Aromatic stacking facilitated self-assembly of ultra-short ionic complementary peptide sequence: β-sheet nanofibres with remarkable gelation and interfacial properties

DOI: 10.1021/acs.biomac.0c00366

Authors: Jacek K. Wychowaniec (University of Manchester; Manchester Institute of Biotechnology; University College Dublin) , Ronak Patel (University of Central Lancashire) , James Leach (University of Central Lancashire) , Rachel Mathomes (University of Central Lancashire) , Vikesh Chhabria (University of Central Lancashire) , Yogita Patil-Sen (University of Central Lancashire) , Araida Hidalgo-Bastida (Manchester Metropolitan University) , Robert T. Forbes (University of Central Lancashire) , Joseph M. Hayes (University of Central Lancashire) , Mohamed A. Elsawy (University of Manchester; Manchester Institute of Biotechnology; University of Central Lancashire; De Monfort University)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Biomacromolecules

State: Published (Approved)
Published: May 2020
Diamond Proposal Number(s): 17102

Abstract: Understanding peptide self-assembly mechanisms and stability of the formed assemblies is crucial for development of functional nanomaterials. Herein, we have adopted rational design approach to demonstrate how minimal structural modification to a non-assembling ultra-short ionic self-complementary tetrapeptide FEFK (Phe4) remarkably enhanced stability of self-assembly into β-sheet nanofibres and induced hydrogelation. This was achieved by replacing flexible phenylalanine residue (F) by the rigid phenylglycine (Phg) resulting in constrained analogue PhgEPhgK (Phg4), which positioned aromatic rings in an orientation favourable for aromatic stacking. Phg4 self-assembly into stable β-sheet ladders was facilitated by π-staking of aromatic sidechains alongside hydrogen bonding between backbone amides along the nanofibre axis. The contribution of these non-covalent interactions in stabilising self-assembly was predicted by in silico modelling using molecular dynamics simulations and semi-empirical quantum mechanics calculations. In aqueous medium, Phg4 β-sheet nanofibres entangled at a critical gelation concentration > 20 mg/mL forming a network of nanofibrous hydrogel. Phg4 also demonstrated unique surface activity in presence of immiscible oils and was superior to commercial emulsifiers in stabilising oil-in-water emulsions. This was attributed to interfacial adsorption of amphiphilic nanofibrilles forming nanofibrillised microspheres. To our knowledge, Phg4 is the shortest ionic self-complementary peptide rationally designed to self-assemble into stable β-sheet nanofibres capable of gelation and emulsification. Our results suggest that Ultra-short Ionic-complementary Constrained Peptides or UICPs have significant potential for the development of cost-effective, sustainable and multifunctional soft bionanomaterials.

Journal Keywords: Peptides; self-assembly; β-sheet; phenylglycine; hydrogels; emulsions

Subject Areas: Biology and Bio-materials, Chemistry


Instruments: I22-Small angle scattering & Diffraction

Documents:
acs.biomac.0c00366.pdf

Discipline Tags:

Biochemistry Biomaterials Chemistry Life Sciences & Biotech Material Sciences Nanoscience/Nanotechnology Organic Chemistry

Technical Tags:

Scattering Small Angle X-ray Scattering (SAXS)