Affinity purified Hippeastrum hybrid lectin (HHL) is consists of four subunits of identical size. It binds only to (α-1,3) and (α-1,6) linked mannosyl units of α-mannose residues. HHL reacts not only with terminal but also with internal α-D-mannosyl residues. Lectin appears to possess extended binding sites complementary to at least three 1,6-linked α-mannosyl. HHL also binds to some yeast galactomannans.
Alkaline phosphatase (AP) is conjugated to Hippeastrum hybrid Lectin (HHL) to show the binding of HHL in many applications including Western blotting and ELISA. Alkaline phosphatase is a large protein (140 kDa) that catalyzes the hydrolysis of phosphate groups from a substrate resulting in a colored or fluorescent product. The optimal enzymatic activity of this protein is between pH 8 and 10, and its reaction rate remains linear, improving sensitivity over time.