About the Lectin

Seeds of black locust contains two lectins of similar reactivity, each of which is a homotetramer of 34 kDa or 29 kDa subunits that differ primarily in their number and occupancy of glycosylation sites ¹ . Other workers have reported more complex subunit structures, possibly due to variation in the source and homogeniety of seeds ^1-3 . The lectins bind to immobilized fetuin, but the carbohydrate specificity is complex since none of the simple mono- and disaccharides tested are inhibitors of agglutination ⁴ . Neuraminidase treated cells react more strongly than untreated human erythrocytes. Hemagglutination has been reported at concentrations of 10&#956g/ml, however the material supplied by EY Laboratories reacts with neuraminidase treated cells at a concentration of approximately 100&#956g/ml. A sialoglycoprotein found in the urine of pregnant women is a strong inhibitor of agglutination ⁵ . A glycopeptide is released after treatment with Pronase and trypsin, which is responsible for the agglutination activity of the lectin. A lectin has also been isolated from the bark of the black locust tree ⁶ . The seed and bark lectins are the products of two and three distinct genes, respectively ¹ . RPA is a potent human T-cell activator ⁷ , and also selectively agglutinates Lancefield group C Streptococci ⁸ .

REFERENCES

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8. Kellens, J.T. (1994) J. Med. Microbiol. 41 : 14-19.