Junier Ivan, Mossa Alessandro, Manosas Maria, Ritort Felix
Programme d'Epigénomique, 523 Terrasses de l'Agora, 91034 Evry, France.
Phys Rev Lett. 2009 Feb 20;102(7):070602. doi: 10.1103/PhysRevLett.102.070602. Epub 2009 Feb 19.
We present a method for determining the free energy of coexisting states from irreversible work measurements. Our approach is based on a fluctuation relation that is valid for dissipative transformations in partially equilibrated systems. To illustrate the validity and usefulness of the approach, we use optical tweezers to determine the free energy branches of the native and unfolded states of a two-state molecule as a function of the pulling control parameter. We determine, within 0.6kBT accuracy, the transition point where the free energies of the native and the unfolded states are equal.
我们提出了一种从不可逆功测量中确定共存态自由能的方法。我们的方法基于一个对部分平衡系统中的耗散变换有效的涨落关系。为了说明该方法的有效性和实用性，我们使用光镊来确定一个两态分子的天然态和未折叠态的自由能分支作为拉动控制参数的函数。我们在0.6kBT的精度范围内确定了天然态和未折叠态自由能相等的转变点。
