Solubilities of the αII- and β-Forms of Synthetic Polypeptides: Evidence for an αII–β Transformation in the Amorphous Phase

IN previous communications1,2from these Laboratories, it has been shown that the molecular chains of a number of synthetic polypeptides can exist in folded and extended configurations, and the X-ray and infra-red evidence which has accumulated so far is entirely consistent with the view that the folded form has the αII-structure proposed by Ambrose and Hanby3. One purpose of this note is to bring forward evidence of a different kind which has a bearing on the structure of the molecular fold.