标题： 弹性壳体上吸附半刚性聚合物的形状谱 显示英文标题

标题： Shape spectra of elastic shells with surface-adsorbed semiflexible polymers

摘要： 生物壳体的形状，如细胞核、膜和囊泡，由于与多种分子结构的复杂相互作用，通常偏离完美球体。特别是吸附在这些壳体表面的半柔性生物聚合物似乎会影响它们的形态特性。虽然单个长的半柔性链的影响相对较为明确，但高密度的这种表面吸附聚合物如何改变球形软限制的形态，类似于生物壳体，仍然相对较不为人所知。在这里，我们使用粗粒度分子动力学模拟来研究许多半柔性聚合物的表面吸附如何影响加压的珠-弹簧壳体的形态，在没有这些链的情况下该壳体是球形的。通过改变链与壳体表面之间的吸引力强度、链浓度以及链的聚合度，我们证明了强表面定位的链可以引起严重的形状畸变和收缩，这取决于链的长度和浓度。相反，弱定位不会引起显著的形状波动，但在表面上会出现向列有序相。值得注意的是，当弹性壳体由可伸展的谐波键组成时，对于尺寸与约束半径相当或更长的链，这些有序相会导致椭圆形壳体形状。总体而言，我们的研究结果提供了一种通过操控半柔性聚合物的外围定位和长度来控制合成壳体形状的策略，并暗示了某些生物系统中非球形形状出现的机制。 显示英文摘要

摘要： The shape of biological shells, such as cell nuclei, membranes, and vesicles, often deviates from a perfect sphere due to an interplay of complex interactions with a myriad of molecular structures. In particular, semiflexible biopolymers adsorbed to the surfaces of such shells seem to affect their morphological properties. While the effect of a single, long, semiflexible chain is relatively well characterized, the mechanisms by which a high density of such surface-adsorbed polymers can alter the morphology of a spherical, soft confinement, akin to biological shells, remain relatively poorly understood. Here, we use coarse-grained molecular dynamics simulations to investigate how surface adsorption of many semiflexible polymers affects the morphology of a pressurized bead-spring shell, which is spherical in the absence of these chains. By varying the attraction strength between the chains and the shell surface, chain concentration, and the polymerization degree of chains, we demonstrate that strong surface localization of the chains can induce severe shape distortions and shrinkage, depending on the chain length and concentration. Conversely, weak localization does not induce significant shape fluctuations, yet nematically ordered phases appear on the surface. Notably, these ordered phases lead to elliptic shell shapes for chains with sizes comparable to or longer than the radius of the confinement when the elastic shell is composed of extensible, harmonic bonds. Overall, our findings offer a strategy to control the shape of synthetic shells by manipulating peripheral localization and length of semiflexible polymers while suggesting a mechanism for non-spherical shapes appearing in some biological systems.