title: Identification of the biochemical degradation pathway of triazophos and its intermediate in Diaphorobacter sp. TPD-1.
abstract: Triazophos is one of the most widely used organophosphorus insecticides usually detectable in the environment. A bacterial strain, Diaphorobacter sp. TPD-1, capable of using triazophos and its intermediate, 1-phenyl-3-hydroxy-1,2,4-triazole (PHT), as its sole carbon sources for growth was isolated from a triazophos-contaminated soil in China. This strain could completely degrade 50 mg l(-1) triazophos and PHT to non-detectable level in 24 and 56 h, respectively. During PHT degradation, three metabolites were detected and identified based on tandem mass spectrometry (MS/MS) analysis. Using this information, a biochemical degradation pathway of triazophos by Diaphorobacter sp. TPD-1 was proposed. The first step involved in the degradation of triazophos is the hydrolysis of the P-O ester bond of triazophos to form PHT and o,o-diethyl phosphorothioic acid, then the triazol ring of PHT is subsequently cleaved to form (E)-1-formyl-2-phenyldiazene. Subsequently, (E)-1-formyl-2-phenyldiazene is transformed to 2-phenylhydrazinecarboxylic acid by adding one molecular of H(2)O. Finally, the carboxyl group of 2-phenylhydrazinecarboxylic acid is decarboxylated to form phenylhydrazine.
authors.affiliation: Department of Microbiology, Key Laboratory for Microbiological Engineering of Agricultural Environment of Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors.forename: Chengli
authors.initials: C
authors.lastname: Yang
authors.forename: Rong
authors.initials: R
authors.lastname: Li
authors.forename: Yao
authors.initials: Y
authors.lastname: Song
authors.forename: Kai
authors.initials: K
authors.lastname: Chen
authors.forename: Shunpeng
authors.initials: S
authors.lastname: Li
authors.forename: Jiandong
authors.initials: J
authors.lastname: Jiang
mesh_terms: D001673:Biodegradation, Environmental; D002681:China; D042621:Comamonadaceae / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D006868:Hydrolysis; D007306:Insecticides / Q000737:chemistry / Q000378:metabolism*; D015394:Molecular Structure; D063086:Organothiophosphates / Q000737:chemistry / Q000378:metabolism*; D012988:Soil Microbiology; D014230:Triazoles / Q000737:chemistry / Q000378:metabolism*
chemical_list: D007306:Insecticides; D063086:Organothiophosphates; D014230:Triazoles; C012584:triazophos