Galanthus Nivalis Lectin (GNL), Fluorescein, 2 mg, is a conjugated form of GNL. Unlike most mannose-specific lectins, GNL is not a metalloprotein, does not require Ca++ or Mn++ for binding, and will not bind alpha-linked glucose. Instead, binding seems to be preferentially directed toward structures containing (alpha-1,3) mannose residues. Reports indicate that GNL binds rat and mouse IgM but not IgG and that alpha2-macroglobulin is the only protein from human serum to bind GNL. GNL also binds many viral glycoproteins. Fluorescein-labeled Galanthus Nivalis Lectin has an appropriate number of fluorochromes bound to provide the optimum staining characteristics for this lectin and is supplied essentially free of unconjugated fluorochromes. Fluorescein has an excitation maximum of 495 nm and an emission maximum of 515 nm.