Department of Physics, University of Prince Edward Island, Charlottetown, Prince Edward Island, C1A 4P3, Canada.
Department of Physics and Astronomy, California State University, Long Beach, California, 90840, USA.
Soft Matter. 2021 Dec 1;17(46):10505-10515. doi: 10.1039/d1sm01307f.
Recent experiments have elucidated the physical properties of kinetoplasts, which are chain-mail-like structures found in the mitochondria of trypanosome parasites formed from catenated DNA rings. Inspired by these studies, we use Monte Carlo simulations to examine the behavior of two-dimensional networks ("membranes") of linked rings. For simplicity, we consider only identical rings that are circular and rigid and that form networks with a regular linking structure. We find that the scaling of the eigenvalues of the shape tensor with membrane size are consistent with the behavior of the flat phase observed in self-avoiding covalent membranes. Increasing ring thickness tends to swell the membrane. Remarkably, unlike covalent membranes, the linked-ring membranes tend to form concave structures with an intrinsic curvature of entropic origin associated with local excluded-volume interactions. The degree of concavity increases with increasing ring thickness and is also affected by the type of linking network. The relevance of the properties of linked-ring model membranes to those observed in kinetoplasts is discussed.
最近的实验阐明了基体的物理性质，基体是在锥虫寄生虫的线粒体中发现的链式结构，由链状 DNA 环组成。受这些研究的启发，我们使用蒙特卡罗模拟来研究连接环的二维网络（“膜”）的行为。为简单起见，我们仅考虑圆形和刚性的相同环，并且形成具有规则连接结构的网络。我们发现，形状张量本征值随膜尺寸的标度与自回避共价膜中观察到的平坦相的行为一致。增加环的厚度往往会使膜膨胀。值得注意的是，与共价膜不同，连接环膜往往会形成具有内在曲率的凹形结构，这种曲率源于与局部排斥体积相互作用相关的熵。凹度的程度随环厚度的增加而增加，并且还受到连接网络类型的影响。讨论了连接环模型膜的性质与基体中观察到的性质的相关性。
