The effect of conformational freedom of side chain on low-frequency motions of amino acids in solid-state

摘要

A comparison of low frequency motions of two amino acids, namely L-threonine and L-valine are made by employing terahertz spectrometer and DFT calculations. Quantitative analyses of the composition of their low-frequency motions are performed. The results suggest that the distortions of dihedral angles of L-threonine dominate intramolecular motions over distortions of bond angles, while the difference between the degrees of distortions of dihedral angles and bond angles of L-valine is much smaller. These observations can be interpreted from the view of conformational freedom of their side chains. (C) 2018 Elsevier B.V. All rights reserved.