NADPH oxidase cytosolic factors

Lomax, K. J., Leto, T. L., Nunoi, H., Gallin, J. I., Malech, H. L. (1989). Recombinant 47-kilodalton cytosol factor restores NADPH oxidase in chronic granulomatous disease. Science 245, 409-12. 

In 1991 inhibition of PKC activity was found to be at the basis of the vascular smooth muscle cell growth arrest induced by a-tocopherol [16,17]. A number of reports have subsequently confirmed the involvement of PKC in the effect of a-tocopherol on different cell types, including monocytes, macrophages, neutrophils, fibroblasts and mesangial cells [8,18-20]. a-Tocopherol, but not P-tocopherol, was found to inhibit thrombin-induced PKC activation and endothelin secretion in endothelial cells [21]. a-Tocopherol, and not P-tocopherol or trolox, inhibits the activity of PKC fi-om monocytes, followed by inhibition of phosphorylation and translocation of the cytosolic factor p47(phox) and by an impaired assembly of the NADPH-oxidase and of superoxide production [22]. a-Tocopherol has the important biological effect of inhibiting the release of the proinflammatory cytokine, IL-lp, via inhibition of the 5-lipoxygenase pathway [23]. 

Four different mutations cause CGD and these cause four defects in different components of the NADPH oxidase. These are the two membrane bound components of cytochrome bssg and two cytosolic factors p4 P ° and pgyphox jggj fgj. jj2g f-Qjjj. proteins have been mapped in... 

The A6 desaturase is a membrane bound enzyme (Catala et al, 1975) that is inhibited by cyanide (Brenner and Peluffo, 1969). It is considered a mixed function oxidase. Both NADH and NADPH are electron donors and cytochrome b5 reductase and cytochrome b5 transport the electrons to the enzyme. Two hydrogens of the reduced cofactors and two hydrogens of the fatty acids are combined to oxygen to form 2 molecules of water. Acyl-CoAs are substrates for the enzyme. The full activity of the enzyme b ound to the microsome is reached when a cytosolic factor of proteical structure is present (Brenner, 1974 Catala et al, 1975 Nervi et al, 1975). 

Pilloud-Dagher, M., Jouan, A., and Vignais, P. V., 1992, Purification and properties of a functional 47-kilodalton cytosolic factor required for NADPH-oxidase activation in bovine neutrophils, Biochem. Biophys. Res. Commun. 186 731-738. 

Chloroethanes have been shown to undergo dechlorination by an enzyme system that is similar to the hepatic microsomal mixed function oxidase system (Van Dyke and Wineman 1971). Dechlorination was inducible by phenobarbital and required oxygen and NADPH. However, dechlorination also required a factor from the cytosolic fraction of the liver homogenate for optimal dechlorinating activity. In terms of structural requirements, dechlorination was enhanced if the carbon atom containing the chlorine had only one hydrogen. In a microsomal incubation, 13.5% of... 

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