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). Cy5, when bound to Griffonia simplicifolia Lectin (GSL II), can show the binding pattern of this lectin in cellular imaging and flow cytometry. The excitation wavelength required for Cy5 to fluoresce is high enough to avoid overlap with most other fluorochromes, making it useful for dual-labeling experiments. Because of this high excitation, there is typically less background from autofluorescence of biological specimens.