MODELING OF BATCH FERMENTATION OF A RECOMBINANT ESCHERICHIA-COLI PRODUCING GLYCERALDEHYDE-3-PHOSPHATE DEHYDROGENASE ON A COMPLEX SELECTIVE MEDIUM

The kinetics of growth, substrate consumption and glyceraldehyde-3-pho sphate dehydrogenase (GAPDH) production by Escherichia coli C600 galK (GAPDH) have been studied. Using the corresponding observations, an un structured physiological model has allowed description of the behaviou r of the recombinant strain in batch culture on a selective complex me dium. This model is characterized by two physiological states (glucose and acetic acid consumption) and is based on the Monod equation appli ed to the growth rate combined with inhibition by acetate. Since the s train used is genetically engineered, it also incorporates the probabi lity of plasmid loss which has been modelled previously. The model has been applied to a set of batch cultures at varying initial glucose co ncentrations. According to the simulation results, the model provides an excellent fit to the experimental results.