13C-n.m.r.-spectral study of the binding of Gd3+ to glycophorin

✍ Scribed by Marsha E. Daman; Kilian Dill

• Publisher: Elsevier Science
• Year: 1983
• Tongue: English
• Weight: 745 KB
• Volume: 111
• Category: Article
• ISSN: 0008-6215
• DOI: 10.1016/0008-6215(83)88306-2

✦ Synopsis

Natural-abundance, 13C-n.m.r. spectroscopy was used to study the binding of Gd3 + to glycophorin, and also to the tetrasaccharides isolated from glycophorin after treatment of the glycoprotein with NaOH-NaBH,. Gd3+ binds to the tetrasaccharide (both in the isolated, reduced form and when still attached to the native glycoprotein), and, especially, to the u-NeuAc residues. In order to cause severe linebroadening of the 13C resonances of a-NeuAc, the ratios of the sl-NeuAc residues of glycophorin, and of the isolated, reduced tetrasaccharide, to Gd3+ were much higher than that needed for causing similar broadening for 2-O-methyl-a-NeuAc-Gd3+ solutions. These results indicate that the other carbohydrate residues of the tetrasaccharide may be involved in the binding of Gd3+, producing a stronger metal-ionbinding effect. *To whom requests for reprints should be addressed. **Hexein, the anomeric designator is used in relation to the D configuration of C-8.