Tumor antigen occurs in N-glycan of royal jelly glycoproteins: Honeybee cells synthesize T-antigen unit in N-glycan moiety

Abstract

In our previous paper (Kimura, Y., et al., Biosci. Biotechnol. Biochem., 67, 1852-1856, 2003), we found that a complex type N-glycans containing β1-3 galactose residue occurs on royal jelly glycoproteins. During structural analysis of minor components of royal jelly N-glycans, we found complex type N-glycans bearing both galactose and N-acetylgalactosamine residues. Detailed structural analysis of pyridylaminated oligosaccharide revealed that the newly found N-glycan had a complex type structure harboring a tumor marker (T-antigen) unit: Galβ1-3GalNAcβ1-4GlcNAcβ1- 2Manα1-6 (Galβ1-3GalNAcβ1-4GlcNAcβ1-2Manα1-3) Manα1-4GlcNAcβ1-4GlcNAc. To our knowledge, this may be the first report of the presence of the T-antigen unit in the N-glycan moiety of eucaryotic glycoproteins.