title: Purification and characterization of a novel pyrethroid hydrolase from Aspergillus niger ZD11.
abstract: The pyrethroid pesticides residues on foods and environmental contamination are a public safety concern. Pretreatment with pyrethroid hydrolase has the potential to alleviate the conditions. For this purpose, a fungus capable of using pyrethroid pesticides as a sole carbon source was isolated from the soil and characterized as Aspergillus niger ZD11. A novel pyrethroid hydrolase from cell extract was purified 41.5-fold to apparent homogeneity with 12.6% overall recovery. It is a monomeric structure with a molecular mass of 56 kDa, a pI of 5.4, and the enzyme activity was optimal at 45 degrees C and pH 6.5. The activities were strongly inhibited by Hg(2+), Ag(+), and rho-chloromercuribenzoate, whereas less pronounced effects (5-10% inhibition) were observed in the presence of the remaining divalent cations, the chelating agent EDTA and phenanthroline. The purified enzyme hydrolyzed various insecticides with similar carboxylester. trans-Permethrin is the preferred substrate.
authors.affiliation: State Key Laboratory of Biocontrol, School of Life Science, Zhongshan University, Guangzhou, People's Republic of China.
authors.forename: Wei Q
authors.initials: WQ
authors.lastname: Liang
authors.forename: Zhuo Y
authors.initials: ZY
authors.lastname: Wang
authors.forename: He
authors.initials: H
authors.lastname: Li
authors.forename: Pei C
authors.initials: PC
authors.lastname: Wu
authors.forename: Ji M
authors.initials: JM
authors.lastname: Hu
authors.forename: Na
authors.initials: N
authors.lastname: Luo
authors.forename: Li X
authors.initials: LX
authors.lastname: Cao
authors.forename: Yu H
authors.initials: YH
authors.lastname: Liu
mesh_terms: D001234:Aspergillus niger / Q000201:enzymology*; D004795:Enzyme Stability; D006863:Hydrogen-Ion Concentration; D006867:Hydrolases / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D008970:Molecular Weight; D011722:Pyrethrins / Q000378:metabolism*; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D011722:Pyrethrins; D006867:Hydrolases