Coumarin-Based Profluorescent and Fluorescent Substrates for Determining Xenobiotic-Metabolizing Enzyme Activities In Vitro.

摘要: in vivo methods, such as spectrophotometric, fluorometric, mass spectrometric,and radioactivity-based techniques. In fluorescence-based assays, the reaction produces a fluorescentproduct from nonfluorescent substrate or vice versa. Fluorescence-based enzyme assays areusually highly sensitive and specific, allowing measurements on small specimens of tissues withlow activities. Fluorescence are also amenable to miniaturization reactionmixtures can thus be done high throughput. 7-Hydroxycoumarin its derivatives arewidely used fluorophores due their desirable photophysical properties. They possess large -conjugated system with electron-rich charge transfer This conjugated structure leadsto applications 7-hydroxycoumarins fluorescent sensors for biological We describe inthis review historical highlights current use coumarins evaluatingactivities major types xenobiotic-metabolizing systems. Traditionally, coumarinsubstrates have been measure oxidative activities cytochrome P450 (CYP) enzymes. For thispurpose, profluorescent very sensitive, but generally lack selectivity individual CYPforms. With aid molecular modeling, we recently described several new coumarin-basedsubstrates measuring CYP conjugating enzymes improved selectivity.