Journal: PLoS ONE
Article Title: An Iron 13 S -Lipoxygenase with an α-Linolenic Acid Specific Hydroperoxidase Activity from Fusarium oxysporum
doi: 10.1371/journal.pone.0064919
Figure Lengend Snippet: The reaction starts with stereo specific abstraction of a specific hydrogen either from the C-11 or C-14 of the fatty acid backbone yielding a carbon centered radical that is delocalized via the π-electron system. In case of the predominant 13-LOX activity the pro R -hydrogen is abstracted from the C-11 and oxygen is inserted antarafacially at the C-13 yielding 13 S -HPOT. The product is further converted either by isomerization yielding 12,13-Ep-11-HOD or dehydration forming 13-KOT. In case of 9-LOX activity 9-HPOT is formed by hydrogen insertion at the C-9. Abstraction of the hydrogen at the C-14 leads analogously to the formation of a delocalized carbon centered radical that can be either trapped at the C-12 (12-LOX activity) or at the C-16 (16-LOX activity) yielding 12-H(P)OTE or 16-H(P)OTE, respectively. The latter product might be further converted to 15,16-EpOT by elimination of a hydrogen from the C-11. The epoxy-group of this leukotriene A like metabolite can be attacked by water either at the C-15 (yielding 15,16-DiHOT) or at the C-9 (yielding 9,16-DiHOT).
Article Snippet: The following reference oxylipins were purchased from Lipidox Co. (Stockholm, Sweden) or Larodan (Malmö, Sweden): 13-HOT, 13-KOT, 12 S ,13 S -epoxy-11 R -hydroxy-9 Z ,15 Z -octadecadienoic acid ( threo form), 12 S ,13 S -epoxy-11 S -hydroxy-9 Z ,15 Z -octadecadienoic acid ( erythr o form), erythro - and threo -15,16-dihydroxyoctadecanoic acids, and 9,16-dihydroxyoctadecanoic acid.
Techniques: Activity Assay