P-450-Dependent oxidative rearrangement in isoflavone biosynthesis: Reconstitution of P-450 and NADPH:P-450 reductase

✍ Scribed by Takashi Hakamatsuka; Muhammed Faisal Hashim; Yutaka Ebizuka; Ushio Sankawa

• Book ID: 104204024
• Publisher: Elsevier Science
• Year: 1991
• Tongue: French
• Weight: 704 KB
• Volume: 47
• Category: Article
• ISSN: 0040-4020
• DOI: 10.1016/s0040-4020(01)86489-9

✦ Synopsis

The reaction mechanism of oxidative rearrangement in the conversion of liquiritigenin, a flavanone, into 2,7.4'-trihydroxyisoflavanone was studied in elicitor-challenged Pueraria fobata cell cultures. The involvement of cytochrome P-450 in the reaction, hydroxylation associated with 1,2-aryl migration, was proved previously by the inhibition experiments with carbon monoxide and P-450 inhibitors. In order to obtain rigorous evidence proving that the enzyme is a P-450, a reconstitution experiment was performed with solubilixed cytochrome P-450 and NADPH:cytochrome P-450 reductase fractions. During these studies we noticed that various biosynthetic reactions can be interpreted as P-450-mediated reactions associated with migration or bond cleavage. Ring contraction of 'I-hydroxy-kaurenoic acid in gibberellin biosynthesis, the formation of a furan ring in furanocoumarin biosynthesis and several rearrangement reactions in steroid metabolism are discussed as examples of P-450 reactions associated with migration or bond cleavage.