A short Aib/Ala-based peptide helix is as stable as an Ala-based peptide helix double its length.

Abstract

Highly helical short peptides: A 14-mer Aib-/Ala-based peptide (∼20 % Aib and ∼40 % Ala) helix at 25 °C showed stability similar to that of an Ala-based peptide (∼60 % Ala) helix almost twice its length at 0 °C (see figure). The quantitative comparison between helix stabilities of Ala- and Aib/Ala-based peptide has important implications for the use of the Aib/Ala strategy in the design of short helical peptides.