The methylotrophic yeast Pichia pastoris is widely used as a microbial host for recombinant protein production. Bioreactor models for P. pastoris can inform understanding of cellular metabolism and can be used to optimize bioreactor operation. This article constructs an extensive macroscopic bioreactor model for P. pastoris which describes substrates, biomass, total protein, other medium components, and off‐gas components. Species and elemental balances are introduced to describe uptake and evolution rates for medium components and off‐gas components. Additionally, a pH model is constructed using an overall charge balance, acid/base equilibria, and activity coefficients to describe production of recombinant protein and precipitation of medium components. The extent of run‐to‐run variability is modeled by distributions of a subset of the model parameters, which are estimated using the maximum likelihood method. Model prediction from the extensive macroscopic bioreactor model well describes experimental data with different operating conditions. The probability distributions of the model predictions quantified from the parameter distribution are quantifiably consistent with the run‐to‐run variability observed in the experimental data. The uncertainty description in this macroscopic bioreactor model identifies the model parameters that have large variability and provides guidance as to which aspects of cellular metabolism should be the focus of additional experimental studies. The model for medium components with pH and precipitation can be used for improving chemically defined medium by minimizing the amount of components needed while meeting cellular requirements.

中文翻译：

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在确定培养基中生产重组蛋白的毕赤酵母生物反应器的宏观建模

甲基营养酵母毕赤酵母被广泛用作重组蛋白生产的微生物宿主。巴斯德毕赤酵母的生物反应器模型可以为了解细胞代谢提供信息，并可用于优化生物反应器的操作。本文为巴斯德毕赤酵母构建了一个广泛的宏观生物反应器模型它描述了底物、生物质、总蛋白质、其他培养基成分和废气成分。引入物种和元素平衡来描述介质组分和废气组分的吸收和释放速率。此外，使用总电荷平衡、酸/碱平衡和活性系数构建了一个 pH 模型，以描述重组蛋白的产生和培养基成分的沉淀。运行间变异性的程度通过模型参数子集的分布来建模，这些参数使用最大似然法进行估计。来自广泛的宏观生物反应器模型的模型预测很好地描述了具有不同操作条件的实验数据。从参数分布量化的模型预测的概率分布与在实验数据中观察到的运行间变异性可量化地一致。该宏观生物反应器模型中的不确定性描述确定了具有较大可变性的模型参数，并为细胞代谢的哪些方面应成为其他实验研究的重点提供指导。具有 pH 和沉淀的培养基成分模型可用于通过在满足细胞要求的同时最大限度地减少所需成分的数量来改进化学成分确定的培养基。该宏观生物反应器模型中的不确定性描述确定了具有较大可变性的模型参数，并为细胞代谢的哪些方面应成为其他实验研究的重点提供指导。具有 pH 和沉淀的培养基成分模型可用于通过在满足细胞要求的同时最大限度地减少所需成分的数量来改进化学成分确定的培养基。该宏观生物反应器模型中的不确定性描述确定了具有较大可变性的模型参数，并为细胞代谢的哪些方面应成为其他实验研究的重点提供指导。具有 pH 和沉淀的培养基成分模型可用于通过在满足细胞要求的同时最大限度地减少所需成分的数量来改进化学成分确定的培养基。