West Daniel K, Paci Emanuele, Olmsted Peter D
School of Physics and Astronomy and School of Biochemistry and Microbiology, University of Leeds, Leeds LS2 9JT, United Kingdom.
Phys Rev E Stat Nonlin Soft Matter Phys. 2006 Dec;74(6 Pt 1):061912. doi: 10.1103/PhysRevE.74.061912. Epub 2006 Dec 29.
Mechanical unfolding of polyproteins by force spectroscopy provides valuable insight into their free energy landscapes. Most experiments of the unfolding process have been fit to two-state and/or one dimensional models, with the details of the protein and its dynamics often subsumed into a zero-force unfolding rate and a distance x{u}{1D} to the transition state. We consider the entire phase space of a model protein under a constant force, and show that x{u}{1D} contains a sizeable contribution from exploring the full multidimensional energy landscape. This effect is greater for proteins with many degrees of freedom that are affected by force; and surprisingly, we predict that externally attached flexible linkers also contribute to the measured unfolding characteristics.
通过力谱对多聚蛋白进行机械解折叠，为深入了解其自由能景观提供了有价值的见解。大多数解折叠过程的实验都采用了两态和/或一维模型拟合，蛋白质及其动力学细节通常被纳入零力解折叠速率和到过渡态的距离(x_{u}^{1D})中。我们考虑了在恒定力作用下模型蛋白的整个相空间，并表明(x_{u}^{1D})在探索完整的多维能量景观方面有相当大的贡献。对于受作用力影响的具有多个自由度的蛋白质，这种效应更为显著；令人惊讶的是，我们预测外部连接的柔性接头也会对测量的解折叠特性产生影响。
