Sorribas A, Curto R, Cascante M
Departament de Ciències, Mèdiques Bàsiques, Facultat de Medicina (Lleida), Universitat de Barcelona, Spain.
Math Biosci. 1995 Nov;130(1):71-84. doi: 10.1016/0025-5564(94)00094-g.
In the first two papers of this series (immediately preceding, this issue), we characterized the steady-state properties of a model of a fermentation pathway in Saccharomyces cerevisiae in four experimental conditions. In each of these conditions, the pictures obtained by metabolic control analysis and biochemical systems theory were coincident, which illustrates the relatedness of the two approaches. In this paper we analyze the quality of this description by means of the tools available within biochemical systems theory, and we show that in some of the experimental conditions studied the system is poorly characterized. The most critical condition corresponds to the immobilization of the cells at pH 5.5, in which the kinetic characterization appears to be inaccurate. Furthermore, sensitivity analysis and the study of the local steady-state stability identify the most critical parameters. The results of these analyses are confirmed by the predictions of the dynamic response of the model using its S-system representation. This illustrates the utility of these tools and warns against using the steady-state characterization without testing its validity.
在本系列的前两篇论文（紧接本期之前）中，我们在四种实验条件下对酿酒酵母发酵途径模型的稳态特性进行了表征。在每种条件下，通过代谢控制分析和生化系统理论获得的结果是一致的，这说明了两种方法的相关性。在本文中，我们借助生化系统理论中可用的工具分析了这种描述的质量，并表明在所研究的某些实验条件下，该系统的特征描述不佳。最关键的条件对应于在pH 5.5下固定化细胞，其中动力学表征似乎不准确。此外，敏感性分析和局部稳态稳定性研究确定了最关键的参数。使用其S系统表示对模型的动态响应进行预测，证实了这些分析的结果。这说明了这些工具的实用性，并提醒不要在未测试其有效性的情况下使用稳态表征。
