Department of Chemistry, State University of New York at Stony Brook, Stony Brook, New York 11794, USA.
J Phys Chem B. 2013 Apr 25;117(16):4661-9. doi: 10.1021/jp309122b. Epub 2013 Apr 5.
Protein folding is one of the most fundamental problems in modern molecular biology. Uncovering the detailed folding mechanism requires methods that can monitor the structures at high temporal and spatial resolution. Two-dimensional infrared (2DIR) spectroscopy is a new tool for studying protein structures and dynamics with high time resolution. Using atomistic molecular dynamics simulations, we illustrate the folding process of Trp-cage along the dominant pathway on the free energy landscape by analyzing nonchiral and chiral coherent 2DIR spectra along the pathway. Isotope labeling is used to reveal residue-specific information. We show that the high resolution structural sensitivity of 2DIR can differentiate the ensemble evolution of protein and thus provides a microscopic picture of the folding process.
蛋白质折叠是现代分子生物学中最基本的问题之一。揭示详细的折叠机制需要能够在高时间和空间分辨率下监测结构的方法。二维红外（2DIR）光谱是一种新的研究工具，用于研究具有高时间分辨率的蛋白质结构和动力学。我们使用原子分子动力学模拟，通过分析沿路径的非手性和手性相干 2DIR 光谱，沿着自由能景观的主导途径，阐明 Trp-cage 的折叠过程。同位素标记用于揭示残基特异性信息。我们表明，2DIR 的高分辨率结构灵敏度可以区分蛋白质的整体演化，从而提供了折叠过程的微观图像。
