Bier M, Bakker B M, Westerhoff H V
Section of Plastic and Reconstructive Surgery, Dept. of Surgery MC 6035, University of Chicago, Chicago, Illinois 60637, USA.
Biophys J. 2000 Mar;78(3):1087-93. doi: 10.1016/S0006-3495(00)76667-7.
Of all the lifeforms that obtain their energy from glycolysis, yeast cells are among the most basic. Under certain conditions the concentrations of the glycolytic intermediates in yeast cells can oscillate. Individual yeast cells in a suspension can synchronize their oscillations to get in phase with each other. Although the glycolytic oscillations originate in the upper part of the glycolytic chain, the signaling agent in this synchronization appears to be acetaldehyde, a membrane-permeating metabolite at the bottom of the anaerobic part of the glycolytic chain. Here we address the issue of how a metabolite remote from the pacemaking origin of the oscillation may nevertheless control the synchronization. We present a quantitative model for glycolytic oscillations and their synchronization in terms of chemical kinetics. We show that, in essence, the common acetaldehyde concentration can be modeled as a small perturbation on the "pacemaker" whose effect on the period of the oscillations of cells in the same suspension is indeed such that a synchronization develops.
在所有通过糖酵解获取能量的生命形式中,酵母细胞是最为基础的一类。在特定条件下,酵母细胞中糖酵解中间产物的浓度会发生振荡。悬浮液中的单个酵母细胞能够使它们的振荡同步,从而相互同相。尽管糖酵解振荡起源于糖酵解链的上部,但这种同步过程中的信号传导物质似乎是乙醛,它是糖酵解厌氧部分底部的一种可透过细胞膜的代谢产物。在此,我们探讨一个问题:一种远离振荡起搏起源的代谢产物如何能够控制同步过程。我们基于化学动力学提出了一个关于糖酵解振荡及其同步的定量模型。我们表明,本质上,共同的乙醛浓度可以被建模为对“起搏器”的一个小扰动,其对同一悬浮液中细胞振荡周期的影响确实使得同步得以发展。