标题： 从杂聚物刚度分布到有效均聚物：无序蛋白质的构象分析 显示英文标题

标题： From Heteropolymer Stiffness Distributions to Effective Homopolymers: A Conformational Analysis of Intrinsically Disordered Proteins

摘要： 内在无序蛋白质（IDPs）的特点是缺乏明确的二级和三级结构，因此非常适合在聚合物理论中进行描述。 然而，由于其多样的氨基酸构建块，蛋白质的内在异质性会导致链刚度的局部变化，这可能会影响更大尺度上的构象行为。 为了研究这种影响，我们开发了一个异质蠕虫状链模型，其中局部持久长度遵循高斯分布。 我们证明，这些异质链可以有效地映射到具有单一有效持久长度的均质链。 为了评估这种映射是否可以扩展到天然存在的IDPs，我们使用各种粗粒度IDP模型进行了模拟，发现模拟的IDPs具有类似于相应均质和异质蠕虫状链的形状。 然而，IDPs比理想的蠕虫状链系统性地更大，但在考虑排除体积相互作用时则稍微更紧凑。 我们将这些差异归因于非键合单体之间的分子内相互作用，而我们的理论模型并未考虑这些相互作用。 显示英文摘要

摘要： Intrinsically disordered proteins (IDPs) are characterized by a lack of defined secondary and tertiary structures, and are thus well-suited for descriptions within polymer theory. However, the intrinsic heterogeneity of proteins, stemming from their diverse amino acid building blocks, introduces local variations in chain stiffness, which can impact conformational behavior at larger scales. To investigate this effect, we developed a heterogeneous worm-like chain model in which the local persistence length follows a Gaussian distribution. We demonstrate that these heterogeneous chains can be effectively mapped to homogeneous chains with a single effective persistence length. To assess whether this mapping can be extended to naturally occurring IDPs, we performed simulations using various coarse-grained IDP models, finding that the simulated IDPs have similar shapes like the corresponding homogeneous and heterogeneous worm-like chains. However, the IDPs are systematically larger than ideal worm-like chains, yet slightly more compact when excluded volume interactions are considered. We attribute these differences to intramolecular interactions between non-bonded monomers, which our theoretical models do not account for.