title: Species-specific and structure-dependent debromination of polybrominated diphenyl ether in fish by in vitro hepatic metabolism.
abstract: To explore the cause of species-specific differences and structure-activity relationships in the debromination of polybrominated diphenyl ethers (PBDEs) in fish, a series of in vitro measurements of hepatic metabolism of PBDE were made using crucian carp (Carassius carassius) and catfish (Silurus asotus) and the activity of deiodinase in liver microsomes was measured. Debromination was observed in the crucian carp but not in the catfish. No difference was found in total deiodinase activity despite the activity of type 1 deiodinase in crucian carp being twice that of catfish. It is difficult to determine whether the differences in deiodinase activity were responsible for the species-specific differences observed. In crucian carp, penta-brominated diphenyl ether congeners exhibited the highest debromination rates, and the transformation rate decreased with an increasing number of substituted bromines. Adjacent bromine substitution in the phenyl ring was a necessary, but insufficient, condition for debromination in crucian carp. Doubly flanked bromine was always preferentially removed, while single-flanked bromine, meta-substituted bromine, was debrominated the most, followed by para- and then ortho-bromine. No debromination was observed for single-flanked bromine when there was a symmetrical structure with (2, 4, 6) bromine substitutions in 1 phenyl ring, indicating that this structure can improve resistance to debromination metabolism. Environ Toxicol Chem 2017;36:2005-2011. © 2017 SETAC.
authors.affiliation: State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Resources Utilization and Protection, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, People's Republic of China.|University of Chinese Academy of Sciences, Beijing, People's Republic of China.
authors.forename: Yuan-Lai
authors.initials: YL
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Resources Utilization and Protection, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, People's Republic of China.
authors.forename: Xiao-Jun
authors.initials: XJ
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Resources Utilization and Protection, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, People's Republic of China.|University of Chinese Academy of Sciences, Beijing, People's Republic of China.
authors.forename: Mei-Xia
authors.initials: MX
authors.lastname: Ye
authors.affiliation: State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Resources Utilization and Protection, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, People's Republic of China.
authors.forename: Yan-Hong
authors.initials: YH
authors.lastname: Zeng
authors.affiliation: State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Resources Utilization and Protection, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, People's Republic of China.
authors.forename: She-Jun
authors.initials: SJ
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Resources Utilization and Protection, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, People's Republic of China.
authors.forename: Bi-Xian
authors.initials: BX
authors.lastname: Mai
mesh_terms: D000818:Animals; D002347:Carps / Q000378:metabolism*; D002397:Catfishes / Q000378:metabolism*; D055768:Halogenated Diphenyl Ethers / Q000737:chemistry / Q000378:metabolism*; D066298:In Vitro Techniques; D007453:Iodide Peroxidase / Q000378:metabolism; D008862:Microsomes, Liver / Q000378:metabolism*; D011075:Polybrominated Biphenyls / Q000737:chemistry / Q000378:metabolism*; D013045:Species Specificity; D013329:Structure-Activity Relationship; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000378:metabolism*
chemical_list: D055768:Halogenated Diphenyl Ethers; D011075:Polybrominated Biphenyls; D014874:Water Pollutants, Chemical; C109812:iodothyronine deiodinase type I; D007453:Iodide Peroxidase
keywords: Debromination; Deiodinase; Fish liver microsome; Polybrominated diphenyl ether; Structure