Cicer arietinum lectin or agglutinin (CAL/CPA) is isolated from chickpeas. CAL is identified as a homodimer composed of two subunits confirmed by SDS-PAGE and has the molecular weight of 43,000. This lectin is a glycoprotein that contains 4.5% neutral sugars and is basic in nature (pI: 9.0).

It’s haemagglutination activity is inhibited by fetuin and desialylated fetuin with a carbohydrate specificity for fetuin and p-Nitrophenyl N-acetyl-beta-D-galactoside. CAL possess complex-sugar specificity for N-glycans and N-acetyl-D-galactosamine, and elutes with acetyl-D-galactosamine. Although neither human or rabbit erythrocytes are agglutinated by this lectin, pronase-treated rabbit and human erythrocytes have been successfully agglutinated. None of the sugars, such as glucose, mannose or galactose, nor their derivatives, disaccharides, trisaccharides and tetrasaccharides have any effect on the agglutination of this lectin.