Cybernetic model of the growth dynamics of Saccharomyces cerevisiae in batch and continuous cultures
Cybernetic model of the growth dynamics of Saccharomyces cerevisiae in batch and continuous cultures
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DOI：
10.1016/s0168-1656(99)00017-6
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发表时间：
1999-05-28
影响因子：
4.1
通讯作者：
Kompala, DS
中科院分区：
文献类型：
--
作者：
Jones, KD;Kompala, DS
在需氧分批培养中，酿酒酵母在葡萄糖上的生长遵循在第一指数生长期期间将葡萄糖完全发酵成乙醇的充分记录的二次生长模式，随后是中间滞后期和消耗乙醇的第二指数生长期。在一系列中间稀释率的连续培养中，酵母生物反应器在所有测量的浓度（如细胞质量、葡萄糖、乙醇和溶解氧）、细胞内储存碳水化合物（如糖原和海藻糖）的量、出芽细胞的分数以及培养物pH中表现出持续的振荡。从“控制论”建模框架开发的酵母生长动力学的非隔离模型，以模拟所有可用代谢途径之间的动态竞争。该控制论模型准确地预测了所有关键的实验观察方面：（i）在分批培养中，中间滞后期的持续时间，乙醇的连续生产和消耗，以及氧气和二氧化碳的气体交换速率的动态;和（ii）在连续培养物中，振荡的自发产生以及当稀释速率或搅拌速率改变时振荡的周期和振幅的变化。(C)1999 Elsevier Science B. V.保留所有权利。
Growth of Saccharomyces cerevisiae on glucose in aerobic batch culture follows the well-documented diauxic pattern of completely fermenting glucose to ethanol during the first exponential growth phase, followed by an intermediate lag phase and a second exponential growth phase consuming ethanol. In continuous cultures over a range of intermediate dilution rates, the yeast bioreactor exhibits sustained oscillations in all the measured concentrations, such as cell mass, glucose, ethanol, and dissolved oxygen, the amounts of intracellular storage carbohydrates, such as glycogen and trehalose, the fraction of budded cells as well as the culture pH. We present here a structured, unsegregated model for the yeast growth dynamics developed from the 'cybernetic' modeling framework, to simulate the dynamic competition between all the available metabolic pathways. This cybernetic model accurately predicts all the key experimentally observed aspects: (i) in batch cultures, duration of the intermediate lag phase, sequential production and consumption of ethanol, and the dynamics of the gaseous exchange rates of oxygen and carbon dioxide; and (ii) in continuous cultures, the spontaneous generation of oscillations as well as the variations in period and amplitude of oscillations when the dilution rate or agitatin rate are changed. (C) 1999 Elsevier Science B.V. All rights reserved.