Irbäck Anders, Samuelsson Björn, Sjunnesson Fredrik, Wallin Stefan
Complex Systems Division, Department of Theoretical Physics, Lund University, Lund, Sweden.
Biophys J. 2003 Sep;85(3):1466-73. doi: 10.1016/S0006-3495(03)74579-2.
An atomic protein model with a minimalistic potential is developed and then tested on an alpha-helix and a beta-hairpin, using exactly the same parameters for both peptides. We find that melting curves for these sequences to a good approximation can be described by a simple two-state model, with parameters that are in reasonable quantitative agreement with experimental data. Despite the apparent two-state character of the melting curves, the energy distributions are found to lack a clear bimodal shape, which is discussed in some detail. We also perform a Monte Carlo-based kinetic study and find, in accord with experimental data, that the alpha-helix forms faster than the beta-hairpin.
开发了一种具有简约势的原子蛋白质模型,然后在α-螺旋和β-发夹上进行测试,对这两种肽使用完全相同的参数。我们发现,这些序列的熔解曲线在很好的近似下可以用一个简单的两态模型来描述,其参数与实验数据在合理的定量上一致。尽管熔解曲线具有明显的两态特征,但发现能量分布缺乏清晰的双峰形状,对此进行了一些详细讨论。我们还进行了基于蒙特卡罗的动力学研究,并且与实验数据一致地发现,α-螺旋比β-发夹形成得更快。