Cytochrome P450-dependent monooxygenase

Since endosulfan is a cytochrome P450-dependent monooxygenase inducer, the quantification of specific enzyme activities (e.g., aminopyrine-A -demethylase, aniline hydroxylase) may indicate that exposure to endosulfan has occurred (Agarwal et al. 1978). Because numerous chemicals and drugs found at hazardous waste sites and elsewhere also induce hepatic enzymes, these measurements are nonspecific and are not necessarily an indicator solely of endosulfan exposure. However, these enzyme levels can be useful indicators of exposure, together with the detection of endosulfan isomers or the sulfate metabolite in the tissues or excreta. 

Exposure. Known biomarkers of exposure to endosulfan include the measurement of endosulfan or its metabolites in tissue and excreta (Deema et al. 1966 Dorough et al. 1978 Gorbach et al. 1968) these measurements can indicate whether absorption of endosulfan has occurred. The presence of the parent compound and its metabolites are specific biomarkers for endosulfan exposure. However, no studies are available that quantify the concentrations of endosulfan or its metabolites in relation to specific environmental exposure levels. Since endosulfan induces cytochrome P450-dependent monooxygenases... 

Boon, J.P., Van Arnhem, E., and Jansen, S. et al. (1992). The toxicokinetics of PCBs in marine mammals with special reference to possible interactions of individual congeners with cytochrome P450 dependent monooxygenase systems an overview. In C.H Walker and D. Livingstone (1992). Persistent Pollutants in Marine Ecosystems 119-160. 

Dufosse, L. and de Echanove, C., The last step in the biosynthesis of aryl carotenoids in the cheese ripening bacteria Brevibacterium linens ATCC 9175 (Brevibacterium aurantiacum sp. nov.) involves a cytochrome P450-dependent monooxygenase. Food Res. Int, 38, 967, 2005. 

Humphreys, J. M. Hemm, M. R. Chappie, C. Ferulate 5-hydroxylase fromArahidopsis is a multifunctional cytochrome P450-dependent monooxygenase catalyzing parallel hydroxylations in phenylpropanoid metabolism. Proc. Natl. Acad Sci. USA 1999, 96, 10045-10050. 

Chappie, C. (1998) Molecular-genetic analysis of plant cytochrome P450-dependent monooxygenases. Annual Review of Plant Physiology and Plant Molecular Biology, 49, 311-343. 

Fouchecourt, M.O. and J.L. Riviere. 1995. Activities of cytochrome P450-dependent monooxygenases and antioxidant enzymes in different organs of Norway rats (Rattus norvegicus) inhabiting reference and contaminated sites. Chemosphere 3L4375A386. 

In microsomes from Sinapis alba L.,33,34 Tropaeolum majus L.,35,36 and Carica papaya L.,37 the aromatic amino acids (tyrosine and phenylalanine) have been shown to be converted to the corresponding oximes by cytochrome P450-dependent monooxygenases. The conversion of tyrosine to the corresponding oxime in microsomes from S. alba was approximately 1000 fold lower than in microsomes from the cyanogenic sorghum.33 This made a biochemical approach for the isolation... 

Minn AT, Pelczar H, Denizot C, Martinet M, Heydel JM, et al. 2005. Characterization of microsomal cytochrome P450-dependent monooxygenases in the rat olfactory mucosa. Drug Metab Dispos 33 1229-1237. 

Ueng, Y. E., Wang, J. J., Lin, L. C., Park, S. S. and Chen, C. F. 2001. Induction of cytochrome P450-dependent monooxygenase in mouse liver and kidney by rutaecarpine, an alkaloid of the herbal drug Evodia rutaecarpa. Life Sciences, 70 207-217. 

Tetrachloroethane causes central nervous system depression and is highly hepatotoxic in mice and dogs it produced embryotoxic effects and a low incidence of malformations in mice. A single oral dose (437 mg/kg bw) of 1,1,2,2-tetrachloroethane decreased the activity of some hepatic cytochrome P450-dependent monooxygenases and, to a smaller extent, that of UDP-glucuronosyl transferase (lARC, 1979). 

Meyer, K., Shirley, A. M., Cusumano, J. C., Bell-Lelong, D. A., and Chappie, C., 1998, Lignin monomer composition is determined by the expression of a cytochrome P450-dependent monooxygenase in Arabidopsis, Proc. Natl. Acad. Sci. USA 95 6619-6623. 

Lambert GH, Kotake AN, Schoeller D. The C02 breath tests as monitors of the cytochrome P450 dependent mixed function monooxygenase system. Prog Clin Biol Res 1983 135 119-145. 

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