Characteristics and process optimization of cell growth and alpha-amylase production of recombinant Bacillus subtilis.

摘要

he characteristics of cell growth and gene expression, as well as the process optimization of ;In a fed-batch reactor, carbon source can be controlled at a lower level by feeding carbon source continuously, reducing the catabolite repression and improving ;In the culture of recombinant Bacillus subtilis cells, there are two exponential growth phases and cells tend to go into lysis after reaching the maximal cell density. So the diauxic growth mechanism and the effect of growth history of cell evolution are included in the model of growth rate expression. Through model analysis and experimental study, the parameters in the expressions of growth rate and transcription rate are obtained. Also a simulation is carried out by using the model with the estimated parameters. The temporal activation initiated by increasing the temperature improves the specific production rate, resulting in a 30-40 fold increase in the efficiency of transcription compared with the regular culture at normal temperature.;In conclusion, the maximization of