Hebrew University of Jerusalem, Jerusalem, Israel 91904
| | - David E. Lenz
- Research Division, Army Medical Research Institute of Chemical Defense, 3100 Ricketts Point Road, Aberdeen Proving Ground, MD 21010-5400; and
| | - Douglas M. Cerasoli
- Research Division, Army Medical Research Institute of Chemical Defense, 3100 Ricketts Point Road, Aberdeen Proving Ground, MD 21010-5400; and
| | - Tsafrir S. Mor
- School of Life Sciences and Biodesign Institute, P.O. Box 874501, Arizona State University, Tempe, AZ 85287-4501
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15
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Tsai PC, Bigley A, Li Y, Ghanem E, Cadieux CL, Kasten SA, Reeves TE, Cerasoli DM, Raushel FM. Stereoselective hydrolysis of organophosphate nerve agents by the bacterial phosphotriesterase. Biochemistry 2010; 49:7978-87. [PMID: 20701311 DOI: 10.1021/bi101056m] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Organophosphorus compounds include many synthetic, neurotoxic substances that are commonly used as insecticides. The toxicity of these compounds is due to their ability to inhibit the enzyme acetylcholine esterase. Some of the most toxic organophosphates have been adapted for use as chemical warfare agents; the most well-known are GA, GB, GD, GF, VX, and VR. All of these compounds contain a chiral phosphorus center, with the S(P) enantiomers being significantly more toxic than the R(P) enantiomers. Phosphotriesterase (PTE) is an enzyme capable of detoxifying these agents, but the stereochemical preference of the wild-type enzyme is for the R(P) enantiomers. A series of enantiomerically pure chiral nerve agent analogues containing the relevant phosphoryl centers found in GB, GD, GF, VX, and VR has been developed. Wild-type and mutant forms of PTE have been tested for their ability to hydrolyze this series of compounds. Mutant forms of PTE with significantly enhanced, as well as relaxed or reversed, stereoselectivity have been identified. A number of variants exhibited dramatically improved kinetic constants for the catalytic hydrolysis of the more toxic S(P) enantiomers. Improvements of up to 3 orders of magnitude relative to the value of the wild-type enzyme were observed. Some of these mutants were tested against racemic mixtures of GB and GD. The kinetic constants obtained with the chiral nerve agent analogues accurately predict the improved activity and stereoselectivity against the authentic nerve agents used in this study.
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Affiliation(s)
- Ping-Chuan Tsai
- Department of Chemistry, P.O. Box 30012, Texas A&M University, College Station, Texas 77842, USA
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16
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Bruno JG, Carrillo MP, Cadieux CL, Lenz DE, Cerasoli DM, Phillips T. DNA aptamers developed against a soman derivative cross-react with the methylphosphonic acid core but not with flanking hydrophobic groups. J Mol Recognit 2009; 22:197-204. [PMID: 19051203 DOI: 10.1002/jmr.932] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Twelve rounds of systematic evolution of ligands by exponential enrichment (SELEX) were conducted against a magnetic bead conjugate of the para-aminophenylpinacolylmethylphosphonate (PAPMP) derivative of the organophosphorus (OP) nerve agent soman (GD). The goal was to develop DNA aptamers that could scavenge GD in vivo, thereby reducing or eliminating the toxic effects of this dangerous compound. Aptamers were sequenced and screened in peroxidase-based colorimetric plate assays after rounds 8 and 12 of SELEX. The aptamer candidate sequences exhibiting the highest affinity for the GD derivative from round 8 also reappeared in several clones from round 12. Each of the highest affinity PAPMP-binding aptamers also bound methylphosphonic acid (MPA). In addition, the aptamer with the highest overall affinity for PAPMP carried a sequence motif (TTTAGT) thought to bind MPA based on previously published data (J. Fluoresc 18: 867-876, 2008). This sequence motif was found in several other relatively high affinity PAPMP aptamer candidates as well. In studies with the nerve agent GD, pre-incubation of a large molar excess of aptamer candidates failed to protect human butyrylcholinesterase (BuChE) from inhibition. With the aid of three-dimensional molecular modeling of the GD derivative it appears that a hydrophilic cleft sandwiched between the pinacolyl group and the p-aminophenyl ring might channel nucleotide interactions to the phosphonate portion of the immobilized GD derivative. However, bona fide GD free in solution may be repulsed by the negative phosphate backbone of aptamers and rotate its phosphonate and fluorine moieties away from the aptamer to avoid being bound. Future attempts to develop aptamers to GD might benefit from immobilizing the pinacolyl group of bona fide GD to enhance exposure of the phosphonate and fluorine to the random DNA library.
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Affiliation(s)
- John G Bruno
- Operational Technologies Corporation, 4100 NW Loop 410, Suite 230, San Antonio, TX 78229-4253, USA.
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17
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Abstract
Dif and Frz, two Myxococcus xanthus chemosensory pathways, are required in phosphatidylethanolamine (PE) chemotaxis for excitation and adaptation respectively. DifA and FrzCD, the homologues of methyl-accepting chemoreceptors in the two pathways, were examined for methylation in the context of chemotaxis and inter-pathway interactions. Evidence indicates that DifA may not undergo methylation, but signals transmitting through DifA do modulate FrzCD methylation. Results also revealed that M. xanthus possesses Dif-dependent and Dif-independent PE-sensing mechanisms. Previous studies showed that FrzCD methylation is decreased by negative chemostimuli but increased by attractants such as PE. Results here demonstrate that the Dif-dependent sensory mechanism suppresses the increase in FrzCD methylation in attractant response and elevates FrzCD methylation upon negative stimulation. In other words, FrzCD methylation is governed by opposing forces from Dif-dependent and Dif-independent sensing mechanisms. We propose that the Dif-independent but Frz-dependent PE sensing leads to increases in FrzCD methylation and subsequent adaptation, while the Dif-dependent PE signalling suppresses or diminishes the increase in FrzCD methylation to decelerate or delay adaptation. We contend that these antagonistic interactions are crucial for effective chemotaxis in this gliding bacterium to ensure that adaptation does not occur too quickly relative to the slow speed of M. xanthus movement.
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Affiliation(s)
- Qian Xu
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061-0910, USA
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18
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Cadieux CL, Guzman JJ, Corun CM, Rausa RC, Lenz DE, Cerasoli DM. Comparing the susceptibility of genetically modified mice to intoxication by organophosphorus nerve agents. FASEB J 2008. [DOI: 10.1096/fasebj.22.1_supplement.717.8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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