Sambucus nigra lectin (EBL II/SNA II) isaffinity purified from elderberry bark. This lectin is a glycoprotein containing 7.8% carbohydrate and is not blood group specific. It is composed of two subunits and has a molecular weight of 140,000. EBL II has a specificity for carbohydrates containing terminal N-acetylgalactosamine and galactose residues.
The blood group A-active trisaccharide containing L-fucosyl group linked α1-2 to galactose is 10-fold lesser as an inhibitor than the parent oligosaccharide (GalNAc α1-3Gal), which suggests steric hindrance to binding by the α-L-fucosyl group and explains the failure of the lectin to exhibit blood group A specificity.
EBL II induces caspase-dependent apoptosis at low concentrations (nM) order, leading to typical symptoms of cell death in sensitive cells. This effect seems dependent on the carbohydrate binding B-chain.
Colloidal gold can be used to visualize localization of specific saccharide moieties and examine the distribution of plasma membrane glycoproteins based on the binding pattern of Sambucus nigra Lectin (SNA/EBL II). Colloidal gold labeled lectins can be viewed via electron microscopy.