Modelling 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-phosphate dehydrogenase (GAPDH) production by Escherichia coli C600 galK (GAPDH) have been studied. Using the corresponding observations, an unstructured physiological model has allowed description of the behaviour of the recombinant strain in batch culture on a selective complex medium. This model is characterized by two physiological states (glucose and acetic acid consumption) and is based on the Monod equation applied to the growth rate combined with inhibition by acetate. Since the strain used is genetically engineered, it also incorporates the probability of plasmid loss which has been modelled previously. The model has been applied to a set of batch cultures at varying initial glucose concentrations. According to the simulation results, the model provides an excellent fit to the experimental results.