Manchester Centre for Integrative Systems Biology, Faculty of Life Sciences, Manchester Interdisciplinary Biocentre, The University of Manchester, 131 Princess Street, Manchester M1 7DN, UK.
Biochem Biophys Res Commun. 2011 Feb 18;405(3):388-92. doi: 10.1016/j.bbrc.2011.01.037. Epub 2011 Jan 13.
Enzyme kinetic parameters for rate equations are vital in metabolic network simulation, a major part of systems biology research efforts. Measurements of Michaelis-Menten kinetic parameters Km and Kcat have been performed for enzymes glucose-6-phosphate dehydrogenase (G6P DH) under crowded conditions using molecular crowding agents bovine serum albumin (BSA) and polyethylene glycol (PEG) of 8000 Da molecular weight. An increase in Kcat was observed at very low concentrations of crowding agent, and also at high crowder concentrations when the experiment was performed at 45 °C with PEG. The observed pattern in Kcat for G6P DH at high crowder concentrations has been explained via modelling using excluded volume theory. An increase in rate was observed at 45 °C for G6P DH versus 30 °C; this has been modelled via the Arrhenius equation.
在代谢网络模拟中，酶动力学参数对于速率方程至关重要，这是系统生物学研究工作的主要部分。在拥挤条件下，使用分子拥挤剂牛血清白蛋白（BSA）和分子量为 8000 Da 的聚乙二醇（PEG），对葡萄糖-6-磷酸脱氢酶（G6PDH）的米氏动力学参数 Km 和 Kcat 进行了测量。在非常低的拥挤剂浓度下观察到 Kcat 的增加，并且在实验在 45°C 下用 PEG 进行时，在高拥挤剂浓度下也观察到 Kcat 的增加。通过使用排除体积理论进行建模，解释了在高拥挤剂浓度下 G6PDH 的 Kcat 的观察到的模式。与 30°C 相比，G6PDH 在 45°C 下观察到速率增加；这已通过阿仑尼乌斯方程进行建模。
