On the Structure Elucidation Using Ion Mobility Spectrometry and Molecular Dynamics
On the Structure Elucidation Using Ion Mobility Spectrometry and Molecular Dynamics
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DOI：
10.1021/jp811150q
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发表时间：
2009-07-23
影响因子：
2.9
通讯作者：
Russell, D. H.
中科院分区：
文献类型：
--
作者：
Fernandez-Lima, F. A.;Wei, H.;Russell, D. H.
描述了一种结合离子迁移谱 (IMS) 数据和分子动力学 (MD) 簇分析 (CA) 预测来阐明气相肽离子结构的新方法。新方法基于气相离子结构特征向量（例如结构和总体向量）的确定，这些向量生成气相离子的总构象空间，作为 IMS 实验条件（例如场强、压力、浴气体温度和 IM 单元几何形状）的函数。描述了两种有效采样分子离子气相构象空间作为 IMS 实验的有效离子温度特性函数的方法：(i) 模拟退火 MD-CA-恒温 MD-CA，和 (ii) 广义非玻尔兹曼采样 MD-自由能分析-CA。新的理论方法已成功应用于两种模型肽离子（缓激肽片段1-5和1-8，分别为RPPGF和RPGFSPF），在先前的研究中已提出对有效离子温度敏感的多种构象。
A new approach is described for the elucidation of gas-phase peptide ion structures combining ion mobility spectrometry (IMS) data and molecular dynamics (MD)-cluster analysis (CA) prediction. The new approach is based on the determination of the gas-phase ion structure identity vectors (e.g., structure and population vectors) that generate the total conformational space of the gas-phase ion as a function of the IMS experimental conditions (e.g., field strength, pressure, bath gas temperature, and IM cell geometry). Two methods to efficiently sample the gas-phase conformational space of molecular ions as a function of the effective ion temperature characteristic of the IMS experiments are described: (i) a simulated annealing MD-CA-constant temperature MD-CA, and (ii) a generalized non-Boltzmann sampling MD-free energy analysis-CA. The new theoretical method has been successfully applied to two model peptide ions (Bradykinin fragments 1-5 and 1-8, RPPGF and RPPGFSPF, respectively) for which multiple conformations sensitive to the effective ion temperature have been suggested in previous studies.