Accession Number : ADA313397

Title :   The Binding of Oligopeptides to Cyclodextrins: The Role of the Tyrosine Group.

Descriptive Note : Technical rept.,

Corporate Author : STATE UNIV OF NEW YORK AT BUFFALO DEPT OF CHEMISTRY

Personal Author(s) : Bekos, E. J. ; Gardella, J. A., Jr. ; Bright, F. V.

PDF Url : ADA313397

Report Date : AUG 1996

Pagination or Media Count : 34

Abstract : The formation of alpha-cyclodextrin (alpha-CD) and beta-cyclodextrin (beta-CD) inclusion complexes with free tyrosine and the tyrosine residues in two oligopeptides were investigated using steady-state fluorescence spectroscopy. The oligopeptides consist of five amino acids (pentapeptide) and the tyrosine residues are at the n-terminus of both peptides. The two peptides used in this study have specific biological applications and are known to bind selectively to specific receptors. Cyclodextrins were used to model this receptor-peptide (protein-ligand) interaction. Equilibrium binding constants and the enthalpy and entropy of binding were recovered. Molecular size of the tyrosine-containing species and pH (7.0 vs 10.0) were found to have little effect on alpha-CD binding. However, tyrosine binding to beta-CD was dependent on the size (free tyrosine vs. peptide), structure, and pentapeptide conformation.

Descriptors :   *PEPTIDES, *DEXTRINS, *OLIGOMERS, *TYROSINE, STEADY STATE, FLUORESCENCE, SPECTROSCOPY, BIOCHEMISTRY, ENTHALPY, MOLECULAR PROPERTIES, CYCLIC COMPOUNDS, RESIDUES, AMINO ACIDS, ENTROPY, GLUCOSE.

Subject Categories : Biochemistry
      Polymer Chemistry
      Atomic and Molecular Physics and Spectroscopy
      Thermodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE