THEORETICAL STUDIES OF DYNAMICAL PROCESSES IN CHEMICAL PHYSICS AND BIOPHYSICS

研究的主要焦点是蛋白质折叠理论和 关于决定反应速率的熵势垒的作用。一 “调查”是对“莱文塔尔悖论”的批判性分析。这个 悖论是，对一个可能的构象进行随机搜索 未折叠的蛋白质将需要宇宙学时间才能到达本原 结构。这表明，这一时间可以缩短为生物学上的 仅通过包括几个数量级的小偏差就可以获得显著的大小 KT，考虑了局部天然构象的影响。另一起调查处理 通过几何瓶颈扩散。结果发现，这是 可以将其描述为扩散过熵 障碍，而不是更常用的势能障碍。一个 第三项研究的动机是通过实验观察 与肌红蛋白结合的配体的粘度依赖性。结果发现，一种 时间波动的熵瓶颈可以在某些方面解释 这些实验。

The main foci of research have been on the theory of protein folding and on the role of entropy barriers in determining reaction rates. One investigation was a critical analysis of "Levinthal's paradox". The paradox is that a random search through possible conformations of an unfolded protein will take cosmological times to arrive at the native structure. It was shown that this time can be reduced to a biologically significant size merely by including a small bias, of the order of a few kT, in factor of locally native conformations. Another investigation dealt with diffusion through geometrical bottlenecks. It was found that this could be described with moderate success as diffusion past entropy barriers instead of the more commonly used potential energy barriers. A third investigation was motivated by experimental observations on the viscosity dependence of ligand binding to myoglobin. It was found that a temporally fluctuating entropy bottleneck can explain some aspects of these experiments.