An easy NMR method to study the formation of parallel β-sheets in peptide aggregates

Abstract

There is currently great interest in the study of peptide aggregation by β-sheet formation because of its relevance in pathological states or in the design of self-assembling systems of technological interest. NMR studies of β-sheet aggregates are difficult because of their long correlation times and spectral degeneracy. In this communication we demonstrate the combination of a semiselective TOCSY-NOESY experiment with partial deuterium exchange of labile protons to assign inter-molecular NOE cross peaks and prove the presence of a soluble parallel β-sheet in fast exchange with monomeric Ac-ASTTTNYT-NH2 (Ac-T-NH2) in solution.