Molecular mechanics calculations of the conformers of the dipetide Boc–Gly–Leu–NMe and tripeptide Boc–Gly–Leu–Gly–NMe. Searching the conformational space by the build-up method

Abstract

The sequences of amino acids Gly–Leu and Gly–Leu–Gly frequently recur in elastin, the protein responsible for the elasticity of the tissues of many vertebrates. In this paper we have carried out a theoretical conformational study by molecular mechanics, using a modified version of the build-up method for searching the conformational space, to determine the set of the low-energy conformers for the dipeptide Boc–Gly–Leu–NMe and the tripeptide Boc–Gly–Leu–Gly–NMe. The conformational energy, torsional and H-bond distributions of the conformers, determined by the algorithm, have been calculated. The outcome is successfully compared with experimental and theoretical results.