Optically-Active Vibrational Spectroscopy of α-Aminoisobutyric Acid Foldamers in Organic Solvents and Phospholipid Bilayers

Research output: Contribution to journalArticle

  • External authors:
  • Maria Giovanna Lizio
  • Valery Andrushchenko
  • Sarah Pike
  • Anna Peters
  • George Whitehead
  • Inigo Vitorica-Yrezabal
  • Shaun Mutter
  • Jonathan Clayden
  • Petr Bour
  • Ewan Blanch

Abstract

Helical α‐aminoisobutyric acid (Aib) foldamers show great potential as devices for the communication of conformational information across phospholipid bilayers, but determining their conformation in bilayers remains a challenge. In the present study, Raman, Raman optical activity (ROA), infrared (IR) and vibrational circular dichroism (VCD) spectroscopies have been used to analyze the conformational preferences of Aib foldamers in solution and when interacting with bilayers. A 310‐helix marker band at 1665‐1668 cm‐1 in Raman spectra was used to show that net helical content increased strongly with oligomer length. ROA and VCD spectra of chiral Aib foldamers provided the chiroptical signature for both left‐ and right‐handed 310‐helices in organic solvents, with VCD establishing that foldamer screw‐sense was preserved when the foldamers became embedded within bilayers. However, the population distribution between different secondary structures was perturbed by the chiral phospholipid. These studies indicate that ROA and VCD spectroscopies are valuable tools for the study of biomimetic structures in phospholipid bilayers, such as artificial signal transduction molecules.

Bibliographical metadata

Original languageEnglish
JournalChemistry: A European Journal
Volume24
Issue number37
Early online date10 May 2018
DOIs
Publication statusPublished - 2 Jul 2018