NMR study of 1:1 complexes between divalent sulfur and aromatic compounds: A model for interactions in globular proteins

Abstract

The existence of 1:1 complexes between various divalent sulfur and aromatic compounds in CCl 4 solution is demonstrated by the method of Job. By making measurements at different temperatures we find that the heat of complex formation is close to 1 kcal/mol. We propose that this interaction, which is stronger than that due to van der Waals' forces alone, be included in attempts to calculate the energy of native proteins or to predict the folding of polypeptide chains.