Issue 32, 2007

Intramolecular recognition in a jet-cooled short peptide chain: γ-turn helicity probed by a neighbouring residue

Abstract

γ-Turn, the shortest secondary structure of peptides, exists as two helical forms γL and γD of opposite handedness. The present gas phase study of capped L-Phe-Xxx peptides (Xxx = L-Ala, D-Ala or Aib: aminoisobutyric acid) provides a unique example of intramolecular chiral recognition of the γ-turn helicity on Ala or Aib by the neighbouring residue Phe within the chain. With the chiral L- or D-Ala residues, the presence of a side-chain operates a discrimination between the two helical forms: one of them is widely favoured over the other (γL or γD, respectively). This enables us to validate and calibrate the recognition capabilities of the nearby L-Phe residue. The discriminating interactions have been precisely characterized from their spectroscopic UV and IR signatures and identified by comparison with quantum chemistry calculations. Then, in the case of the non-chiral residue Aib, the two helical forms of the γ-turn, which are simultaneously observed in the jet, have been discriminated and assigned by comparison with the chiral residues. The relative abundances of the diastereomeric forms L-Phe-Aib(γL) and L–Phe-Aib(γD) enable us to determine the most efficient recognition configuration.

Graphical abstract: Intramolecular recognition in a jet-cooled short peptide chain: γ-turn helicity probed by a neighbouring residue

Article information

Article type
Paper
Submitted
26 Mar 2007
Accepted
17 May 2007
First published
20 Jun 2007

Phys. Chem. Chem. Phys., 2007,9, 4491-4497

Intramolecular recognition in a jet-cooled short peptide chain: γ-turn helicity probed by a neighbouring residue

E. Gloaguen, F. Pagliarulo, V. Brenner, W. Chin, F. Piuzzi, B. Tardivel and M. Mons, Phys. Chem. Chem. Phys., 2007, 9, 4491 DOI: 10.1039/B704573E

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements