University of Groningen, Groningen Biomolecular Sciences and Biotechnology Institute , Nijenborgh 7, 9747AG Groningen, The Netherlands.
University of Groningen, Center for Systems Chemistry, Stratingh Institute for Chemistry , Nijenborgh 4, 9747AG Groningen, The Netherlands.
ACS Nano. 2017 Aug 22;11(8):7858-7868. doi: 10.1021/acsnano.7b02211. Epub 2017 Jul 21.
Self-replication at the molecular level is often seen as essential to the early origins of life. Recently a mechanism of self-replication has been discovered in which replicator self-assembly drives the process. We have studied one of the examples of such self-assembling self-replicating molecules to a high level of structural detail using a combination of computational and spectroscopic techniques. Molecular Dynamics simulations of self-assembled stacks of peptide-derived replicators provide insights into the structural characteristics of the system and serve as the basis for semiempirical calculations of the UV-vis, circular dichroism (CD) and infrared (IR) absorption spectra that reflect the chiral organization and peptide secondary structure of the stacks. Two proposed structural models are tested by comparing calculated spectra to experimental data from electron microscopy, CD and IR spectroscopy, resulting in a better insight into the specific supramolecular interactions that lead to self-replication. Specifically, we find a cooperative self-assembly process in which β-sheet formation leads to well-organized structures, while also the aromatic core of the macrocycles plays an important role in the stability of the resulting fibers.
分子水平的自我复制通常被认为是生命早期起源的关键。最近，人们发现了一种自我复制的机制，其中复制子的自我组装驱动了这个过程。我们使用计算和光谱技术的组合，对这种自组装自复制分子的一个例子进行了高水平的结构细节研究。对自组装肽衍生复制子堆叠的分子动力学模拟提供了对系统结构特征的深入了解，并为紫外-可见、圆二色性（CD）和红外（IR）吸收光谱的半经验计算提供了基础，这些光谱反映了堆叠的手性组织和肽二级结构。通过将计算光谱与电子显微镜、CD 和 IR 光谱的实验数据进行比较，对两个提出的结构模型进行了测试，从而更好地了解导致自我复制的特定超分子相互作用。具体来说，我们发现了一个协同的自组装过程，其中β-折叠的形成导致了组织良好的结构，而大环的芳香核在纤维的稳定性中也起着重要作用。
