Electron spin resonance study of Gd(III) ions bound to iron binding sites in chicken ovotransferrin

Abstract

Electron spin resonance (ESR) of Gd(III) ions bound to the two iron binding sites (amino and carboxy sites) in chicken ovotransferrin was studied to investigate the differences between them. From the analysis of the ESR spectrum and its concentration dependence on Gd(III), it is concluded that the symmetry of the ligand field is almost the same for both binding sites and that the magnitude of the carboxy site is larger than that of the amino site.