Phaseolus limensis agglutinin (LBA) is isolated from lima bean seeds and purified by affinity chromatography. LBA is composed of 30,000 Da subunits, of which two are joined by a disulfide bond. Each subunit contains a cysteine residue which is required for both it’s carbohydrate- and metal-ion-binding activities. It has a carbohydrate specificity of terminal GalNAcα(1,3)Gal that elutes with N-acetylgalactosamine. LBA agglutinates blood group A erythrocytes.
Horseradish peroxidase (HRP) is a 40 kDa protein that catalyzes the oxidation of substrates by hydrogen peroxide, resulting in a colored or fluorescent product or release of light as a byproduct of the reaction. It is most commonly used for blotting, immunoassays and immunohistochemistry methods. Phaseolus limensis Lectin (LBA) is conjugated to HRP at an appropriate ratio to provide optimal staining characteristics.