Danø S, Hynne F, De Monte S, d'Ovidio F, Sørensen P G, Westerhoff H
Department of Chemistry, Center for Chaos and Turbulence Studies (CATS), H.C. Ørsted Institute, University of Copenhagen, Universitetsparken 5, DK-2100 Ø, Denmark.
Faraday Discuss. 2001(120):261-76; discussion 325-51. doi: 10.1039/b103238k.
The mechanism of active phase synchronization in a suspension of oscillatory yeast cells has remained a puzzle for almost half a century. The difficulty of the problem stems from the fact that the synchronization phenomenon involves the entire metabolic network of glycolysis and fermentation, and consequently it cannot be addressed at the level of a single enzyme or a single chemical species. In this paper it is shown how this system in a CSTR (continuous flow stirred tank reactor) can be modelled quantitatively as a population of Stuart-Landau oscillators interacting by exchange of metabolites through the extracellular medium, thus reducing the complexity of the problem without sacrificing the biochemical realism. The parameters of the model can be derived by a systematic expansion from any full-scale model of the yeast cell kinetics with a supercritical Hopf bifurcation. Some parameter values can also be obtained directly from analysis of perturbation experiments. In the mean-field limit, equations for the study of populations having a distribution of frequencies are used to simulate the effect of the inherent variations between cells.
在振荡酵母细胞悬浮液中，活跃相位同步的机制近半个世纪以来一直是个谜。该问题的难点在于同步现象涉及糖酵解和发酵的整个代谢网络，因此无法在单一酶或单一化学物质的层面上解决。本文展示了如何将连续流动搅拌釜式反应器（CSTR）中的这个系统定量建模为一群通过细胞外介质交换代谢物而相互作用的斯图尔特 - 兰道振荡器，从而在不牺牲生化真实性的情况下降低问题的复杂性。该模型的参数可以通过对具有超临界霍普夫分岔的酵母细胞动力学的任何全尺度模型进行系统展开来推导。一些参数值也可以直接从微扰实验分析中获得。在平均场极限下，用于研究具有频率分布的群体的方程被用来模拟细胞间固有变异的影响。
