IUBMB Enzyme Nomenclature


Accepted name: 9,12-octadecadienoate 8-hydroperoxide 8S-isomerase

Reaction: (8R,9Z,12Z)-8-hydroperoxyoctadeca-9,12-dienoate = (7S,8S,9Z,12Z)-7,8-dihydroxyoctadeca-9,12-dienoate

Other name(s): 8-hydroperoxide isomerase (ambiguous); (8R,9Z,12Z)-8-hydroperoxy-9,12-octadecadienoate mutase ((7S,8S,9Z,12Z)-5,8-dihydroxy-9,12-octadecadienoate-forming)

Systematic name: (8R,9Z,12Z)-8-hydroperoxyoctadeca-9,12-dienoate hydroxymutase [(7S,8S,9Z,12Z)-7,8-dihydroxyoctadeca-9,12-dienoate-forming]

Comments: The enzyme contains heme. The bifunctional enzyme from Gaeumannomyces graminis catalyses the oxidation of linoleic acid to (8R,9Z,12Z)-8-hydroperoxyoctadeca-9,12-dienoate (cf. EC, linoleate 8R-lipoxygenase), which is then isomerized to (7S,8S,9Z,12Z)-5,8-dihydroxyoctadeca-9,12-dienoate [3].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:


1. Hamberg, M., Zhang, L.-Y., Brodowsky, I.D. and Oliw, E.H. Sequential oxygenation of linoleic acid in the fungus Gaeumannomyces graminis: stereochemistry of dioxygenase and hydroperoxide isomerase reactions. Arch. Biochem. Biophys. 309 (1994) 77-80. [PMID: 8117115]

2. Su, C., Sahlin, M. and Oliw, E.H. A protein radical and ferryl intermediates are generated by linoleate diol synthase, a ferric hemeprotein with dioxygenase and hydroperoxide isomerase activities. J. Biol. Chem. 273 (1998) 20744-20751. [PMID: 9694817]

3. Su, C. and Oliw, E.H. Purification and characterization of linoleate 8-dioxygenase from the fungus Gaeumannomyces graminis as a novel hemoprotein. J. Biol. Chem. 271 (1996) 14112-14118. [PMID: 8662736]

[EC created 2011]

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