Department of Chemistry, Technical University of Munich, 85748 Garching, Germany.
WACKER-Chair of Macromolecular Chemistry, Catalysis Research Center, Technical University of Munich, 85748 Garching, Germany.
J Am Chem Soc. 2021 Mar 31;143(12):4782-4789. doi: 10.1021/jacs.1c01148. Epub 2021 Mar 22.
Complex coacervated-based assemblies form when two oppositely charged polyelectrolytes combine to phase separate into a supramolecular architecture. These architectures range from complex coacervate droplets, spherical and worm-like micelles, to vesicles. These assemblies are widely applied, for example, in the food industry, and as underwater or medical adhesives, but they can also serve as a great model for biological assemblies. Indeed, biology relies on complex coacervation to form so-called membraneless organelles, dynamic and transient droplets formed by the coacervation of nucleic acids and proteins. To regulate their function, membraneless organelles are dynamically maintained by chemical reaction cycles, including phosphorylation and dephosphorylation, but exact mechanisms remain elusive. Recently, some model systems also regulated by chemical reaction cycles have been introduced, but how to design such systems and how molecular design affects their properties is unclear. In this work, we test a series of cationic peptides for their chemically fueled coacervation, and we test how their design can affect the dynamics of assembly and disassembly of the emerging structures. We combine them with both homo- and block copolymers and study the morphologies of the assemblies, including morphological transitions that are driven by the chemical reaction cycle. We deduce heuristic design rules that can be applied to other chemically regulated systems. These rules will help develop membraneless organelle model systems and lead to exciting new applications of complex coacervate-based examples like temporary adhesives.
当两种带相反电荷的聚电解质结合形成超分子结构时，就会形成复杂凝聚物基组装体。这些结构的范围从复杂凝聚物液滴、球形和蠕虫状胶束到囊泡。这些组装体被广泛应用于食品工业以及水下或医用粘合剂等领域，但它们也可以作为生物组装体的很好模型。实际上，生物学依赖于复杂凝聚作用来形成所谓的无膜细胞器，这些细胞器是由核酸和蛋白质的凝聚作用形成的动态和瞬时液滴。为了调节它们的功能，无膜细胞器通过包括磷酸化和去磷酸化在内的化学反应循环来动态维持，但确切的机制仍不清楚。最近，一些也受化学反应循环调节的模型系统也被引入，但如何设计这些系统以及分子设计如何影响它们的性质尚不清楚。在这项工作中，我们测试了一系列阳离子肽的化学燃料凝聚作用，并测试了它们的设计如何影响新兴结构的组装和拆卸的动力学。我们将它们与同系物和嵌段共聚物结合，并研究了组装体的形态，包括由化学反应循环驱动的形态转变。我们推导出了可以应用于其他化学调节系统的启发式设计规则。这些规则将有助于开发无膜细胞器模型系统，并为复杂凝聚物基示例（如临时粘合剂）带来令人兴奋的新应用。
