The molecular forms of human α1-acid glycoprotein. Variations in the occurence of bi-, tri-, and tetraantennary N-linked carbohydrate chains
S. D. Shiyan, V. V. Nasonov, N. V. Bovin, L. I. Novikova, V. A. Aleshkin
M. M. Shemyakin Institute of Bioorganic Chemistry, Academy of Sciences of the USSR, Moscow; G. N Gabrichevski Institute of Epidemiology and Microbiology, Moscow
Abstract: α1-Acid glycoprotein isolated from healthy individuals blood was separated on Con A-Sepharose into three fractions: non-bound (AGP-1, 84%, 43.5 kDa), Con A-bound (AGP-2, 14%, 41.3 kDa), and Con A-tightly bound (AGP-3,2%, 39.6 kDa). Amino acid compositions of these fractions were similar but carbohydrate ones differed. HPLC analysis of 7-amino-4-methylcoumarine derivatives of the oligosaccharides in combination -with their sequential exoglycosidase digestion showed that AGP-1, AGP-2, and AGP-3 have the same set of oligosaccharides and differ only by their proposition. A minor quantity of agalacto-oligosaccharides (with a terminal GlcNAc residue) was identified.
Russian Journal of Bioorganic Chemistry 1991, 17 (5):663-670