GSL II is affinity purified tetramer that contains a single type of 30 kDa subunit. It has insecticidal structure/function, the first GlcNAc binding legume lectin proven to have insecticidal activity.This lectin has a carbohydrate specificity for Î±Gal and Î±GalNAc and elutes with galactose or N-acetylgalactosamine. Increasing the number of N-acetylglucosamine residues beyond two does not improve affinity. It has been reported to be unique in its ability to recognize exclusively Î±- or Î²-linked N-acetylglucosamine residues on the nonreducing terminal oligosaccharides. This lectin shows specificity for blood group A(-SA) greater than blood group B(-SA). 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 Griffonia simplicifolia Lectin (GSL II). Colloidal gold labeled lectins can be viewed via electron microscopy.