Advances in the Prediction of Turn Structures in Peptides and Proteins

Turns are essential for protein structure as they allow the polypeptide chain to fold backup on itself. They also occur within protein binding sites, at proteinprotein interfaces and in small bioactive peptides, where they can play a crucial role for molecular recognition. Turn structures are an important class of protein secondary structure, although relatively little attention is paid to them with respect to helices and β-sheets. Protein structure prediction, functional analysis of proteins and peptides, and computer-aided drug design could all benefit from making use of accurately predicted turn structures from amino acid sequence. Here, recent advances of turn structure prediction and the underlying turn classification will be discussed together with their applications.