酿酒酵母糖酵解途径的动态模拟

Dynamic modeling glycolysis pathway of Saccharomyces cerevisiae

利用葡萄糖脉冲对酿酒酵母厌氧连续培养物施加扰动,通过不同时间点取样,定量细胞内外主要化合物的含量。利用测定的数据和细胞内糖酵解途径模型进行各反应途径的参数估计,结果发现实际测量值与预测值接近。代谢控制分析发现,糖酵解途径中,磷酸果糖激酶、己糖激酶和己糖转运系统具有较大的通量控制系数。随机改变细胞内外化合物的浓度对细胞能荷状态的模拟结果显示,酿酒酵母能在1min内将细胞的能荷状态恢复到初始水平。

A glucose pulse was exerted on the continuous culture of Saccharomyces cerevisiae.The major intercellular metabolites were determined from cultures sampled at different time points.Parameter estimation was conducted using the quantitation data and a glycolysis model,which showed agood match of the observed and calculated results.Metabolic control analysis showed that hexose transport system,hexose kinase and phosphofructokinase had high flux control coefficients.Simulation result performed by randomly changing the inter-and intra-cellular concentrations of the metabolites indicated that cells could restore their energy charge states within one minute.