Purification of lipoxygenase and hydroperoxide dehydrase in flaxseeds: Interaction between these enzymatic activities

We have purified two enzymic activities from flaxseed acetone powder : a lipoxygenase and a hydroperoxide dehydrase. The lipoxygenase activity belongs to an iron-containing protein having a molecular weight of 130 kDa which, upon incubation with α-linolenic acid, forms 13-hydroperoxy-9(Z), 11 (E), 15(Z)- octadecatrienoic acid. The hydroperoxide dehydrase (a 55 kDa protein) metabolizes this hydroperoxide to an allene oxide which in turn is spontaneously hydrolyzed to α-and γ-ketols. Relationships between these two enzymes were studied and results suggest an inhibition of the lipoxygenase by hydroperoxide dehydrase.