π-System Functionalization Transforms Amyloidogenic Peptide Fragment of Human Islet Amyloid Polypeptide into a Super Hydrogelator

Chem Asian J. 2023 Feb 14;18(4):e202201235. doi: 10.1002/asia.202201235. Epub 2023 Jan 11.

Abstract

While a considerable number of ultra-short/short amyloid peptides have been reported to form 3D supramolecular hydrogels, they all possess high minimum gelation concentration (MGC) (≥1 wt%), which preclude their applications. In this context, we demonstrate that functionalisation of a well-known amyloidogenic ultra-short peptide fragment NFGAIL (IAPf) of human Islet amyloid polypeptide with a π-system (Fluorenyl, Fm) at the N-terminus of the peptide (Fm-IAPf) yield not only highly thermostable hydrogel at physiological pH but also exhibited super gelator nature as the MGC (0.08 wt%) falls below 0.1 wt%. Various experimental results confirmed that aromatic π-π interactions from fluorenyl moieties and hydrogen bonding interactions between the IAPf drive the self-assembly/fibril formation. Fm-IAPf is the first super hydrogelator derived from amyloid-based ultra-short peptides, to the best of our knowledge. We strongly believe that this report, i. e., functionalization of an amyloid peptide with π-system, provides a lead to develop super hydrogelators from other amyloid-forming peptide fragments for their potential applications.

Keywords: IAPP; Islet amyloid; hydrogel; super gelator; supramolecular.

MeSH terms

  • Amyloid / chemistry
  • Humans
  • Islet Amyloid Polypeptide* / chemistry
  • Peptide Fragments* / chemistry

Substances

  • Peptide Fragments
  • Islet Amyloid Polypeptide
  • Amyloid