title: Two-step immobilized enzyme conversion of cephalosporin C to 7-aminocephalosporanic acid.
abstract: The first large-scale production of 7-aminocephalosporanic acid (7ACA) from cephalosporin C (CPC) using a wholly enzymatic synthesis method is reported here. We produced 7ACA from CPC in as high a molar yield as 85% using the immobilized enzymes D-amino acid oxidase (D-AOD) and glutaryl-7-ACA acylase (GL-acylase). In the first reactor, CPC is converted to keto-adipyl-7-aminocephalosporanic acid (keto-7ACA) using an immobilized D-AOD isolated from a yeast, Trigonopsis variabilis. The keto-7ACA is then spontaneously converted to glutaryl-7-aminocephalosporanic acid (GL-7ACA) via a chemical reaction with hydrogen peroxide. The hydrogen peroxide is also a product of the D-AOD reaction. Near quantitative conversion of the keto-7ACA to GL-7ACA was observed. The second reactor converts GL-7ACA to 7ACA using an immobilized GL-acylase, which was isolated from a recombinant Escherichia coli. The final 7ACA crystalline product is a high quality product. The reactions are conducted under very mild aqueous conditions: pH 8.0 and 20 degrees to 25 degrees C. The production of desacetyl side products is minimal. This process is currently being implemented on an industrial scale to produce 7ACA.
authors.affiliation: Biopure Corporation, 11 Hurley Street, Cambridge, MA 02141, USA.
authors.forename: H D
authors.initials: HD
authors.lastname: Conlon
authors.forename: J
authors.initials: J
authors.lastname: Baqai
authors.forename: K
authors.initials: K
authors.lastname: Baker
authors.forename: Y Q
authors.initials: YQ
authors.lastname: Shen
authors.forename: B L
authors.initials: BL
authors.lastname: Wong
authors.forename: R
authors.initials: R
authors.lastname: Noiles
authors.forename: C W
authors.initials: CW
authors.lastname: Rausch