Effect of α-Helix Neuropeptide on the Self-Assembly Behavior of β-Sheet Amyloid Short Peptides

Peptide self-assembly is a promising process in which the conformations formed during dynamic stages play a crucial role in determining the resulting self-assembly morphologies and structural parameters. These unique conformations also hold potential for the de novo design of supramolecular peptide nanomaterials with tailored properties. In this work, we explore the impact of incorporating an α-helix neuropeptide Y fragment (NPY_21-27) into amyloid peptide EFFE, focusing on its influence on β-sheet self-assembly. Microscopic imaging and spectroscopic analyses reveal that W2 and W4 peptides form twisted nanofibers based on β-sheet structures, with W4 displaying periodic helical structures. The charged amino acids promote a pH-dependent self-assembly, accompanied by ion coordination behaviors. Notably, the chirality modulation between EFFE and NPY_21-27 in W2 induces a structural transition from twisted nanofibers to nanotubes, influenced by molecular orientation and spatial alignment. These findings provide a foundation for rational design of peptide nanomaterials with controlled conformations and structures.