Epoxygenase

Smith WL, Fitzpatrick FA The eicosanoids Cyclooxygenase, lipoxygenase, and epoxygenase pathways. In Biochemistry of Lipids, Lipoproteins and Membranes. Vance DE, Vance JE (editors). Elsevier, 1996. 

In plant tissues, various enzymes convert the hydroperoxides produced by LOX to other products, some of which are important as flavor compounds. These enzymes include hydroperoxide lyase, which catalyzes the formation of aldehydes and oxo acids hydroperoxide-dependent peroxygenase and epoxygenase, which catalyze the formation of epoxy and hydroxy fatty acids, and hydroperoxide isomerase, which catalyzes the formation of epoxyhydroxy fatty acids and trihydroxy fatty acids. LOX produces flavor volatiles similar to those produced during autoxidation, although the relative proportions of the products may vary widely, depending on the specificity of the enzyme and the reaction conditions. 

Eicosanoid synthesis. Arachidonic acid is converted by cyclooxygenases into prostaglandins, and thromboxanes. Lipoxygenases convert arachidonic acid into HPETEs, which are then converted to lipoxins, leukotrienes, and 12-HETE (hydroxyeicosatetraenoic acid). Epoxygenases convert arachidonic acid into epoxides. 

Alkayed NJ, Narayanan J, Gebremedhin D, Medhora M, Roman RJ, et al. 1996. Molecular characterization of an arachidonic acid epoxygenase in rat brain astrocytes. Stroke... 

Amruthesh SC, Falck JR, EUis EE. 1992. Brain synthesis and cerebrovascular action of epoxygenase metabolites of arachidonic acid. J Neurochem 58 503-510. 

Wu S, Moomaw CR, Tomer KB, Falck JR, Zeldin DC. 1996. Molecular cloning and expression of CYP2J2, a human cytochrome P450 arachidonic acid epoxygenase highly expressed in heart. J Biol Chem 271 3460-3468. 

Zeldin DC, Moomaw CR, Jesse N, Tomer KB, Beetham J, et al. 1996. Biochemical characterization of the human liver cytochrome P450 arachidonic acid epoxygenase pathway. Arch Biochem Biophys 330 87-96. 

Figure 9.5. CYP epoxygenase- and hydroxylase-mediated metabolism of arachidonic acid. Products include biologically active EETs and HETEs. (Adapted from Seubert et al. Prostaglandins and Other Lipid Mediators 82, 50-59, 2007.)...

Zeldin, D. C. Epoxygenase pathways of arachidonic acid metabolism. /. Biol. Chem. 276, 36059-36062, 2001. 

Chen JK, Capdevila J, Harris RC. Cytochrome p450 epoxygenase 118. metabolism of arachidonic acid inhibits apoptosis. Mol. Cell Biol. 2001 21 6322-6331. 

VanRollins M. (1995). Epoxygenase metabolites of docosahexaenoic and eicosi >elItaenoic acids inhibit platelet aggregation at concentrations below those affecting thromboxane synthesis. J. Pharmacol. Ejqytl. TherapeuL 274,798-804. 

Generation of aldehydes is discussed to be achieved by action of lyases and hydroperoxidases [198,217,218] epoxygenases are claimed to transfer IffODEs to epoxy hydroxy fatty acids [217,219] which are... 

Many of the biological actions of essential fatty acids are the result of their metabolic products, the eicosanoids. These are oxidized derivatives of AA and include prostaglandins and thromboxanes that are formed via the cyclo-oxygenase (COX) pathway, as well as hydroxy fatty acids and leukotrienes that arise by means of the lipoxygenase pathway. Another series of AA-derived products, the epoxy fatty acids, are produced by the cytochrome P450 epoxygenase pathway. The AA that serves as precursor for these reactions... 

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