(Gd3+) Complexation with oligopeptide (SFVG) and amyloid peptide (Aβ13–23) in aqueous solution by NMR spectroscopy

Abstract

Gadolinium (III) ion, which belongs to the subgroup of transition metal ions, has practical importance for magnetic resonance imaging (MRI) with contrast. The accumulation of complexes of transition metal ions with amyloid peptides in the human body leads to the formation of insoluble plaques, which are presumably-one of the causes of Alzheimer's disease. This paper presents the results of studying the interaction of the gadolinium (III) ion with a fragment of amyloid protein Aβ40 in aqueous solutions using nuclear magnetic resonance spectroscopy. Tetrapeptide (SFVG) was used as the simplified model of metal-peptide interaction research. Beta-amyloid peptide (Aβ13-23) was chosen as the amyloid protein Aβ40 fragment model. Analysis of 1H NMR spectra revealed that the interaction exists for both types of molecules. It was also suggested the possible location of gadolinium (III) ion in the studied molecules.

Keywords

• NMR spectroscopy
• Amyloid peptide (Aβ13-23)
• tetrapeptide (SFVG)
• Gadolinium (III) chloride