中文摘要：

以携带多拷贝猪胰岛素前体（PIP）基因的毕赤酵母（Pichia pastoris）为供试菌株,对分批补料发酵PIP合成动力学模型进行研究。建立了不同拷贝数毕赤酵母发酵合成PIP的菌体生长、产物合成和底物消耗的动力学模型,并通过Origin8.0软件对模型参数进行了非线性拟合。根据动力学模型结果发现,随着拷贝数的增加与菌体生长相关的产物系数α和细胞生长代谢系数k1绝对值不断增加,12拷贝时PIP表达量达到最高,说明只有进一步促进高拷贝菌株细胞生长并减少其代谢负担才能更有效地提高产物的生成速率。同时表明：预测值与实验值有良好的拟合性,所建模型能较好地反映分批补料发酵过程PIP的合成。

英文摘要：

Kinetic modelling of recombinant Pichia pastoris harboring multiple porcine insulin precursor（PIP） gene dosages was studied when the cells were grown in the fed-batch culture. The key parameters of this kinetics were estimated, including specific cell growth rate（h^-1）, PIP production rate（g·g^-1·h^-1） and substrate consumption rate（g·g^-1· h^-1）ith nonlinear curve fit by Origin8.0. The results showed that both growth-associated production coefficient（ α） and growth-associated metabolism coefficient（k1） increased with increasing copy numbers. The expression level of PIP reached the highest at the copy number of 12. These results suggested that rapid growth and lower metabolic burden of a high copy number effectively improved the production rate of target proteins. Furthermore, the predicted values based on the established kinetic model were in good agreement with the experimental data, indicating that the kinetic model could be used to describe recombinant PIP production process in fed-batch fermentation mode.