Structural features and conformational equilibria of 3-10-helical peptides in solution by spectroscopic and molecular mechanics studies

The structural features and conformational equilibria of a series of short, linear C-alpha-methylvaline [(alphaMe)Val]-based peptides in methanol were investigated by combining fluorescence resonance energy transfer measurements and molecular mechanics data. IR spectra were employed to determine their secondary structure, which exhibits an intramolecularly H-bonded, 3-10-helix conformation that is affected by backbone distortions that are enhanced by the shortness of the main chain.