Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266061, China.
J Biomol NMR. 2013 Jan;55(1):71-8. doi: 10.1007/s10858-012-9689-3. Epub 2012 Dec 1.
The protein amide (1)H(N) chemical shift temperature coefficient can be determined with high accuracy by recording spectra at different temperatures, but the physical mechanism responsible for this temperature dependence is not well understood. In this work, we find that this coefficient strongly correlates with the temperature coefficient of the through-hydrogen-bond coupling, (3h)J(NC'), based on NMR measurements of protein GB3. Parallel tempering molecular dynamics simulation suggests that the hydrogen bond distance variation at different temperatures/replicas is largely responsible for the (1)H(N) chemical shift temperature dependence, from which an empirical equation is proposed to predict the hydrogen bond thermal expansion coefficient, revealing responses of individual hydrogen bonds to temperature changes. Different expansion patterns have been observed for various networks formed by β strands.
通过在不同温度下记录光谱，可以高精度地确定蛋白质酰胺的（1）H（N）化学位移温度系数，但这种温度依赖性的物理机制尚不清楚。在这项工作中，我们发现该系数与通过氢键耦合的（3h）J（NC'）的温度系数强烈相关，这是基于对蛋白质 GB3 的 NMR 测量得出的。平行淬火分子动力学模拟表明，不同温度/副本下氢键距离的变化在很大程度上导致了（1）H（N）化学位移对温度的依赖性，由此提出了一个经验公式来预测氢键热膨胀系数，揭示了各个氢键对温度变化的响应。在由β链形成的各种网络中观察到了不同的扩展模式。
