Novel circular dichroism spectroscopic approach for detection of ligand binding of proteins: avidin as example.

TitleNovel circular dichroism spectroscopic approach for detection of ligand binding of proteins: avidin as example.
Publication TypeJournal Article
Year of Publication2009
AuthorsZsila, F
JournalAnal Biochem
Volume391
Issue2
Pagination154-6
Date Published2009 Aug 15
ISSN1096-0309
KeywordsAvidin, Circular Dichroism, Ligands, Protein Binding, Proteins, Spectrophotometry, Ultraviolet
Abstract

Various globular proteins having low or no alpha-helical content exhibit atypical far-ultraviolet (UV) circular dichroism (CD) spectra due to aromatic-aromatic residue and aromatic residue-peptide bond exciton coupling interactions. As a representative example of such proteins, far-UV CD spectra of chicken avidin were recorded before and after the addition of different small molecules. Intensity increase-decrease and/or wavelength shift of the positive CD peak of avidin at 228 nm were observed in the presence of various drugs, dyes, and natural compounds. The results were interpreted by exciton interactions between the aromatic residues of the biotin binding site and the substances bound to it. This novel, fast, microgram (microg) scale approach can be applied for detection of ligand binding of additional proteins displaying avidin-like far-UV CD spectra.

DOI10.1016/j.ab.2009.05.014
Alternate JournalAnal. Biochem.
PubMed ID19450538