Conformation of peptides of the secretin-VIP-glucagon family in solution

• Published in: Peptides (New York, N.Y. : 1980) Vol. 7; pp. 43 - 48
• Main Authors: Bodanszky, Miklos, Bodanszky, Agnes
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 1986
• Subjects: Amino Acid Sequence; Binding Sites; Conformational analysis; Cyclic analogs of peptide hormones; Glucagon - analogs & derivatives; Peptides, Cyclic - chemical synthesis; Protein Conformation; Receptors, Cell Surface - metabolism; Secondary-tertiary structure; Secretin - analogs & derivatives; Vasoactive Intestinal Peptide - analogs & derivatives; Cyclic analogs of peptide hormones; Secondary-tertiary structure; Conformational analysis
• ISSN: 0196-9781; 1873-5169
• DOI: 10.1016/0196-9781(86)90162-2

The significance of a well defined molecular architecture in hormone receptor interaction and the methods available for the study of preferred conformations are discussed. The conformational freedom in glucagon is a major obstacle in the determination of its biologically relevant geometry. In the secretin molecule intramolecular forces generate a folded, partially helical conformation. In respect of long range cooperative interactions resulting in a compact molecule with secondary-tertiary structure secretin is similar to globular proteins. In VIP some characteristics of secretin and also of glucagon can be recognized. Further progress in conformation analysis can be expected from the study of rigid, cyclic analogs in which the biological activities of the parent hormones are retained or even enhanced. Such analogs have well defined conformations without external stabilization from membrane mimicking lipids. Therefore, they provide information on the biologically relevant geometry of the hormones and contribute also to our knowledge of receptor sites.