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Published on: March 28, 2017
Spectrophotometric analysis of human CYP2E1-catalyzed p-nitrophenol hydroxylation
Thomas K H Chang1, Charles L Crespi, David J Waxman
1Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, Canada.
Abstract:
The cytochrome P450 enzyme CYP2E1 catalyzes the oxidative metabolism of many solvents and other small organic molecules. A spectrophotometric method is described for determination of CYP2E1 activity by monitoring the formation of p-nitrocatechol from p-nitrophenol by cDNA-expressed CYP2E1 or isolated liver microsomes. The enzymatic product, p-nitrocatechol, is assayed at 535 nm after acidification of the reaction mixture with trichloroacetic acid followed by neutralization using 2 M NaOH. This method is applicable to enzymatic studies for determination of P450-catalyzed p-nitrophenol hydroxylation activity.
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