Purification and Partial Characterization of a Haemagglutinin from Ulva fasciata

A novel haemagglutinin has been detected from Ulva fasciata, a green marine alga. By a combination of ammonium sulphate precipitation and ion-exchange chromatography on DEAE-cellulose column, we have purified a haemagglutinin and designated it as UFH (Ulva fasciata haemagglutinin). It agglutinated native human blood cells without any blood group specificity. Under reducing and non-reducing conditions, this agglutinin was isolated as a monomeric protein with a relatively low molecular weight of 14.5 kDa. The activity of UFH was thermo-stable, expressing functionality at 40–100°C and not inhibited by the inclusion of divalent cations nor pH changes, being stable at pH values 6.0–10.5. None of the tested monosaccharides and glycoproteins inhibited agglutination by UFH. The observations indicate that the properties of UFH are consistent with its recognition as a haemagglutinin isolated from marine algae. The pH stability, highlevel activity and thermo-stability thus support its candidature for future applicability in lectin research, glycobiology and biomedical applications.