Cytochrome P-450-Dependent Hydroxylation of Lauric Acid at the Subterminal Position and Oxidation of Unsaturated Analogs in Wheat Microsomes

摘要: Microsomes from etiolated wheat (Triticum aestivum L. cv Etoile de Choisy) shoots catalyzed the reduced nicotinamide adenine dinucleotide phosphate-dependent hydroxylation of lauric acid predominantly at subterminal or (ω-1) position (65%). Minor amounts 10-hydroxy- (31%) and 9-hydroxylaurate (4%) were also formed. The reaction was by cytochrome P-450, since enzyme activity strongly inhibited tetcyclacis, carbon monoxide, antibodies against NADPH-cytochrome c (P-450)-reductase. apparent Km for estimated to be 8.5 ± 2.0 μm. Seed treatment with safener naphthalic anhydride seedlings phenobarbital increased P-450 content hydroxylase (LAH) microsomes. A combination both treatments further stimulated LAH activity. series radiolabeled unsaturated analogs (8-, 9-, 10-, 11-dodecenoic acids) used explore regioselectivity catalytic capabilities induced It has been found that microsomes epoxidation sp2 carbons concurrently saturated positions. oxidation substrates similar. Preincubation phosphate resulted in a partial loss