Oxygen-Isotope Effect in Enzymatic Cleavage Reaction of 13-L-Hydroperoxylinoleic Acid to Hexanal and ll-Formyl-c/s-9-undecenoic Acid

Hydroperoxide lyase, 1 l-Formyl-c/5-9-undecenoie Acid, 180-Labeled 13-L-Hydroperoxylinoleic acid, Oxygen-Isotope Effect Hydroperoxide lyase E" solubilized with Tween 20 from tea chloroplasts was shown to catalyze cleavage reaction of 13-L-hydroperoxy-cz'j-9,fra/w-11-octadecadienoic acid (13-L-hydroperoxylinoleic acid) to hexanal, a CB-compound and 1 l-form yl-m -9-undecenoic acid, a C12-compound by identification of cleavage products using authentic specimens synthesized through an unequivocal route. An oxygen-isotope effect was first observed in the cleavage reaction of l80 labeled 13-L-hydroperoxylinoleic acid by solubilized E'2'. The 180-atom of hydroperoxide was not detected in carbonyl group of hexanal formed from 180-labeled 13-L-hydroperoxylinoleic acid.