Quick Prediction Of The Conformation Stability Of Alanine-glycine Peptide

In this work, a special hydrogen method is used to predict the relatively stability of the studied object which is the Alanine-glycine mixed polypeptide molecule and to examine the reliability of the special hydrogen method and its parameters. Using the special hydrogen method on 177 steady conformers which obtained from mixed tri-peptide, mixed tetra-peptide and penta-peptide, and compared with the relative energies with B3LYP/6-31G*, we obtain a satisfactory result. In the total 177 conformers, there are only 8 conformers with deviation more than 2.0 kcal/mol and 38 conformers with deviation between 1.0 kcal/mol and 2.0 kcal/mol. And the population of the conformations with deviation is 4.5% and 21.5% respectively. This work further demonstrates that the special atom plays an important role in determining the conformation stability of polypeptide and the special hydrogen method and parameters are reasonable.