Oxidoreductases;
Acting on paired donors, with incorporation or reduction of molecular oxygen;
With oxidation of a pair of donors resulting in the reduction of O2 to two molecules of water
The enzyme, characterized from the green alga Chlamydomonas reinhardtii, is a front-end desaturase that introduces a cis double bond in omega9 unsaturated C18 or C20 fatty acids incorporated into lipids, at a position 4 carbon atoms from the existing omega9 bond, towards the carboxy end of the fatty acid (at the omega13 position). When acting on 20:2Delta(11,14) and 20:3Delta(11,14,17) substrates it introduces the new double bond between carbons 7 and 8. The enzyme contains a cytochrome b5 domain that acts as the direct electron donor for the active site of the desaturase.
Kajikawa M, Yamato KT, Kohzu Y, Shoji S, Matsui K, Tanaka Y, Sakai Y, Fukuzawa H
Title
A front-end desaturase from Chlamydomonas reinhardtii produces pinolenic and coniferonic acids by omega13 desaturation in methylotrophic yeast and tobacco.
