This grant from the Organic Dynamics Program supports the work of Professor Gellman at the University of Wisconsin, Madison. This study will investigate the conformation-directing effects of intramolecular hydrogen bonds that are relevant to protein folding by 1H NMR and IR spectroscopic methods. The specific topics of study are: the intrinsic stability of isolated alpha-helical turns, the postulated helix-initiating role of N-terminal proline residues, the intrinsic stability of beta-hairpins, conformation-specifying effects of ionic peptide appendages, mechanisms of cooperativity among intramolecular hydrogen bonds, and the conformation-directing role of nonpolar-nonpolar interactions (including the hydrophobic effect) in aqueous solution. %%% The results from Professor Samuel H. Gellman's spectroscopic studies will contribute significantly to our understanding of protein folding. The importance of his work is the determination of thermodynamic parameters to assess the relative contributions of hydrophobicity and hydrogen bonding to peptide and protein stability.