title: Immobilization of digitoxin 12β-hydroxylase, a cytochrome P-450-dependent enzyme from cell cultures of Digitalis lanata EHRH.
abstract: Attempts were made to immobilize digitoxin 12β-hydroxylase, a membrane-bound, cytochrome P-450-dependent monooxygenase from cell cultures of Digitalis lanata. The optimum procedure was the entrapment of microsomes in 2% alginate by crosslinking the polysaccharide chains with CaCl2. After the immobilization of the enzyme about 70% of its activity was retained. The kinetic data such as the pH optimum and the optimum substrate concentrations were identical for the immobilized enzyme and freely suspended microsomes. Using β-methyldigitoxin as a substrate enzyme activity could be observed for more than 20 h. A continuous flow system for immobilized digitoxin 12β-hydroxylase is described.
authors.affiliation: Institut für Biologie I, Auf der Morgenstelle 1, D-7400, Tübingen, Federal Republic of Germany.
authors.forename: M
authors.initials: M
authors.lastname: Petersen
authors.forename: A W
authors.initials: AW
authors.lastname: Alfermann
authors.forename: E
authors.initials: E
authors.lastname: Reinhard
authors.forename: H U
authors.initials: HU
authors.lastname: Seitz