Metabolism of the herbicides chlorotoluron, diuron, linuron, simazine, and atrazine by CYP1A9 and CYP1C1 from Japanese eel (Anguilla japonica)

Abstract Through the use of a number of bioconversion experiments we demonstrated that P450 proteins (CYP1A9 and CYP1C1) from Japanese eel ( Anguilla japonica ) metabolized a number of herbicides and the drug phenacetin. We performed bioconversion experiments in which substrates were added directly to incubation medium. The resulting metabolites were extracted and analyzed by high-performance liquid chromatography. Proteins CYP1A9 and CYP1C1 metabolized 50 nmol of the drug phenacetin to yield 12.1 and 1.1 nmol of product (acetaminophen), respectively. Further incubation of CYP1A9 with 50 nmol of the herbicides chlorotoluron, diuron, linuron, simazine, or atrazine yielded 16.5, 18.5, 7.3, 1.6, or 0.8 nmol of product, respectively. CYP1C1 also metabolized linuron, diuron, and simazine yield 5.4, 4.6, or 0.7 nmol of product, respectively. Next, polyclonal antibody was isolated by immunizing with two conjugated-peptides (amino acid residues 272–290 and 294–310) of CYP1A9. This antibody did not recognize human CYP1A2 or CYP1C1. Western blotting using the antibody revealed one band in the livers of Japanese eel and tilapia ( Oreochromis niloticus ). Theses results suggest that CYP1A9 and CYP1C1 metabolize herbicides, and that CYP1A9 is an useful biomarker of contamination when detected with this antibody.