Reaction: a 1-linoleoyl-2-acyl-[glycerolipid] + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+ = a 1-γ-linolenoyl-2-acyl-[glycerolipid] + 2 oxidized ferredoxin [iron-sulfur] cluster + 2 H2O
Other name(s): desD (gene name)
Systematic name: 1-linoleoyl-2-acyl-[glycerolipid],ferredoxin:oxygen oxidoreductase (6,7-cis-dehydrogenating)
Comments: The enzyme, characterized from cyanobacteria, introduces a cis double bond at carbon 6 of linoleoyl groups (18:2) attached to the sn-1 position of glycerolipids. The enzyme is a front-end desaturase, introducing the new double bond between a pre-existing double bond and the carboxyl-end of the fatty acid. It is nonspecific with respect to the polar head group of the glycerolipid.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Higashi, S. and Murata, N. An in vivo study of substrate specificities of acyl-lipid desaturases and acyltransferases in lipid synthesis in Synechocystis PCC6803. Plant Physiol. 102 (1993) 1275-1278. [PMID: 12231903]
2. Reddy, A.S. and Thomas, T.L. Expression of a cyanobacterial Δ6-desaturase gene results in γ-linolenic acid production in transgenic plants. Nat. Biotechnol. 14 (1996) 639-642. [PMID: 9630958]
3. Kurdrid, P., Subudhi, S., Hongsthong, A., Ruengjitchatchawalya, M. and Tanticharoen, M. Functional expression of Spirulina-Δ6 desaturase gene in yeast, Saccharomyces cerevisiae. Mol. Biol. Rep. 32 (2005) 215-226. [PMID: 16328883]