ID   1.14.19.25
DE   acyl-lipid omega-3 desaturase (cytochrome b5).
CA   a (9Z,12Z)-octadecadienoyl-containing glycerolipid + 2 Fe(II)-[cytochrome
CA   b5] + 2 H(+) + O2 = (9Z,12Z,15Z)-octadecatrienoyl-containing glycerolipid
CA   + 2 Fe(III)-[cytochrome b5] + 2 H2O.
CC   -!- This microsomal enzyme introduces a cis double bond three carbons
CC       away from the methyl end of a fatty acid incorporated into a
CC       glycerolipid.
CC   -!- The distance from the carboxylic acid end of the molecule does not
CC       have an effect.
CC   -!- The plant enzyme acts on carbon 15 of linoleoyl groups incorporated
CC       into both the sn-1 and sn-2 positions of the glycerol backbone of
CC       phosphatidylcholine and other phospholipids, converting them into
CC       alpha-linolenoyl groups.
CC   -!- The enzyme from the fungus Mortierella alpina acts on gamma-
CC       linolenoyl and arachidonoyl groups, converting them into stearidonoyl
CC       and icosapentaenoyl groups, respectively. cf. EC 1.14.19.35.
DR   P48623, FAD3E_ARATH;  P48624, FAD3E_BRANA;  Q59J82, FAD3E_MORAP;
//