Oxidation microsomal mixed-function

Estabrook, R.W., Hildebrandt, A.G., Baron, J., Netter, K.J. and Leibman, K. (1971) A new spectral intermediate associated with cytochrome P-450 function in liver microsomes. Biochemical and Biophysical Research Communications, 42 (1), 132-139. Pompon, D. and Coon, M.J. (1984) On the mechanism of action of cytochrome P-450. Oxidation and reduction of the ferrous dioxygen complex of liver microsomal cytochrome P-450 by cytochrome b5. Journal of Biological Chemistry, 259 (24), 15377-15385. Hildebrandt, A. and Estabrook, R.W. (1971) Evidence for the participation of cytochrome b 5 in hepatic microsomal mixed-function oxidation reactions. Archives of Biochemistry and Biophysics, 143 (1), 66-79. 

Microsomal Mixed-Function Oxidation in Untreated and Polycyclic Aromatic Hydrocarbon-Treated Marine Fish... 

Bend, J.R., Ball, L.M., Elmamlouk, T.H., James, M.O. and Philpot, R.M. Microsomal mixed-function oxidation in untreated and polycyclic aromatic hydrocarbon-treated marine fish. This volume. 

The predicted stoichiometry in microsomal mixed function oxidations for NADPH substrate oxygen is 1 1 1 325), In the absence of substrate NADPH oxidase is measured and in the presence of substrate this background oxidase activity is present though oxygen consumption increases 326, 326). As the level of substrate increases the expected stoichiometry is approached 326, 328). The addition of potential substrates which cannot be hydroxylated, such as perfluoro-n-hexane, leads to increased oxygen consumption and this has been termed uncoupling 327). It has been demonstrated that some of the electrons lost from the system are... 

Species differences with regard to various toxic effects based on such chemical lesions and their localization in particular tissues are understandable on basis of species and tissue differences in the capacity of metabolizing pharmaca. The pharmacon under these circumstances acts as a toxogen (compare pharmacogen). It may be emphasized that, although the microsomal mixed-function oxidative system in the liver cells is generally considered to be a de-... 

Hildebrandt, A. and R.W. Estabrook (1971). Evidence for the participation of cytochrome b5 in hepatic microsomal mixed-function oxidation reactions. Arch. Biochem. Biophys. 143, 66-79. 

Lipid-soluble xenobiotics are commonly biotra ns formed by oxidation in the drug-metabolizing microsomal system (DMMS). For each description below, choose the component of the microsomal mixed-function oxidase system with which it is most closely associated ... 

In addition, oral administration of 1- C-2-hexanone to humans or rats results in the appearance of CO in the expired breath (DiVincenzo et al. 1977, 1978), indicating oxidation/cleavage of the alpha carbon. Administration of SKF525A (a mixed function oxidase inhibitor) to rats before oral administration of 2-hexanone resulted in a marked decrease in the excretion of respiratory CO for the first 4 hours after administration, followed by a marked increase at 4-8 and 12-24 hours. This suggests that this oxidative step is mediated by a microsomal mixed function oxidase system (DiVincenzo etal. 1977). 

In addition to alcohol dehydrogenase, ethanol can be oxidized to acetaldehyde by the microsomal mixed-function oxidase system (cytochrome P450 2 El), as illustrated in Figure 35.1. Although this microsomal ethanol-oxidizing system probably has minor impor-... 

Hasson, E.P., West, C.A. "Properties of the system for the mixed function oxidation of kaurene and kaurene derivatives in microsomes of the immature seed of Mar ah macrocarpus. Cofactor requirements." Plant Physiol., 1976, 58 473- 78. 

The microsomal mixed-function oxidase enzyme system further oxidizes the diol to the carcinogenic 7,8-diol-9,10-epoxide ... 

Tredger, J.M., et al. Postnatal development of mixed-function oxidation as measured in microsomes from the small intestine and liver of rabbits. Drug Metab Dispos, 1976 4 17-23... 

Microsomes contain, in addition to the two cytochrome reductases just discussed, a flavoprotein which catalyzes the mixed function oxidation of secondary and tertiary amines to the hydroxylamines and amine oxides, respectively (333, 334). This flavoprotein, which contains about 2 moles of phospholipid and 1 mole of FAD per 70,000 g of protein, is specific for NADPH (333, 334) The enzyme is also able to catalyze the further oxidation of the hydroxylamines to nitrones (336). The reactions... 

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