Penicillin biosynthesis. Dual pathways from a modified substrate

Abstract

Preparations of the enzyme isopenicillin N synthetase from Cephalosporium acremonium convert the modified substrate (L-α-amino-δ-adipyl)-L-cysteinyl-D-(α-aminobutyrate) into both penam and cepham products, which have been isolated and their structures established.