Roles of the structural units, glycotopes / mammalian N-glycans for Con A-glycan interactions, their codes, and their recognition factors

Abstract

The binding property of Con A has been studied intensively and applied widely to glycoconjugates / glycobiology for over 80 years. However, its role and functional relationship of Con A with these mammalian structural units, glycotopes, N-glycan chains, as well as their polyvalent forms in Nglycoproteins involved in the Con A-glycan interactions have not been all de ned and organzied. In this study, the recognition factors involved in these inteactions were azalyzed by our well developed methodthe enzyme linked lectinosorbent (ELLSA) and inhibition assay. Based on all data obtained, it is concluded that Con A, as previous report, has a relatively broad and wide recognition ability with the Manα1→ and Glcα1→ related glycans. In addition to it reacted strongly with yeast mannan and glycogens, it also bound well with a large number of mammalian N-glycans, including the N-glycans of rat sublingual gp (RSL), human Tamm-Horsfall glycoprotein (THGP), thyroglobin and lactosferrin. The recognition speci city of Con A towards ligands, expressed by Molar Relative Potency (Molar R.P.), in a decreasing order is as follows: a1→3, a1→6 Mannopentaose (M 5 ) and Biantennary N-linked core pentasaccharide (M Di ) ≥ a1→3, a1→6 Mannotriose (M 3 ) > Mana1→3Man (α1→3Mannobiose), Mana1→2Man (α1→2Mannobiose), Mana1→6Man (α1→6Mannobiose), Mana1→4Man (α1→4Mannobiose) > GlcNAcb1→2Man (b1→2 N-Acetyl glucosamine-mannose) > Mana1→/Glcα1→ > Man > Glc, while Gal / GalNAc were inactive. Furthermore, the Man related code system, in this study, is proposed to express by both numbers of Man and GlcNAcb1→ branches (M 3 to M 9 / M Mono to Penta etc. ) and a table of three Mana1→ and Glca1→ related biomasses of six recognition factors involved in the Con A-glycan interactions has also been demonstrated. These themes should be one of the most valuable advances since 1980s.