Activation volumes in enzymic catalysis: their sources and modification by low-molecular-weight solutes.
Activation volumes in enzymic catalysis: their sources and modification by low-molecular-weight solutes.
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酶催化中的活化体积：它们的来源和低分子量溶质的修饰。
DOI：
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发表时间：
1975
影响因子：
11.1
通讯作者：
G. Somero
中科院分区：
文献类型：
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作者：
P. Low;G. Somero
酶构象的变化往往伴随着体积的巨大变化。模型化合物研究表明，这些体积变化可能来自两个来源：(I)由于改变水密度的蛋白质基团暴露于溶剂中而产生的“水化密度”效应，以及(Ii)由蛋白质本身体积变化引起的“结构”贡献。开发了一种实验方法来检验基于催化构象变化的模型化合物研究的预测的有效性。通过考察不同溶质对不同酶反应的活化体积的影响，我们发现两种体积变化的来源都对活化体积有显著的贡献。
Changes in enzyme conformation are often accompanied by large changes in volume. Model compound studies suggest that these volume changes may derive from two sources: (i) "hydration density" effects due to changes in the exposure to solvent of protein groups which modify water density, and (ii) "structural" contributions arising from changes in the volume of the protein itself. An experimental approach was developed to test the validity of the predictions based on model compound studies for catalytic conformational changes. By examining the effects of different solutes on the activation volumes of different enzymic reactions, we show that both sources of volume change provide significant contributions to the activation volume.