Hjortso M A, Nielsen J
Chemical Engineering Louisiana State University, Baton Rouge, USA.
J Biotechnol. 1995 Oct 16;42(3):255-69. doi: 10.1016/0168-1656(95)00086-6.
Autonomous oscillations in continuous microbial cultures is well documented for the case of baker's yeast, Saccharomyces cerevisiae, for which it has been observed under a range of operating conditions. We have found that autonomous microbial oscillations can be modeled by unstructured population balance models in which a key cell cycle parameter is a function of the environmental conditions, e.g., the concentration of a substrate or product. Although these models are remarkably simple, they can display a wide range of dynamic behaviors. These behaviors include, for binary fission organisms, solutions containing a single synchronous population and, for budding yeasts, two synchronized subpopulations with a period of oscillation similar to that of the cell cycle length, a pattern that has been observed experimentally in S. cerevisiae. Numerical simulations of the model equations also show that complex periodic solutions with periods very different from the cell cycle length are possible. The ability of the population balance approach to accurately describe the available data of yeast culture dynamics will be discussed.
在连续微生物培养中，面包酵母（酿酒酵母）的自主振荡已有充分记录，在一系列操作条件下都观察到了这种现象。我们发现，自主微生物振荡可以用非结构化群体平衡模型来模拟，其中一个关键的细胞周期参数是环境条件的函数，例如底物或产物的浓度。尽管这些模型非常简单，但它们可以表现出广泛的动态行为。对于二分裂生物，这些行为包括包含单个同步群体的解；对于出芽酵母，则包括两个同步亚群体，其振荡周期与细胞周期长度相似，这种模式已在酿酒酵母中通过实验观察到。模型方程的数值模拟还表明，可能存在周期与细胞周期长度非常不同的复杂周期解。将讨论群体平衡方法准确描述酵母培养动力学现有数据的能力。
