GROWTH OF SACCHAROMYCES-CEREVISIAE IS CONTROLLED BY ITS LIMITED RESPIRATORY CAPACITY - FORMULATION AND VERIFICATION OF A HYPOTHESIS
GROWTH OF SACCHAROMYCES-CEREVISIAE IS CONTROLLED BY ITS LIMITED RESPIRATORY CAPACITY - FORMULATION AND VERIFICATION OF A HYPOTHESIS
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DOI：
10.1002/bit.260280620
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发表时间：
1986-06-01
影响因子：
3.8
通讯作者：
KAPPELI, O
中科院分区：
文献类型：
--
作者：
SONNLEITNER, B;KAPPELI, O
提出了一种新的面包酵母在葡萄糖上生长的机理模型。它是基于这样一个事实，即葡萄糖降解通过两个途径在有氧乙醇形成的条件下进行。一部分被氧化代谢，一部分被还原代谢，乙醇是还原能量代谢的最终产物。相应的代谢状态称为氧化还原。乙醇只能氧化使用。氧化葡萄糖和乙醇降解的最大速率由细胞的呼吸能力决定。该模型是制定通过使用纯氧化和还原（发酵）葡萄糖和乙醇代谢的化学计量生长方程。连同实验上可确定的各个代谢途径的产率系数（YX/S），得到的方程系统是充分确定的。所提出的模型的优越性，迄今已出版的是基于两个基本的新颖性。(1)该模型是建立在实验上容易获得的参数。(2)为了模拟需氧乙醇形成，将底物流分成两个同时操作的（即，并行）代谢途径，其表现出不同但恒定的能量产生效率（呼吸和发酵），并因此表现出不同且恒定的生物质产率（YX/S）。该模型允许预测的实验数据，没有参数适应在生物学上可疑的方式。
A novel mechanistic model for the growth of baker''s yeast on glucose is presented. It is based on the fact that glucose degradation proceeds via two pathways under conditions of aerobic ethanol formation. Part is metabolized oxidatively and part reductively, with ethanol being the end product of reductive energy metabolism. The corresponding metabolic state is designated oxidoreductive. Ethanol can be used oxidatively only. Maximum rates of oxidative glucose and ethanol degradation are governed by the respiratory capacity of the cells. The model is formulated by using the stoichiometric growth equations for pure oxidative and reductive (fermentative) glucose and ethanol metabolism. Together with the experimentally determinable yield coefficients (YX/S) for the respective metabolic pathways, the resulting equation system is sufficiently determined. The superiority of the presented model over hitherto published ones is based on two essential novelities. (1) The model was developed on experimentally easily accessible parameters only. (2) For the modeling of aerobic ethanol formation, the substrate flow was split into two simultaneously operating (i.e., in parallel) metabolic pathways that exhibit different but constant energy-generating efficiencies (respiration and fermentation) and consequently different and constant biomass yields (YX/S). The model allows the prediction of experimental data without parameter adaption in a biologically dubious manner.