Kuchel P W, Berthon H A, Bubb W A, Bulliman B T, Collins J G
Department of Biochemistry, University of Sydney, NSW, Australia.
Biomed Biochim Acta. 1990;49(8-9):757-70.
A computer-based model of the metabolism of sugar phosphates by human erythrocytes has been developed to assist in the understanding of the biochemical transformations occurring in the pentose phosphate pathway. These transformations are reflected in the changes, with time, of the relative intensities of the metabolite peaks apparent in 1H, 13C and 31P NMR spectra. The deterministic model consists of 79 reactions interconnected in a defined structure and characterized by 155 rate constants. It also includes 17 different enzymes, 69 enzyme forms, 32 metabolites, and initial value of time and concentration of each of the reactants. The differential equations describing the time-dependence of the concentrations of the reactants are generated and then solved by using the computer program BIOSSIM, which is designed to solve arrays of "stiff" differential equations. We synthesized [1-13C]D-ribose 5-phosphate and used 13C and 31P NMR to monitor its transformation into various intermediates of the pentose phosphate pathway, after the addition of diluted haemolysates which had previously been depleted of nicotinamide- and adenine-nucleotides. The concentrations of several of the reactants were able to be quantified, while other peaks in both the 13C and 31P spectra are yet to be assigned with confidence. There was reasonable qualitative agreement between some aspects of the computer simulation of the proposed metabolic system and the experimental data.
已开发出一种基于计算机的人类红细胞磷酸糖代谢模型，以帮助理解戊糖磷酸途径中发生的生化转化。这些转化反映在1H、13C和31P NMR谱中代谢物峰相对强度随时间的变化上。确定性模型由79个以特定结构相互连接的反应组成，其特征为155个速率常数。它还包括17种不同的酶、69种酶形式、32种代谢物以及每种反应物的时间和浓度初始值。生成描述反应物浓度随时间变化的微分方程，然后使用旨在求解“刚性”微分方程阵列的计算机程序BIOSSIM进行求解。我们合成了[1-13C]D-核糖5-磷酸，并在添加先前已去除烟酰胺和腺嘌呤核苷酸的稀释溶血产物后，使用13C和31P NMR监测其向戊糖磷酸途径各种中间体的转化。几种反应物的浓度能够被定量，而13C和31P谱中的其他峰尚未得到可靠归属。所提出的代谢系统的计算机模拟在某些方面与实验数据之间存在合理的定性一致性。
