ENZYMIC 10-O-HYDROXYLATION AND 10-O-METHYLATION OF DIHYDROSANGUINARINE IN DIHYDROCHELIRUBINE FORMATION BY ESCHSCHLOLTZIA

Article abstract of DOI:10.1016/0031-9422(92)83617-8

Two new enzymes involved in benzophenanthridine alkaloid biosynthesis, dihydrosanguinarine-10-hydroxylase and 10-hydroxydihydrosanguinarine-10-O-methyltransferase, have been found in cell-free extracts derived from Eschscholtzia californica cell suspension culturees.The hydroxylase is a microsome-associated, cytochrome P-450-dependent monooxygenase which acts specifically at C-10 of dihydrosanguinarine.The methyltransferase, enriched 60-fold and partially characterized, methylates only the hydroxyl moiety at C-10 to form dihydrochelirubine.Both enzymes were found to be highly substrate specific.Key Word Index: Eschscholtzia californica; Papaveraceae; benzophenanthridine alkaloids; dihydroanguinarine-10-hydroxylase; 10-hydroxydihydrosanguinarine-10-O-methyltransferase.