Studies on β‐turn of peptides

Abstract
The effect of changing 1st and 4th amino acid residues on β‐turn preference of tetrapeptide sequences was studied by use of CD spectra of the chromophoric derivatives, which have Dnp‐ and pNA‐groups as the amino and carboxyl substituents, respectively. The effect was examined with the tetrapeptides having such sequences at the 2nd and 3rd positions as ‐L‐Pro‐L‐Asn‐, ‐L‐Pro‐Gly‐, ‐L‐Pro‐D‐Ala‐, ‐L‐Ala‐D‐Leu‐, ‐L‐Ala‐L‐Pro‐, and ‐D‐Ala‐L‐Pro‐. The β‐turn preferences estimated from the CD intensities of the bands due to exciton interaction were found to depend largely on the configurations of the 1st and 4th amino acid residues. When 1st and 2nd (or 3rd and 4th) residues had the same configuration, decreased intensity of the CD band was observed even if the internal sequence had high β‐turn preference. Terminal Gly residues were favorable for the β‐turn conformation in many of the tetrapeptide sequences examined.

This publication has 11 references indexed in Scilit: