Computational Modeling of the Nitrile Stretching Vibration of 5-Cyanoindole in Water
Computational Modeling of the Nitrile Stretching Vibration of 5-Cyanoindole in Water
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DOI：
10.1021/jz900429z
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发表时间：
2010-02-18
影响因子：
5.7
通讯作者：
Gai, Feng
中科院分区：
文献类型：
--
作者：
Waegele, Matthias M.;Gai, Feng
给出了5-氰基色氨酸亚硝酸根（C N）伸缩振动的带宽。在水合作用下显著变宽。因此，它已被提出是一个有用的红外探针的局部水合环境，蛋白质。然而，这种水化引起的光谱增宽的分子机制尚不清楚，使得解释实验结果变得困难。在这里，我们研究如何与各种网站的水的相互作用。通过电子结构/分子动力学方法研究了5-氰基色氨酸侧链5-氰基吲哚对5-氰基色氨酸C-N伸缩振动的影响。研究发现，除了与亚硝酸根基团的相互作用外，水与吲哚环的相互作用也在介导C N伸缩频率中起着重要作用。因此，这项研究提供了一个分子基础，了解水合作用如何影响5-氰基色氨酸的C-N伸缩带。此外，经验模型，其中包括水与亚硝酸根和吲哚基团的相互作用，开发用于预测的C-N伸缩振动带通过分子动力学模拟。
The bandwidth of the nitrite (C N) stretching vibration of 5-cyanotryptophan shows. a significant broadening upon hydration. Thus, it has been proposed to be a useful infrared probe of the local hydration environment,of proteins. However, the molecular mechanism underlying this hydration induced spectral broadening is not known, making interpretation of the experimental results difficult. Herein, we investigate how interactions of water with various sites. of 5-cyanoindole the side chain of 5-cyanotryptophan, affect its C N stretching vibration via a combined electronic structure/molecular dynamics approach. It is found that, besides those interactions with the nitrite group, interactions of water with the indole ring also play a significant role in mediating the C N stretching frequency. Thus, this study provides a molecular basis for understanding how hydration affects the C N stretching band of 5-cyanotryptophan. In addition, an empirical model, which includes interactions of water with both the nitrite and indole groups, is developed for predicting the C N stretching vibrational band via molecular dynamics simulations.