An α-D-Galactopyranosyl-Containing Glycoprotein from Ehrlich Ascites Tumor Cell Plasma Membranes

Abstract

The observation from an earlier study that a saline extract of Bandeiraea simplicifolia seeds agglutinated a murine maramary-adenocarcinoma ascites cell subline suggests the presence of terminal α-D-galactopyranosyl residues on the cell surface. The agglutination reaction was inhibited by D-galactose, N -acetyl- D -galactosamine, and melibiose. Recently, five isolectins have been purified from B. simplicifolia seeds. In an experiment described in the chapter, the use of B4-isolectin enzyme revealed the presence of terminal α-D-galactopyranosyl residues on the surface of another murine mammary tumor, the Ehrlich ascites tumor cell. The isolectin mixture and preparative gel electrophoresis were used in the presence of sodium dodecyl sulfate (SDS-PAGE) to purify an α-D-galactosyl-containing glycoprotein from Ehrlich cell plasma membranes. B 4 -Isolectin conjugated to horse spleen ferritin was also used to demonstrate the presence of α-D-galactosyl residues on the Ehrlich cell surface. The presence of terminal α-D-galactosyl residue in glycoproteins resulted in isolation and characterization of a glycoprotein with α-galactosyl units from Ehrlich cell plasma membrane.