title: Biodegradation of nicosulfuron by the bacterium Serratia marcescens N80.
abstract: By enrichment culturing of the sludge collected from the industrial wastewater treatment pond, we isolated a highly efficient nicosulfuron degrading bacterium Serratia marcescens N80. In liquid medium, Serratia marcescens N80 grows using nicosulfuron as the sole nitrogen source, and the optimal temperature, pH values, and inoculation for degradation are 30-35°C, 6.0-7.0, and 3.0% (v/v), respectively. With the initial concentration of 10 mg L⁻¹, the degradation rate is 93.6% in 96 hours; as the initial concentrations are higher than 10 mg L⁻¹, the biodegradation rates decrease as the nicosulfuron concentrations increase; when the concentration is 400 mg L⁻¹, the degradation rate is only 53.1%. Degradation follows the pesticide degradation kinetic equation at concentrations between 5 mg L⁻¹ and 50 mg L⁻¹. Identification of the metabolites by the liquid chromatography/mass spectrometry (LC/MS) indicates that the degradation of nicosulfuron is achieved by breaking the sulfonylurea bridge. The strain N80 also degraded some other sulfonylurea herbicides, including ethametsulfuron, tribenuron-methyl, metsulfuron-methyl, chlorimuron-ethyl,and rimsulfuron.
authors.affiliation: College of Resource and Environment, Jilin Agricultural University, Changchun, People's Republic of China.
authors.forename: Hao
authors.initials: H
authors.lastname: Zhang
authors.forename: Wenhui
authors.initials: W
authors.lastname: Mu
authors.forename: Zhiguang
authors.initials: Z
authors.lastname: Hou
authors.forename: Xian
authors.initials: X
authors.lastname: Wu
authors.forename: Weiwei
authors.initials: W
authors.lastname: Zhao
authors.forename: Xianghui
authors.initials: X
authors.lastname: Zhang
authors.forename: Hongyu
authors.initials: H
authors.lastname: Pan
authors.forename: Shihong
authors.initials: S
authors.lastname: Zhang
mesh_terms: D001483:Base Sequence; D001673:Biodegradation, Environmental; D002853:Chromatography, Liquid; D004269:DNA, Bacterial; D006540:Herbicides / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D011725:Pyridines / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S; D017422:Sequence Analysis, DNA; D012706:Serratia marcescens / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D012722:Sewage / Q000382:microbiology; D013453:Sulfonylurea Compounds / Q000378:metabolism*; D013696:Temperature
chemical_list: D004269:DNA, Bacterial; D006540:Herbicides; D011725:Pyridines; D012336:RNA, Ribosomal, 16S; D012722:Sewage; D013453:Sulfonylurea Compounds; C416723:nicosulfuron