Conformations of macromolecular sequential polypeptides in solution: 2. Sequential polypeptides containing both d- and l-residues

The conformations adopted in solution by two series of macromolecular sequential polypeptides containing up to four γ-benzyl-d-glutamyl and one γ-benzyl-l-glutamyl or l-leucyl residue in the repeating unit have been studied by spectroscopic methods (i.r., o.r.d., n.m.r.). The nature of the ordered conformations encountered is discussed; it is suggested that they are a distorted form of the α-helix and special types of cross β-structure.