pounds is accomplished by means of a biosynthetic pathway which closely parallels the corresponding pathway to cephalosporin C in Cephalosporium acremonium. Two of the enzymes involved in this pathway, deacetoxycephalosporin C (DAOC) synthetase and DAOC hydroxylase, carry out sequential reactions in which penicillin N undergoes ring expansion to DAOC and then DAOC is hydroxylated at the C3 meth...