A KINETIC-MODEL FOR THE PENICILLIN BIOSYNTHETIC-PATHWAY IN PENICILLIUM-CHRYSOGENUM

A kinetic model for the first two steps in the penicillin biosynthetic pathway, i.e. the ACV synthetase (ACVS) and the isopenicillin N synth etase (IPNS) is proposed. The model is based on Michaelis-Menten type kinetics with non-competitive inhibition of the ACVS by ACV, and compe titive inhibition of the IPNS by glutathione. The model predicted flux through the pathway corresponds well with the measured rate of penici llin biosynthesis. From the kinetic model the elasticity coefficients and the flux control coefficients are calculated throughout a fed-batc h cultivation, and it is found that there is a shift in the flux contr ol from the ACVS to the IPNS during the cultivation.