Cross-Linking of Cytochrome P-450: Effect of Temperature
The monooxygenase system of the endoplasmic reticulum of liver cells is of great importance to the production of reactive metabolites from xenobiotics, and in recent years there has been a good deal of interest in attempting to discover the molecular organization of this enzyme system in the membrane (Peterson et al., 1976, 1978; Yang, 1975, 1977). The system comprises two protein components: (i) cytochrome P-450 reductase and (ii) cytochrome P-450. The function of cytochrome P-450 reductase is to bring about the transfer of electrons from NADPH to the terminal oxidase of the system, cytochrome P-450, which binds both the xenobiotic substrate and molecular oxygen. Unlike the reductase, cytochrome P-450 exists in a number of distinct forms, each of which demonstrates different characteristics with respect to substrate preference and catalytic parameters.
KeywordsFluorescence Polarization Microsomal Membrane Rabbit Liver Molecular Aggregate Monooxygenase System
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