Agaricus bisporus agglutinin (ABA) is an affinity-purified tetramer composed of two to four isolectins. ABA has two distinct carbohydrate binding sites, one for galactose-ß-1,3-N-acetylgalactosamine and another for galactose-ß-1,3-N-acetylglucosamine. Agaricus bisporus has an anti-proliferative effect on cancerous cells. ABA can be internalized by clathrin-coated vesicles after binding to surface glycoproteins, thus making ABA an inhibitor of its nuclear import of signal-dependent proteins. Biotin is a small molecule involved in a wide range of metabolic processes. This ligand forms a complex with Avidin and Streptavidin, resulting in the strongest non-covalent protein-ligand interaction known. Biotinylated Agaricus bisporus Lectin (ABA/ABL) has an appropriate amount of biotin bound to provide optimum detection characteristics when using an Avidin-HRP or Streptavidin-HRP conjugate. Biotinylated ABA/ABL allow for more sensitive detection in ELISA and Western-blotting applications.