title: Biodegradation of 3-methyldiphenylether (MDE) by Hydrogenophaga atypical strain QY7-2 and cloning of the methy-oxidation gene mdeABCD.
abstract: 3-Methyldiphenylether (MDE) is an important alkyl-substituted diphenyl ether compound that is widely used as an intermediate in the synthesis of pyrethroid insecticides. An efficient MDE-degrading strain QY7-2, identified as Hydrogenophaga atypical, was isolated from activated sludge for the first time. Strain QY7-2 can utilize MDE as the sole carbon and energy source and completely mineralize MDE. The degradation pathway of MDE was proposed in the strain through metabolites identification. A gene cluster involving in methy-oxidation of MDE was cloned from QY7-2 and expressed in Escherichia coli BL21 (DE3), and the products were purified by SDS-PAGE. The specific activities of the recombinant enzymes MdeAB, MdeC and MdeD were 113.8 ± 3.5, 274.5 ± 6.2 and 673.4 ± 8.7 nmol min-1mg-1, respectively. These results provide the biochemical and genetic foundation of microbial degradation pathway of MDE and benefit the bioremediation of MDE-contaminated environments.
authors.affiliation: The College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Yang
authors.affiliation: Jiangsu Academy of Agriculture Science, Nanjing 210014, People's Republic of China.
authors.forename: Shu
authors.initials: S
authors.lastname: Cai
authors.affiliation: The College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors.forename: Shaowei
authors.initials: S
authors.lastname: Dong
authors.affiliation: The College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors.forename: Lulu
authors.initials: L
authors.lastname: Chen
authors.affiliation: The College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors.forename: Jifei
authors.initials: J
authors.lastname: Chen
authors.affiliation: The College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors.forename: Tianming
authors.initials: T
authors.lastname: Cai
mesh_terms: D000074061:ATP Binding Cassette Transporter, Subfamily D / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001673:Biodegradation, Environmental; D002851:Chromatography, High Pressure Liquid; D003001:Cloning, Molecular; D042621:Comamonadaceae / Q000378:metabolism*; D004926:Escherichia coli / Q000378:metabolism; D004986:Ether / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D007700:Kinetics; D016296:Mutagenesis; D053719:Tandem Mass Spectrometry
chemical_list: D000074061:ATP Binding Cassette Transporter, Subfamily D; D001426:Bacterial Proteins; D004986:Ether