Co‐Assembly between Fmoc Diphenylalanine and Diphenylalanine within a 3D Fibrous Viscous Network Confers Atypical Curvature and Branching

Abstract

Supramolecular polymer co‐assembly is a useful approach to modulate peptide nanostructures. However, the co‐assembly scenario where one of the peptide building blocks simultaneously forms a hydrogel is yet to be studied. Herein, we investigate the co‐assembly formation of diphenylalanine (FF), and Fmoc‐diphenylalanine (FmocFF) within the 3D network of FmocFF hydrogel. The overlapping peptide sequence between the two building blocks leads to their co‐assembly within the gel state modulating the nature of the FF crystals. We observe the formation of branched microcrystalline aggregates with an atypical curvature, in contrast to the FF assemblies obtained from aqueous solution. Optical microscopy reveal the sigmoidal kinetic growth profile of these aggregates. Microfluidics and ToF‐SIMS experiments exhibit the presence of co‐assembled structures of FF and FmocFF in the crystalline aggregates. Molecular dynamics simulation was used to decipher the mechanism of co‐assembly formation.

Anatomy and formation mechanisms of early amyloid-β oligomers with lateral branching: graph network analysis on large-scale simulations

“…Lateral branching was also observed in recent studies of shorter peptide fragment (2-7 amino acids) self-assembly through simulations of hundreds of interacting peptides. [83][84][85] These studies, together with ours, highlight the need to include enough peptide chains in self-assembly simulations to observe events like oligomer branching, which takes place on a longer length scale than small oligomer formation. 86,87 We have elucidated how Aβ coordination properties dictate topological and geometric features of resulting AβOs.…”

Dipeptide Nanostructure Assembly and Dynamics via in Situ Liquid-Phase Electron Microscopy

“…Mosaic mapping on a 0.5 mm × 0.5 mm area surrounding the irradiated window was performed on each irradiated liquid-cell chip to yield a secondary ion map of the SiN x surface. The m / z peaks of interest corresponding to FF and its fragments are m / z 77, 91, 120, 165, and 312 (Figure A) . Mass-filtered secondary ion maps at m / z 312 ± 1 further reveal the location and morphology of FF nanotubes (Figure B, Figure S11).…”

“…Mass-filtered secondary ion maps at m / z 312 ± 1 further reveal the location and morphology of FF nanotubes (Figure B, Figure S11). Notably, the signal intensity of FF molecules shows a change in the intensity of peaks within the fragmentation pattern even under low flux conditions (Figure C, Figure S12). The mass difference on the irradiated liquid-cell chips is also evident on the secondary ion maps, such that the distinct morphology of FF nanotubes is not visible at m / z 312 ± 1, suggesting molecular level damage across the nanotubes even under low flux conditions (Figures S13 and S14).…”

Repair of Peripheral Nerve Injury Using Hydrogels Based on Self-Assembled Peptides

“…What is more, aromatic interactions can effectively influence the properties of hydrogels. For example, the diphenylalanine hydrogels exhibit higher stiffness due to aromatic stacks [41]. Besides, further addition of konjac glucomannan to the diphenylalanine hydrogel can also control the release rate of the contents [42].…”