A SURFACE-PLASMON RESONANCE ASSAY FOR THE BINDING OF AMARANTHUS-HYPOCHONDRIACUS VAR. MEXICO LECTIN TO GLYCOPROTEIN

We have used the analytical system based on surface plasmon resonance to monitor the interaction between Amaranthus hypochondriacus var. Mex ico lectin and four different fetuins; fetuin, asialofetuin, agalactof etuin, and agalactosaminofetuin. Agalactofetuin and agalactosaminofetu in were prepared by enzymic digestion of asialofetuin using jack bean beta-galactosidase or endo-alpha-N-acetylgalactosaminidase from Diploc occus pneumoniae. Ligands were immobilized onto a sensor surface via a mide linkages. The lectin interacted most strongly with asialofetuin, but not with agalactosaminofetuin. The binding of the lectin to asialo fetuin was inhibited by N-acetylgalactosamine or Gal beta 1-->3GalNAc in a dose-dependent manner.