title: Butyrylcholinesterase identification in a phenylvalerate esterase-enriched fraction sensitive to low mipafox concentrations in chicken brain.
abstract: Multiple epidemiological and experimental studies have demonstrated that exposure to organophosphorus compounds (OPs) is associated with a variety of neurological disorders. Some of these exposure symptoms cannot be precisely correlated with known molecular targets and mechanisms of toxicity. Most of the known molecular targets of OPs fall in the protein family of serine esterases. We have shown that three esterase components in the soluble fraction of chicken brain (an animal model frequently used in OP neurotoxicity assays) can be kinetically distinguished using paraoxon, mipafox and phenylmethyl sulfonyl fluoride as inhibitors, and phenyl valerate as a substrate; we termed them Eα, Eβ and Eγ. The Eα-component, which is highly sensitive to paraoxon and mipafox and resistant to PMSF, has shown sensitivity to the substrate acetylthiocholine, and to ethopropazine and iso-OMPA (specific inhibitors of butyrylcholinesterase; BChE) but not to BW 284C51 (a specific inhibitor of acetylcholinesterase; AChE). In this work, we employed a large-scale proteomic analysis B with a LC/MS/MS TripleTOF system; 259 proteins were identified in a chromatographic fractionated sample enriched in Eα activity of the chicken brain soluble fraction. Bioinformatics analysis revealed that BChE is the only candidate protein identified to be responsible for almost all the Eα activity. This study demonstrates the potential information to be gained from combining kinetic dissection with large-scale proteomics and bioinformatics analyses for identification of proteins that are targets of OP toxicity and may be involved in detoxification of phosphoryl and carbonyl esters.
authors.affiliation: Institute of Bioengineering, University "Miguel Hernandez" of Elche, Alicante, Spain. imangas@umh.es.|Department of Pharmacology, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California-San Diego, La Jolla, CA, 92093-0650, USA. imangas@umh.es.|Laboratory of Molecular Modeling Applied to the Chemical and Biological Defense (CAPES 88887.065877/2014-00), Military Institute of Engineering, Urca, Rio de Janeiro, Brazil. imangas@umh.es.
authors.forename: Iris
authors.initials: I
authors.lastname: Mangas
authors.affiliation: Department of Pharmacology, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California-San Diego, La Jolla, CA, 92093-0650, USA.
authors.forename: Zoran
authors.initials: Z
authors.lastname: Radić
authors.affiliation: Department of Pharmacology, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California-San Diego, La Jolla, CA, 92093-0650, USA.
authors.forename: Palmer
authors.initials: P
authors.lastname: Taylor
authors.affiliation: Department of Chemistry and Biochemistry, Natural Sciences Building, University of California-San Diego, La Jolla, CA, 92093-0378, USA.
authors.forename: Majid
authors.initials: M
authors.lastname: Ghassemian
authors.affiliation: Institute of Bioengineering, University "Miguel Hernandez" of Elche, Alicante, Spain.
authors.forename: Héctor
authors.initials: H
authors.lastname: Candela
authors.affiliation: Institute of Bioengineering, University "Miguel Hernandez" of Elche, Alicante, Spain.
authors.forename: Eugenio
authors.initials: E
authors.lastname: Vilanova
authors.affiliation: Institute of Bioengineering, University "Miguel Hernandez" of Elche, Alicante, Spain.
authors.forename: Jorge
authors.initials: J
authors.lastname: Estévez
mesh_terms: D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D002091:Butyrylcholinesterase / Q000378:metabolism*; D002265:Carboxylic Ester Hydrolases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D002645:Chickens; D002853:Chromatography, Liquid / Q000379:methods; D019295:Computational Biology / Q000379:methods; D004305:Dose-Response Relationship, Drug; D007531:Isoflurophate / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000633:toxicity; D010640:Phenothiazines / Q000494:pharmacology; D040901:Proteomics / Q000379:methods; D053719:Tandem Mass Spectrometry / Q000379:methods
chemical_list: D010640:Phenothiazines; D007531:Isoflurophate; C005238:mipafox; C084820:profenamine; D002265:Carboxylic Ester Hydrolases; C021859:neurotoxic esterase; D002091:Butyrylcholinesterase
keywords: Brain; Butyrylcholinesterase; LC-MSMS; Neuropathy Target Esterase; Organophosphorus compounds; Phenyl valerate esterases