A novel approach to study the activity and stoichiometry simultaneously for microsomal pentoxyresorufin-O-dealkylase reaction
作者： Shipra Rastogi , Mukul Das , Subhash K Khanna
DOI: 10.1016/S0014-5793(02)02234-2
关键词: Stoichiometry 、 Cytochrome 、 Specific activity 、 Stereochemistry 、 Substrate (chemistry) 、 Microsome 、 Enzyme 、 Chemistry 、 Metabolism 、 Electron donor
摘要: Abstract A simple approach to study the activity and stoichiometry of cytochrome P-450 IIB1-catalyzed metabolism pentoxyresorufin (PRF) has been investigated. It involves continuous spectral analysis reaction mixture containing PRF, microsomes from phenobarbital-induced rats NADPH. The kinetics NADPH consumption, PRF utilization, NADP resorufin formation was monitored at λmax 338, 484, 260 572 nm, respectively. enzyme tabulated either by specific or Vmax value showed that 10 molecules were required for conversion one molecule along with NADP. Further, it observed almost six are consumed in incubation devoid indicating possibility endogenous substrates. Interestingly, ratio 1:1 established even presence inhibitors a lower rate metabolism. However, altered inhibitors, suggesting simultaneous monitoring substrate, electron donor products could be useful understanding modifications substrate/product.
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