Wang Li, Yang Zhou, Sheng He, Tianyi Tong, Congsen Wang, Peichen Shi, Suixu Li, Xinchang Wang, Liulin Yang*, Xiaoyu Cao* and Zhong-Qun Tian
In biological systems, molecular assembly primarily relies on the assistance ofmolecular chaperones. Inspired by nature, strategies like ‘chaperone-assisted assem-bly’ and ‘catalyzed assembly’ have been proposed for the sophisticated controlof molecular assembly. Nonetheless, significant challenges remain in the rationaldesign of such systems, calling for a deep understanding of underlying principles.Herein, we demonstrate an artificial chaperone serves a dual role, that is catalystin low dosages and inhibitor in high dosages, in regulating the supramolecularpolymerization of peptides. Low dosages of carboxymethyl cellulose, as the chaper-ones, catalyze the assembly of Aβ16-22peptides into fibrils through multi-step phaseseparation, while high dosages trap the peptides into coacervate intermediates andtherefore inhibit the fibrillation. Consequently, the quantity of chaperones does notfollow the intuition that ‘more is better’ for catalyzing assembly but instead has anoptimal molar ratio. Investigation reveals that the interplay and evolution of electro-static and hydrophobic interactions are the keys to achieving these processes. Thisstudy provides insights into the multifaceted roles artificial chaperones may play ina dosage-dependent manner and enriches the toolkit for efficient and controllableconstruction of complex assembly syste.
Zhi-Chao Lei, Xinchang Wang, Liulin Yang*, Hang Qu, Yibin Sun, Yang Yang, Wei Li, Wen-Bin Zhang, Xiao-Yu Cao, Chunhai Fan, Guohong Li, Jiarui Wu and Zhong-Qun Tian*
Molecular assembly is the process of organizing individual molecules into larger structures and complex systems. The self-assembly approach is predominantly utilized in creating artificial molecular assemblies, and was believed to be the primary mode of molecular assembly in living organisms as well. However, it has been shown that the assembly of many biological complexes is “catalysed” by other molecules, rather than relying solely on self-assembly. In this review, we summarize these catalysed-assembly (catassembly) phenomena in living organisms and systematically analyse their mechanisms. We then expand on these phenomena and discuss related concepts, including catalysed-disassembly and catalysed-reassembly. Catassembly proves to be an efficient and highly selective strategy for synergistically controlling and manipulating various noncovalent interactions, especially in hierarchical molecular assemblies. Overreliance on self-assembly may, to some extent, hinder the advancement of artificial molecular assembly with powerful features. Furthermore, inspired by the biological catassembly phenomena, we propose guidelines for designing artificial catassembly systems and developing characterization and theoretical methods, and review pioneering works along this new direction. Overall, this approach may broaden and deepen our understanding of molecular assembly, enabling the construction and control of intelligent assembly systems with advanced functionality.
Xian-You Liu, Xiao-Yun Yan*, Yuchu Liu, Hang Qu, Yicong Wang, Jing Wang, Qing-Yun Guo, Huanyu Lei, Xing-Han Li, Fenggang Bian, Xiao-Yu Cao, Rui Zhang, Yu Wang, Mingjun Huang, Zhiwei Lin, E. W. Meijer, Takuzo Aida, Xian Kong* and Stephen Z. D. Cheng*
Soft building blocks, such as micelles, cells or soap bubbles, tend to adopt near-spherical geometry when densely packed together. As a result, their packing structures do not extend beyond those discovered in metallic glasses, quasicrystals and crystals. Here we report the emergence of two Frank–Kasper phases from the self-assembly of five-fold symmetric molecular pentagons. The μ phase, an important intermediate in superalloys, is indexed in soft matter, whereas the ϕ phase exhibits a structure distinct from known Frank–Kasper phases in metallic systems. We find a broad size and shape distribution of self-assembled mesoatoms formed by molecular pentagons while approaching equilibrium that contribute to the unique packing structures. This work provides insight into the manipulation of soft building blocks that deviate from the typical spherical geometry and opens avenues for the fabrication of ‘soft alloy’ structures that were previously unattainable in metal alloys.