title: Cell wall localization of dihydroflavonol-glucoside β-glucosidase in flowers of Petunia hybrida.
abstract: Limbs of flower buds from Petunia hybrida were investigated for β-glucosidase activity with dihydroflavonol-glucosides and 4-methyl-umbelliferyl-β-D-glucoside as substrates. Dihydroflavonol-glucoside β-glucosidase is localized in the cell wall. This activity has an acid pH optimum and is also active toward 4-methyl-umbelliferyl-β-glucoside. Besides this activity a neutral β-glucosidase is present. This activity is soluble and is not active toward dihydroflavonol-glucosides. Using starch gel electrophoresis it was shown that no difference in β-glucosidase activity is present between mutants able to convert dihydroflavonols into anthocyanins and mutants accumulating dihydroflavonol-glucosides. It is concluded that β-glucosidase activity is not involved in anthocyanin synthesis.
authors.affiliation: Section Biosynthesis of Flavonoids, Departments of Genetics and Plant Physiology, University of Amsterdam, Kruislaan 318, NL-1098 SM, Amsterdam, The Netherlands.
authors.forename: A W
authors.initials: AW
authors.lastname: Schram
authors.forename: E J
authors.initials: EJ
authors.lastname: Al
authors.forename: N
authors.initials: N
authors.lastname: Douma
authors.forename: L M
authors.initials: LM
authors.lastname: Jonsson
authors.forename: P
authors.initials: P
authors.lastname: de Vlaming
authors.forename: A
authors.initials: A
authors.lastname: Kooi
authors.forename: G J
authors.initials: GJ
authors.lastname: Bennink