Enantiomeric peptides self-assembling into fibrils with the same handedness

It is widely accepted that peptides with enantiomeric configurations would self-assemble into nanostructures with opposite supramolecular chirality. However, in this work, we found that the L-peptide polyphenylalanine F10 (FFFFFFFFFF) and its enantiomer f10 displayed mirror image CD spectra, yet both self-assembled into fibers with exclusive left-handedness, a phenomenon also observed in the other two enantiomeric pairs (F9f and f9F, F5f5 and f5F5). Our work provides new insights into the relationship between the molecular chirality of peptide building blocks and the supramolecular chirality of their self-assemblies.