Partial characterization of hemagglutinin activity of the marine sponge Anthosigmella varians

The marine sponge Anthosigmella varians contains proteins that agglutinate human erythrocytes irrespective of their ABO group antigens. The hemagglutination reaction depends on divalent cations and is not inhibited by L-arabinose, D-xylose, L-rhamnose, D-galactose, D-glucose, L and D-fucose, N-acetyl-D-galac-tosamine, N-acetyl-D-glucosamine, methyl-alpha-D-mannopiranoside, D-cellobiose, lactose, maltose, melibiose nor raffinose (33 mM each). A partial purification of the hemagglutinins with 31-fold increase in SA and 80% recovery of activity was obtained after gel filtration and ion-exchange gradient elution chromatography. Hemadsorption experiments carried out with the semipurified fraction using glutaraldehyde-fixed human erythrocytes suggest that proteins with molecular weight of 90 and 34 kDa participate in this reaction.