Oxidoreductases;
Acting on single donors with incorporation of molecular oxygen (oxygenases);
With incorporation of two atoms of oxygen

linoleate:oxygen (8R)-oxidoreductase

linoleate + O2 = (8R,9Z,12Z)-8-hydroperoxyoctadeca-9,12-dienoate [RN:R07061]

R07061

linoleate [CPD:C01595];
O2 [CPD:C00007]

The enzyme contains heme [1,4]. The bifunctional enzyme from Aspergillus nidulans uses different heme domains to catalyse two separate reactions. Linoleic acid is oxidized within the N-terminal heme peroxidase domain to (8R,9Z,12Z)-8-hydroperoxyoctadeca-9,12-dienoate, which is subsequently isomerized by the C-terminal P-450 heme thiolate domain to (5S,8R,9Z,12Z)-5,8-dihydroxyoctadeca-9,12-dienoate (cf. EC 5.4.4.5, 9,12-octadecadienoate 8-hydroperoxide 8R-isomerase) [1]. The bifunctional enzyme from Gaeumannomyces graminis also catalyses the oxidation of linoleic acid to (8R,9Z,12Z)-8-hydroperoxyoctadeca-9,12-dienoate, but its second domain isomerizes it to (7S,8S,9Z,12Z)-5,8-dihydroxyoctadeca-9,12-dienoate (cf. EC 5.4.4.6, 9,12-octadecadienoate 8-hydroperoxide 8S-isomerase) [4].

EC 1.13.11.60 created 2011

1  [PMID:19286665]

Brodhun F, Gobel C, Hornung E, Feussner I

Identification of PpoA from Aspergillus nidulans as a fusion protein of a fatty acid heme dioxygenase/peroxidase and a cytochrome P450.

J Biol Chem 284:11792-805 (2009)
DOI:10.1074/jbc.M809152200

[ani:AN1967.2]

2  [PMID:8117115]

Hamberg M, Zhang LY, Brodowsky ID, Oliw EH.

Sequential oxygenation of linoleic acid in the fungus Gaeumannomyces graminis: stereochemistry of dioxygenase and hydroperoxide isomerase reactions.

Arch Biochem Biophys 309:77-80 (1994)
DOI:10.1006/abbi.1994.1087

3  [PMID:18586008]

Garscha U, Oliw E

Pichia expression and mutagenesis of 7,8-linoleate diol synthase change the dioxygenase and hydroperoxide isomerase.

Biochem Biophys Res Commun 373:579-83 (2008)
DOI:10.1016/j.bbrc.2008.06.060

4  [PMID:8662736]

Su C, Oliw EH.

Purification and characterization of linoleate 8-dioxygenase from the fungus Gaeumannomyces graminis as a novel hemoprotein.

J Biol Chem 271:14112-8 (1996)
DOI:10.1074/jbc.271.24.14112

[ag:AAD49559]