Jump to main content
Jump to site search


Interactions of aggregating peptides probed by IR-UV action spectroscopy

Abstract

Peptide aggregation, the self-assembly of peptides into structured beta-sheet fibril structures, is driven by a combination of intra- and intermolecular interactions. Here, the interplay between intramolecular and formed inter-sheet hydrogen bonds and the effect of dispersion interactions on the formation of neutral, isolated, peptide dimers is studied by infrared action spectroscopy. Therefore, four different homo- and hetereogenous dimers formed from three different alanine-based model peptides have been formed under controlled and isolated conditions. The peptides differ from one another in the presence and location of a UV chromophore containing cap on either the C- or N-terminus. Conformations of the monomers of the peptides direct the final dimer structure: strongly bonded or folded structures result in weakly bound dimers. Here the intramolecular hydrogen bonds are favored over new intermolecular hydrogen bond interactions. In contrast, linearly folded monomers are the ideal template to form parallel beta-sheet type structures. The weak intramolecular hydrogen bonds present in the linear monomers are replaced by the stronger inter-sheet hydrogen bond interactions. The influence of π-π disperion interactions on the structure of the dimer is minimal, the phenyl rings have the tendency to fold away from the peptide backbone to favour intermolecular hydrogen bond interactions. Quantum chemical calculations confirm our experimental observations.

Back to tab navigation

Supplementary files

Publication details

The article was received on 27 Nov 2018, accepted on 08 Jan 2019 and first published on 08 Jan 2019


Article type: Paper
DOI: 10.1039/C8FD00208H
Citation: Faraday Discuss., 2019, Accepted Manuscript
  •   Request permissions

    Interactions of aggregating peptides probed by IR-UV action spectroscopy

    S. Bakels, E. Meijer, M. Greuell, S. Porskamp, G. Rouwhorst, J. Mahe, M. Gaigeot and A. Rijs, Faraday Discuss., 2019, Accepted Manuscript , DOI: 10.1039/C8FD00208H

Search articles by author

Spotlight

Advertisements