title: Isolation and characterization of a pseudomonas oleovorans degrading the chloroacetamide herbicide acetochlor.
abstract: To date, no pure bacterial cultures that could degrade acetochlor have been described. In this study, one strain of microorganism capable of degrading acetochlor, designated as LCa2, was isolated from acetochlor-contaminated soil. The strain LCa2 is Pseudomonas oleovorans according to the criteria of Bergey's manual of determinative bacteriology and sequence analysis of the partial 16S rRNA gene. Optimum growth temperature and pH were 35 degrees C and 8.0, respectively. The strain could degrade 98.03% of acetochlor treated at a concentration of 7.6 mg l(-1) after 7 days of incubation and could tolerate 200 mg l(-1) of acetochlor. When the acetochlor concentration became higher, the degradation cycle became longer. The acetochlor biodegradation products were identified by GC-MS based on mass spectral data and fragmentation patterns. The main plausible degradative pathways involved dechlorination, hydroxylation, N-dealkylation, C-dealkylation and dehydrogenation.
authors.affiliation: Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, 25 Beisihuanxi Lu, Haidian, 100080, Beijing, PR China.
authors.forename: Jun
authors.initials: J
authors.lastname: Xu
authors.forename: Xinghui
authors.initials: X
authors.lastname: Qiu
authors.forename: Jiayin
authors.initials: J
authors.lastname: Dai
authors.forename: Hong
authors.initials: H
authors.lastname: Cao
authors.forename: Min
authors.initials: M
authors.lastname: Yang
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.forename: Muqi
authors.initials: M
authors.lastname: Xu
mesh_terms: D006540:Herbicides / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007218:Industrial Microbiology / Q000379:methods*; D008969:Molecular Sequence Data; D044204:Pseudomonas oleovorans / Q000145:classification / Q000302:isolation & purification / Q000502:physiology*; D012988:Soil Microbiology; D014052:Toluidines / Q000737:chemistry / Q000378:metabolism*
chemical_list: D006540:Herbicides; D014052:Toluidines; C043377:acetochlor