ExplorEnz: EC 1.14.19.31

Your query returned 1 entry. Printable version

1.14.19.31

Accepted name:

acyl-lipid (7-3)-desaturase

Reaction:

(1) a (7Z,10Z,13Z,16Z,19Z)-docosa-7,10,13,16,19-pentaenoyl-[glycerolipid] + 2 ferrocytochrome b₅ + O₂ + 2 H⁺ = a (4Z,7Z,10Z,13Z,16Z,19Z)-docosa-4,7,10,13,16,19-hexaenoyl-[glycerolipid] + 2 ferricytochrome b₅ + 2 H₂O
(2) a (7Z,10Z,13Z,16Z)-docosa-7,10,13,16-tetraenoyl-[glycerolipid] + 2 ferrocytochrome b₅ + O₂ + 2 H⁺ = a (4Z,7Z,10Z,13Z,16Z)-docosa-4,7,10,13,16-pentaenoyl-[glycerolipid] + 2 ferricytochrome b₅ + 2 H₂O

Glossary:

(7Z,10Z,13Z,16Z)-docosa-7,10,13,16-tetraenoate = adrenate

Other name(s):

D4Des (gene name); des1 (gene name); CrΔ⁴FAD (gene name); acyl-lipid 4-desaturase

Systematic name:

Δ⁷ acyl-lipid,ferrocytochrome b₅:oxygen oxidoreductase (4,5 cis-dehydrogenating)

Comments:

The enzymes from several algae introduce a cis double bond at the 4-position in 22-carbon polyunsaturated fatty acids that contain a Δ⁷ double bond. The enzyme from the fresh water alga Chlamydomonas reinhardtii acts on the 16 carbon fatty acid (7Z,10Z,13Z)-hexadeca-7,10,13-trienoate [5]. The enzyme contains an N-terminal cytochrome b₅ domain that acts as the direct electron donor to the active site of the desaturase, and does not require an external cytochrome.

Links to other databases:

BRENDA, EXPASY, KEGG, MetaCyc

References:

1.	Qiu, X., Hong, H. and MacKenzie, S.L. Identification of a Δ⁴ fatty acid desaturase from Thraustochytrium sp. involved in the biosynthesis of docosahexanoic acid by heterologous expression in Saccharomyces cerevisiae and Brassica juncea. J. Biol. Chem. 276 (2001) 31561–31566. [DOI] [PMID: 11397798]
2.	Tonon, T., Harvey, D., Larson, T.R. and Graham, I.A. Identification of a very long chain polyunsaturated fatty acid Δ⁴-desaturase from the microalga Pavlova lutheri. FEBS Lett. 553 (2003) 440–444. [DOI] [PMID: 14572666]
3.	Meyer, A., Cirpus, P., Ott, C., Schlecker, R., Zähringer, U. and Heinz, E. Biosynthesis of docosahexaenoic acid in Euglena gracilis: biochemical and molecular evidence for the involvement of a Δ⁴-fatty acyl group desaturase. Biochemistry 42 (2003) 9779–9788. [DOI] [PMID: 12911321]
4.	Zhou, X.R., Robert, S.S., Petrie, J.R., Frampton, D.M., Mansour, M.P., Blackburn, S.I., Nichols, P.D., Green, A.G. and Singh, S.P. Isolation and characterization of genes from the marine microalga Pavlova salina encoding three front-end desaturases involved in docosahexaenoic acid biosynthesis. Phytochemistry 68 (2007) 785–796. [DOI] [PMID: 17291553]
5.	Zäuner, S., Jochum, W., Bigorowski, T. and Benning, C. A cytochrome b₅-containing plastid-located fatty acid desaturase from Chlamydomonas reinhardtii. Eukaryot Cell 11 (2012) 856–863. [DOI] [PMID: 22562471]

[EC 1.14.19.31 created 2015]