%A K Xiong
%A SA Asher
%J Biochemistry
%T Circular dichroism and UV resonance raman study of the impact of alcohols on the gibbs free energy landscape of an ?-helical peptide
%X We used CD and UV resonance Raman spectroscopy to study the impact of alcohols on the conformational equilibria and relative Gibbs free energy landscapes along the Ramachandran ?-coordinate of a mainly poly-Ala peptide, AP with an AAAAA(AAARA)3A sequence. 2,2,2-Trifluoroethanol (TFE) most stabilizes the ?-helix-like conformations, followed by ethanol, methanol, and pure water. The ?-bulge conformation is stabilized more than the ?-helix, while the 310-helix is destabilized due to the alcohol-increased hydrophobicity. Turns are also stabilized by alcohols. We also found that while TFE induces more ?-helices, it favors multiple, shorter helix segments. ? 2010 American Chemical Society.
%N 15
%P 3336 - 3342
%V 49
%D 2010
%R 10.1021/bi100176a
%L pittir17246