Effect of Achiral Glycine Residue on the Handedness of Surfactant-Like Short Peptide Self-Assembly Nanofibers

JQ Wang and DB Yang and K Qi and SK Lai and XH Li and XF Ju and WL Liu and CY He and D Wang and YR Zhao and YB Ke and H Xu, LANGMUIR, 39, 9932-9941 (2023).

DOI: 10.1021/acs.langmuir.3c01165

Surfactant-likeshort peptides are a kind of ideal model for thestudy of chiral self-assembly. At present, there are few studies onthe chiral self-assembly of multicharged surfactant-like peptides.In this study, we adopted a series of short peptides of Ac-I(4)KGK-NH2 with different combinations of L-lysine and D-lysine residues as the modelmolecules. TEM, AFM and SANS results showed that Ac-I-4 ( L )KG( L )K-NH2, Ac-I-4 ( L )KG( D )K-NH2, and Ac-I-4 ( D )KG( L )K-NH2 formed themorphologies of nanofibers, and Ac-I-4 ( D )KG( D )K-NH2 formed nanoribbons.All the self-assembled nanofibers, including the intermediate nanofibersof Ac-I-4 ( D )KG( D )K-NH2 nanoribbons, showed the chirality of lefthandedness. Based on the molecular simulation results, it has beendemonstrated that the supramolecular chirality was directly dictatedby the orientation of single & beta; strand. The insertion of glycineresidue demolished the effect of lysine residues on the single strandconformation due to its high conformational flexibility. The replacementof L-isoleucine with Da-isoleucinealso confirmed that the isoleucine residues involved in the & beta;-sheetdetermined the supramolecular handedness. This study provides a profoundmechanism of the chiral self-assembly of short peptides. We hope thatit will improve the regulation of chiral molecular self-assembly withachiral glycine, as well.

Return to Publications page