Bachmann Michael, Janke Wolfhard
Institut für Theoretische Physik, Universität Leipzig, Augustusplatz 10/11, D-04109 Leipzig, Germany.
Phys Rev Lett. 2003 Nov 14;91(20):208105. doi: 10.1103/PhysRevLett.91.208105.
We present a temperature-independent Monte Carlo method for the determination of the density of states of lattice proteins that combines the fast ground-state search strategy of the new pruned-enriched Rosenbluth chain-growth method and multicanonical reweighting for sampling the complete energy space. Since the density of states contains all energetic information of a statistical system, we can directly calculate the mean energy, specific heat, Helmholtz free energy, and entropy for all temperatures. We apply this method to lattice proteins consisting of hydrophobic and polar monomers, and for the examples of sequences considered, we identify the transitions between native, globule, and random coil states. Since no special properties of heteropolymers are involved in this algorithm, the method applies to polymer models as well.
我们提出了一种与温度无关的蒙特卡罗方法，用于确定晶格蛋白质的态密度，该方法结合了新的剪枝富集罗森布鲁斯链增长方法的快速基态搜索策略和用于对整个能量空间进行采样的多正则重加权。由于态密度包含统计系统的所有能量信息，我们可以直接计算所有温度下的平均能量、比热、亥姆霍兹自由能和熵。我们将此方法应用于由疏水和极性单体组成的晶格蛋白质，并针对所考虑的序列示例，确定天然态、球状态和无规卷曲态之间的转变。由于该算法不涉及杂聚物的特殊性质，该方法也适用于聚合物模型。
