Anti-carbohydrate precipitins and haemagglutinins in haemolymph from Tridacna maxima (Röding).

Haemolymph from the elongate clam, Tridacna maxima (Röding) readily precipitates with H-blood group substances, pneumococcus type XIV polysaccharide, human milk and salivas, and with a number of polysaccharides which contain the O-SS-D-galactopyranosyl-(1-6)-D-galactose structure. Precipitation has been demonstrated using both gel diffusion and quantitative precipitin methods. T. maxima haemolymph strongly agglutinates human erythrocytes and haemagglutination can be inhibited by the same preparations which precipitate with the clam extract. Precipitins and haemagglutinins are inhibited by N-acetyl-D-galactosamine and by D-galactose residues preferably in ss-linkage. After agar gel immunoelectrophoresis at pH 8.6, T. maxima precipitin arcs are found in the alpha-region. Precipitation and inhibition results suggest that T. maxima extract and purified precipitin, may find widespread application in the study of many biologically important carbohydrates and glycoproteins.