The oligosaccharides in a recombinant hepatitis B virus surface antigen (HBsAg) carrying the pre-S2 region derived from yeast

AbstractThe N- and O-linked oligosaccharides in a yeast-derived HBsAg M protein (pre-S2 + S) were analyzed. Two major structures of the N-linked oligosaccharides bound to residue Asn4 were determined to be high-mannose type oligosaccharides. Man7GlcNAc2 and Man8GlcNAc2, by two-dimensional sugar mapping of the corresponding pyridylamino oligosaccharides. Peptide mapping of the M protein, sequence analysis of the glycopeptides after β-elimination under reducing conditions and sugar-composition analysis revealed that the O-linked oligosaccharides were composed solely or mannose and bound to residue Ser5, Thr6, Thr7, Ser27, Ser28, Ser29 and Thr31 in the pre-S2 region