| Synonyms |
16:2/18:2 desaturase, acyl-lipid omega-3 desaturase, FAD7, FAD7 omega 3-desaturase, FAD7-1, FAD7-2, FAD8, fatty acid desaturase 7, fatty acid desaturase-7, fatty acid desaturase7, GmFAD7, HaFAD7, HvFAD7, omega-3 desaturase, omega-3 FA desaturase, omega-3 fatty acid desaturase, omega-3 fatty acid desaturase gene, omega3 fatty acid desaturase, omega3-fatty acid desaturase, OsFAD8, PfrFAD7-1, PfrFAD7-2, plastid omega-3 desaturase, plastidial FAD7 omega-3 desaturase, plastidial omega-3 desaturase, plastidial omega-3 fatty acid desaturase, Sefad7, sn-2 acyl-lipid omega-3 desaturase (ferredoxin) |
| Comments |
This plastidial enzyme desaturates 16:2 fatty acids attached to the sn-2 position of glycerolipids to 16:3 fatty acids, and converts18:2 to 18:3 in both the sn-1 and sn-2 positions. It acts on all 16:2- or 18:2-containing chloroplast membrane lipids, including phosphatidylglycerol, monogalactosyldiacylglycerol, digalactosyldiaclyglycerol, and sulfoquinovosyldiacylglycerol. The enzyme introduces a cis double bond at a location 3 carbons away from the methyl end of the fatty acid. The distance from the carboxylic acid end of the molecule does not affect the location of the new double bond. cf. EC 1.14.19.25, acyl-lipid ¦Ø-3 desaturase (cytochrome b5) and EC 1.14.19.36, sn-1 acyl-lipid ¦Ø-3 desaturase (ferredoxin). |
| Reactions |
(1) A (7Z,10Z)-hexadeca-7,10-dienoyl-[glycerolipid] + 2 reduced ferredoxin [iron-sulfur] cluster + O(2) + 2 H(+) = a (7Z,10Z,13Z)- hexadeca-7,10,13-trienoyl-[glycerolipid] + 2 oxidized ferredoxin [iron- sulfur] cluster + 2 H(2)O. (2) A linoleoyl-[glycerolipid] + 2 reduced ferredoxin [iron-sulfur] cluster + O(2) + 2 H(+) = an alpha-linolenoyl-[glycerolipid] + 2 oxidized ferredoxin [iron-sulfur] cluster + 2 H(2)O. |
