An artificial chaperone serves a dual role in regulating the assembly of peptides through phase separation

In biological systems,molecular assembly primarily relies on the assistance of molecular chaperones.Inspired by nature,strategies like‘chaperone-assisted assembly’and‘catalyzed assembly’have been proposed for the sophisticated control of molecular assembly.Nonetheless,significant challenges remain in the rational design of such systems,calling for a deep understanding of underlying principles.Herein,we demonstrate an artificial chaperone serves a dual role,that is catalyst in low dosages and inhibitor in high dosages,in regulating the supramolecular polymerization of peptides.Low dosages of carboxymethyl cellulose,as the chaperones,catalyze the assembly of Aβ_(16-22) peptides into fibrils through multi-step phase separation,while high dosages trap the peptides into coacervate intermediates and therefore inhibit the fibrillation.Consequently,the quantity of chaperones does not follow the intuition that‘more is better’for catalyzing assembly but instead has an optimal molar ratio.Investigation reveals that the interplay and evolution of electrostatic and hydrophobic interactions are the keys to achieving these processes.This study provides insights into the multifaceted roles artificial chaperones may play in a dosage-dependent manner and enriches the toolkit for efficient and controllable construction of complex assembly systems.

The catassembled generation of naphthalene diimide coordination networks with lone pair-π interactions

Catassembly is a new concept in molecular assembly that is analogous to catalysis in chemical synthesis. However, for most molecular-assembled processes, the catassembler contributions are rather inconspicuous due to the low activation barriers. As a result, few systems dealing with the catassembly are available until now. In this paper, we report that naphthalene diimide coordination networks are formed under the catassembly of lone-pair-bearing catassemblers(e.g., N,N-dimethylacetamide, N-methylpyrrolidin-2-one). During such molecular assembly, a stable transition state between the electron-deficient naphthalene diimide tectons and catassemblers via the less common lone pair-π interactions was observed, which is supposed to play the key role in the enhancement of coordination abilities of organic tectons and thus formation of the final coordination networks.