Self-inactivation by 13-hydroperoxylinoleic acid and lipohydroperoxidase activity of the reticulocyte lipoxygenase.
1. The self-inactivation of lipoxygenase from rabbit reticulocytes with linoleic acid at 37 degrees C is caused by the product 13-hydroperoxylinoleic acid. This inactivation is promoted by either oxygen or linoleic acid. 2. Lipohydroperoxidase activity was demonstrated with 13-hydroperoxylinoleic acid plus linoleic acid as hydrogen donor under anaerobic conditions at 2 degrees C. The products were 13-hydroxylinoleic acid, oxodienes and compounds of non-diene structure similar to those produced by soybean lipoxygenase-1. 3. 13-Hydroperoxylinoleic acid also changed the absorbance and fluorescence properties of reticulocyte lipoxygenase. The results indicate that one equivalent of 13-hydroperoxylinoleic acid converts the enzyme from the ferrous state into the ferric state as described for soybean lipoxygenase-1. The spectral changes were reversed by sodium borohydride at 2 degrees C, but not at 37 degrees C; it is assumed that the ferric form of reticulocyte lipoxygenase suffers inactivation.
D000818:Animals; D055598:Chemical Phenomena; D002621:Chemistry; D019787:Linoleic Acid; D008041:Linoleic Acids / Q000096:biosynthesis* / Q000494:pharmacology*; D016859:Lipoxygenase Inhibitors; D011817:Rabbits; D012156:Reticulocytes / Q000201:enzymology*; D013025:Glycine max
D008041:Linoleic Acids; D016859:Lipoxygenase Inhibitors; D019787:Linoleic Acid; C032890:13-hydroperoxylinoleic acid