Abstract
The structures of sodiated polyalanine peptides containing 8-12 residues are investigated using infrared multiple photon dissociation (IRMPD) spectroscopy and classical and quantum modeling. Calculations indicate that the α-helical structure is the most stable conformation for the peptides whatever their size. The IRMPD spectra provide evidence for the coexistence of helical and globular shapes for Ala8Na+, and possibly for Ala9Na+. The turning point from globule to helix is thus found at Ala8-9Na+. The N-H and O-H stretching region allows identifying a new spectroscopic pattern typical for α-helical structures of polyalanines.
| Original language | English |
|---|---|
| Pages (from-to) | 3320-3324 |
| Number of pages | 5 |
| Journal | Journal of Physical Chemistry Letters |
| Volume | 3 |
| Issue number | 22 |
| DOIs | |
| Publication status | Published - 15 Nov 2012 |
| Externally published | Yes |