This view shows enzymes only for those organisms listed below, in the list of taxa known to possess the pathway. If an enzyme name is shown in bold, there is experimental evidence for this enzymatic activity.
Synonyms: vernolic acid biosynthesis
|Superclasses:||Biosynthesis → Fatty Acids and Lipids Biosynthesis → Fatty Acid Biosynthesis → Unusual Fatty Acid Biosynthesis|
Expected Taxonomic Range: Viridiplantae
Vernolic acid is an unusual fatty acid containing an epoxy bond. It was found in high concentration in seed oils of the Vernonia sp, Crepis palaestina as well as Euphorbia lagascae (from 60 up to 75%). Epoxy fatty acids are widely used as plastisizers.
Divergent classes of enzymes have been reported to catalyze the synthesis of vernolic acid from linoleic acid. In developing seeds of Euphorbia lagascae, the epoxidation reaction can be catalyzed by a cytochrome P450 which acts on linoleic acid bound to phosphatidylcholine [Bafor93] as well as on free linoleic acids [Blee93]. A peroxygenase was also reported in this plant to epoxidize free linoleic acid to vernolic acid [Blee93]. In contrast, in Crepis palaestina, a fatty acid desaturase-like enzyme is involved [Lee98a].
Bafor93: Bafor M, Smith MA, Jonsson L, Stobart K, Stymne S (1993). "Biosynthesis of vernoleate (cis-12-epoxyoctadeca-cis-9-enoate) in microsomal preparations from developing endosperm of Euphorbia lagascae." Arch Biochem Biophys 303(1);145-51. PMID: 8489257
Blee93: Blee E, Stahl U, Schuber F, Stymne S (1993). "Regio- and stereoselectivity of cytochrome P-450 and peroxygenase-dependent formation of cis-12,13-epoxy-9(Z)-octadecenoic acid (vernolic acid) in Euphorbia lagascae." Biochem Biophys Res Commun 197(2);778-84. PMID: 8267615
Lee98a: Lee M, Lenman M, Banas A, Bafor M, Singh S, Schweizer M, Nilsson R, Liljenberg C, Dahlqvist A, Gummeson PO, Sjodahl S, Green A, Stymne S (1998). "Identification of non-heme diiron proteins that catalyze triple bond and epoxy group formation." Science 280(5365);915-8. PMID: 9572738
Cahoon02: Cahoon EB, Ripp KG, Hall SE, McGonigle B (2002). "Transgenic production of epoxy fatty acids by expression of a cytochrome P450 enzyme from Euphorbia lagascae seed." Plant Physiol 128(2);615-24. PMID: 11842164
Sauveplane09: Sauveplane V, Kandel S, Kastner PE, Ehlting J, Compagnon V, Werck-Reichhart D, Pinot F (2009). "Arabidopsis thaliana CYP77A4 is the first cytochrome P450 able to catalyze the epoxidation of free fatty acids in plants." FEBS J 276(3);719-35. PMID: 19120447
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