Conformational transitions of leucine-containing isomeric sequential basic polytripeptides

✍ Scribed by Štěpánka Štokrová; Miloslav Bohdanecký; Karel Bláha; Jaroslav Šponar

• Book ID: 102763532
• Publisher: Wiley (John Wiley & Sons)
• Year: 1989
• Tongue: English
• Weight: 699 KB
• Volume: 28
• Category: Article
• ISSN: 0006-3525
• DOI: 10.1002/bip.360281007

✦ Synopsis

Synopsis

Conformational transitions of basic sequential polytripeptides (Lys-Ma-Leu),, (Arg-Ala-Ma),, (Arg-Leu-Ala),, and (Arg-Ala-Leu),, induced by elevated salt concentrations and/or temperatures in aqueous solutions, were investigated by CD, sedimentation equilibrium, and viscometry.

The behavior of (Lys-Ala-Leu), was compared with that of the sequential isomer (Lys-Leu-Ala),, studied previously. It was found that both polypeptides are highly helical with a tendency to aggregate in high salt solutions. Although the hydrophobic interactions between Lys and Leu residues play an important role in both cases, the final effect on helix stabilization and aggregation is different. The Arg-containing polypeptides were found to assume the a-helical conformation. Compared to the Lys-containing polypeptides (Lys-Ala-Leu), and (Lys-Leu-Ma),, a very low tendency to aggregate was observed. *We regret to report that Karel Blkha died on August 28, 1987, during the preparation of this article.