Elucidation of secondary structures of peptides using high resolution NMR

High resolution two dimensional NMR spectroscopy has become one of the important tools in the elucidation of three dimensional solution structure of fair-sized biomolecules. In this article we summarize the application of 2D NMR techniques to unravel the structure of small proteins and peptides. The basic theme is the systematic identification of the small number of secondary structural motifs such as α-helices, β-sheets and β-turns present in polypeptides using their through bond and through space fingerprints in the 2D NMR correlation maps. The method is illustrated using a 32-residue peptide which corresponds to a calcium-binding domain in the protein calmodulin.