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: calendic acid biosynthesis
|Superclasses:||Biosynthesis → Fatty Acids and Lipids Biosynthesis → Fatty Acid Biosynthesis → Unusual Fatty Acid Biosynthesis → Conjugated Fatty Acid Biosynthesis|
Some taxa known to possess this pathway include : Calendula officinalis
Expected Taxonomic Range: Magnoliophyta
Seed oils of a few plant species are enriched in conjugated fatty aids, fatty acids containing conjugated or non-methylene-interrupted double bonds. These conjugated double bonds are introduced by "conjugases", divergent forms of FAD2 (oleic acid desaturase). Conjugases modify an existing double bond to produce the conjugated double bonds with or without introducing a new double bond. They use fatty acids bound to phosphatidylcholine as substrates, as has been shown for FAD2 enzymes. Because conjugated double bonds have high rates of oxidation, seed oils rich in conjugated double bonds are used commercially as drying agents in paints and varnishes.
Calendic acid (18:3Δ8trans,10trans,12cis) is a conjugated form of linolenic acid (18:3Δcis9,cis12,cis15). It is a major fatty acid component of the seed oil of Calendula officinalis, accounting for 50-60% (w/w) of the seed oil. Calendic acid is derived from linoleic acid (18:2Δcis9,cis12) by a fatty acid conjugase which converts a cis Δ9 double bond into a conjugated trans-trans double bond system.
Cahoon01: Cahoon EB, Ripp KG, Hall SE, Kinney AJ (2001). "Formation of conjugated delta8,delta10-double bonds by delta12-oleic-acid desaturase-related enzymes: biosynthetic origin of calendic acid." J Biol Chem 276(4);2637-43. PMID: 11067856
Qiu01: Qiu X, Reed DW, Hong H, MacKenzie SL, Covello PS (2001). "Identification and analysis of a gene from Calendula officinalis encoding a fatty acid conjugase." Plant Physiol 125(2);847-55. PMID: 11161042
Reed02: Reed DW, Savile CK, Qiu X, Buist PH, Covello PS (2002). "Mechanism of 1,4-dehydrogenation catalyzed by a fatty acid (1,4)-desaturase of Calendula officinalis." Eur J Biochem 269(20);5024-9. PMID: 12383261
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