BETA-TURN TOPOGRAPHY

The topography of the beta-turn was investigated using 146 examples of beta-turns reported in the literature. Common topographical features were observed across a wide variety of beta-turn types. Based on this, it was proposed that beta-turns could be described in terms of a sing le dihedral angle. which was defined as beta, which provides a complet e description of the spatial relationship between the entry and exit p eptide bonds as well as the relative orientations of the intervening s idechains for any beta-turn. This simplification was made possible by the reduction of the beta-turn structure into two conformationally inv ariant units, the median geometries of which are reported herein. This description should prove particularly useful in the development and a pplication of novel peptide mimetic drugs, compounds for which a class ification based on a peptide backbone geometry may be entirely irrelev ant