title: Microbial degradation of fomesafen by a newly isolated strain Pseudomonas zeshuii BY-1 and the biochemical degradation pathway.
abstract: Fomesafen is a diphenyl ether herbicide used to control the growth of broadleaf weeds in bean fields. Although the degradation of fomesafen in soils was thought to occur primarily by microbial activity, little was known about the kinetic and metabolic behaviors of this herbicide. This paper reported the capability of the newly isolated strain Pseudomonas zeshuii BY-1 to use fomesafen as the sole source of carbon in pure culture for its growth. Up to 88.7% of 50 mg of L(-1) fomesafen was degraded by this bacterium in mineral medium within 3 days. Strain BY-1 could also degrade other diphenyl ethers, including lactofen, acifluorfen, and fluoroglycofen. During the fomesafen degradation, five metabolites were detected and identified by liquid chromatography-mass spectrometry and tandem mass spectrometry. The primary degradation pathway of fomesafen might be the reduction of the nitro group to an amino group, followed by the acetylation of the amino derivative, dechlorination, and cleavage of the S-N bond. The addition of the BY-1 stain into soils treated with fomesafen resulted in a higher degradation rate than that observed in uninoculated soils, and the bacteria community in contaminated soil recovered after inoculation of the BY-1 stain. On the basis of these results, strain P. zeshuii BY-1 has the potential to be used in the bioremediation of fomesafen-contaminated soils.
authors: Department of Microbiology, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu 210095, People's Republic of China.
authors: Zhao-zhong
authors: ZZ
authors: Feng
authors: Qin-fen
authors: QF
authors: Li
authors: Jun
authors: J
authors: Zhang
authors: Jing
authors: J
authors: Zhang
authors: Xing
authors: X
authors: Huang
authors: Peng
authors: P
authors: Lu
authors: Shun-peng
authors: SP
authors: Li
mesh_terms: D001549:Benzamides / Q000378:metabolism*; D001673:Biodegradation, Environmental; D004269:DNA, Bacterial / Q000032:analysis; D006540:Herbicides / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D011549:Pseudomonas / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D012987:Soil / Q000032:analysis; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000378:metabolism
chemical_list: D001549:Benzamides; D004269:DNA, Bacterial; D006540:Herbicides; D012987:Soil; D012989:Soil Pollutants; C088563:fomesafen