Vicia villosa lectin (VVL, VVA), Fluorescein labeled

Vicia Villosa Lectin (VVL, VVA), Fluorescein, 2 mg, is a conjugated form of VVL. The VVL lectin family of tetrameric glycoproteins comprises combinations of A and B subunits similar in structure to PHA and GSL I. The dominant isolectins in this preparation appear to be B subunit-rich. VVL preferentially recognizes alpha- or beta-linked terminal N-acetylgalactosamine, especially a single alpha-N-acetylgalactosamine residue linked to serine or threonine in a polypeptide (the Tn antigen), with evidence suggesting it may require specific amino acid sequences at the receptor site of glycosylation. The disaccharide galactosyl (alpha-1,3) N-acetylgalactosamine is a potent inhibitor of this lectin. Fluorescein-labeled VVL 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.