Premium
Structural Characterization of Self‐Assembled Tetra‐Tryptophan Based Nanostructures: Variations on a Common Theme
Author(s) -
Diaferia Carlo,
Balasco Nicole,
Sibillano Teresa,
Giannini Cinzia,
Vitagliano Luigi,
Morelli Giancarlo,
Accardo Antonella
Publication year - 2018
Publication title -
chemphyschem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.016
H-Index - 140
eISSN - 1439-7641
pISSN - 1439-4235
DOI - 10.1002/cphc.201800026
Subject(s) - tryptophan , chemistry , amino acid , polyethylene glycol , peptide , tetra , side chain , aromatic amino acids , peg ratio , self assembly , peptide sequence , stereochemistry , organic chemistry , biochemistry , polymer , finance , medicinal chemistry , gene , economics
Over the years, a large number of multidisciplinary investigations has unveiled that the self‐assembly of short peptides and even of individual amino acids can generate a variety of different biomaterials. In this framework, we have recently reported that polyethylene glycol (PEG) conjugates of short homopeptides, containing aromatic amino acids such as phenylalanine (Phe, F) and naphthylalanine (Nal), are able to form elongated fibrillary aggregates having interesting chemical and physical properties. We here extend these analyses characterizing the self‐assembling propensity of PEG 6 ‐W4, a PEG adduct of the tetra‐tryptophan (W4) sequence. A comprehensive structural characterization of PEG 6 ‐W4 was obtained, both in solution and at the solid state, through the combination of spectroscopic, microscopic, X‐ray scattering and computational techniques. Collectively, these studies demonstrate that this peptide is able to self‐assemble in fibrillary networks characterized by a cross β‐structure spine. The present findings clearly demonstrate that aromatic residues display a general propensity to induce self‐aggregation phenomenon, despite the significant differences in the physicochemical properties of their side chains.