Hiroyuki Souma, A. Shoji, H. Kurosu
Oct 29, 2008
Citations
0
Influential Citations
6
Citations
Journal
Journal of Molecular Structure
Abstract
Abstract We challenged the problem about the stabilization mechanism of an α-helix formation for polypeptides containing l -proline (Pro) residue. We computed the optimized structure of α-helical poly( l -alanine) molecules including a Pro residue, H-(Ala) 8 -Pro-(Ala) 9 -OH, based on the molecular orbital calculation with density functional theory, B3LYP/6-31G(d) and the 13 C and 15 N chemical shift values based on the GIAO-CHF method with B3LYP/6-311G(d,p), respectively. It was found that two kinds of optimized structures, ‘Bent structure’ and ‘Included α-helix structure’, were preferred structures in H-(Ala) 8 -Pro-(Ala) 9 -OH. In addition, based on the precise 13 C and 15 N chemical shift data of the simple model, we successfully analyzed the secondary structure of well-defined synthetic polypeptide H-(Phe-Leu-Ala) 3 -Phe C -Pro-Ala N -(Phe-Leu-Ala) 2 -OH (FLA-11P), the secondary structure of which was proven to the ‘Included α-helix structure’.