HELICAL PREFERENCES OF ALANINE, GLYCINE, AND AMINOISOBUTYRIC HOMOPEPTIDES

The stability between helical conformations of homopeptides of alanine , glycine, and aminoisobutyric acid has been studied by means of quant um-mechanical methods. The influence of peptide length on the relative stability between helical conformations has also been analyzed by mea ns of systematic studies for peptides of size up to 11 residues. Final ly, the influence of the solvent has been examined by using self-consi stent reaction field methods. The results provide a detailed picture o f the modulation exerted by these factors on the helical preferences o f these peptides. (C) 1997 Wiley-Liss, Inc.