Glycopeptides from murine teratocarcinoma cells: structure of the determinants recognised by Griffonia simplicifolia agglutinin I and by sera from patients with ovarian germ cell tumors.

High-molecular-weight glycopeptides synthesised by teratocarcinoma OTT6050 bear the binding site for Griffonia simplicifolia agglutinin I and are recognised by antibodies in the sera of patients with ovarian germ cell tumors. Digestion of the glycopeptides with endo-beta-D-galactosidase C abolished the lectin binding activity and the antigenic activity. Since the product of the enzymic digestion is alpha-D-Gal-(1----3)-D-Gal, it is concluded that the disaccharide structure is involved in the lectin binding site and the antigenic site.