Reaction: (8R,9Z,12Z)-8-hydroperoxyoctadeca-9,12-dienoate = (5S,8R,9Z,12Z)-5,8-dihydroxyoctadeca-9,12-dienoate
Other name(s): 5,8-LDS (bifunctional enzyme); 5,8-linoleate diol synthase (bifunctional enzyme); 8-hydroperoxide isomerase; (8R,9Z,12Z)-8-hydroperoxy-9,12-octadecadienoate mutase ((5S,8R,9Z,12Z)-5,8-dihydroxy-9,12-octadecadienoate-forming); PpoA
Systematic name: (8R,9Z,12Z)-8-hydroperoxyoctadeca-9,12-dienoate hydroxymutase [(5S,8R,9Z,12Z)-5,8-dihydroxyoctadeca-9,12-dienoate-forming]
Comments: The enzyme contains heme [3]. 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 (cf. EC 1.13.11.60, linoleate 8R-lipoxygenase), which is subsequently isomerized to (5S,8R,9Z,12Z)-5,8-dihydroxyoctadeca-9,12-dienoate within the C-terminal P-450 heme thiolate domain [3].
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:
References:
1. Hoffmann, I., Jerneren, F., Garscha, U. and Oliw, E.H. Expression of 5,8-LDS of Aspergillus fumigatus and its dioxygenase domain. A comparison with 7,8-LDS, 10-dioxygenase, and cyclooxygenase. Arch. Biochem. Biophys. 506 (2011) 216-222. [PMID: 21130068]
2. Jerneren, F., Garscha, U., Hoffmann, I., Hamberg, M. and Oliw, E.H. Reaction mechanism of 5,8-linoleate diol synthase, 10R-dioxygenase, and 8,11-hydroperoxide isomerase of Aspergillus clavatus. Biochim. Biophys. Acta 1801 (2010) 503-507. [PMID: 20045744]
3. Brodhun, F., Gobel, C., Hornung, E. and 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 (2009) 11792-11805. [PMID: 19286665]