Lipid-induced conformational changes in glucagon, secretin, and vasoactive intestinal peptide

✍ Scribed by Randall M. Robinson; Ernest W. Blakeney Jr.; Wayne L. Mattice

• Book ID: 102761140
• Publisher: Wiley (John Wiley & Sons)
• Year: 1982
• Tongue: English
• Weight: 672 KB
• Volume: 21
• Category: Article
• ISSN: 0006-3525
• DOI: 10.1002/bip.360210615

✦ Synopsis

Abstract

The CD of glucagon, secretin, and vasoactive intestinal peptide has been studied as a function of temperature in water and in aqueous solutions of dodecyl sulfate, phosphatidyl glycerol, and L‐α‐phosphatidic acid (dipalmitoyl). The anionic detergent and lipids induce helix formation in all three peptides, with the amount of induced helical content increasing in the order glucagon < secretin < vasoactive intestinal peptide. These observations are subject to quantitative rationalization using a matrix formulation for the configuration partition function. In this formulation the major conformational consequences of the interaction with anionic lipids or detergents is an increase in the probability for helix formation by arginyl, histidyl, and lysyl residues. The region in which helix formation is maximal is found to be at amino acid residues 13–20 in all three peptides. Other studies have implicated this portion of the polypeptide chain in receptor binding. Thus, the helical segment induced by interaction with anionic lipids may play an important physiological role.