Hydrogen Bond Energies in Helical Peptides Investigated by Negative Fragmentation Approach with Density Functional Theory

Abstract

Hydrogen bond (H-bond) is an essential factor for the secondary structure formation in proteins. In this review, we will introduce our recent studies in which H-bond interaction energies in three helical secondary structures were systematically analyzed by using the negative fragmentation approach (NFA). We found that the H-bond energies in the helical conformations are weaker than those of the isolated ones. We conclude that H-bond destabilization is originated from the depolarization of the H-bond acceptor and donor groups by their neighboring peptide groups and that the difference of the orientation of neighboring groups cause differences in H-bond energies.