Škrbić Tatjana, Hoang Trinh Xuan, Giacometti Achille, Maritan Amos, Banavar Jayanth R
Department of Physics and Institute for Fundamental Science, University of Oregon, Eugene, Oregon 97403, USA and Dipartimento di Scienze Molecolari e Nanosistemi, Università Ca' Foscari di Venezia, Campus Scientifico, Edificio Alfa, via Torino 155, 30170 Venezia Mestre, Italy.
Institute of Physics, Vietnam Academy of Science and Technology, 10 Dao Tan, Ba Dinh, Hanoi 11108, Vietnam.
Phys Rev E. 2021 Jul;104(1):L012101. doi: 10.1103/PhysRevE.104.L012101.
Chain molecules play a key role in the polymer field and in living cells. Our focus is on a new homopolymer model of a linear chain molecule subject to an attractive self-interaction promoting compactness. We analyze the model using simple analytic arguments complemented by extensive computer simulations. We find several striking results: there is a first-order transition from a high-temperature random coil phase to a highly unusual low-temperature phase; the modular ground states exhibit significant degeneracy; the ground state structures exhibit spontaneous dimensional reduction and have a two-layer structure; and the ground states are assembled from secondary motifs of helices and strands connected by tight loops. We discuss the similarities and notable differences between the ground state structures [we call these PoSSuM (Planar Structures with Secondary Motifs)] in the phase and protein native state structures.
链状分子在聚合物领域和活细胞中起着关键作用。我们关注的是一种新型线性链状分子的均聚物模型，该模型存在促进紧密性的吸引性自相互作用。我们使用简单的解析论证并辅以广泛的计算机模拟来分析该模型。我们发现了几个惊人的结果：存在从高温无规线团相到高度异常的低温相的一级转变；模块化基态表现出显著的简并性；基态结构表现出自发的维度缩减并具有双层结构；并且基态由通过紧密环连接的螺旋和链的二级基序组装而成。我们讨论了该相中基态结构[我们将这些称为PoSSuM（具有二级基序的平面结构）]与蛋白质天然态结构之间的相似性和显著差异。
