About the Lectin

The role of various bacteria species in the nitrogen fixing, symbiotic relationship with the roots of legumes has been well documented. White clover, Trifolium repens, has a specific symbiosis with the soil bacterium Rhizobium trifolii. A protein, trifoliin, found in white clover seeds and roots has been purified and found to specifically agglutinate R. trifolii ¹ . Biochemical studies indicate that the lectin acts as a bridge between the root hair and the bacterium. The sugar is specific for 2-deoxyglucose. This sugar can selectively leach the lectin from intact root hairs as well as prevent lectin mediated agglutination of the bacteria. Bacterial strains that are not able to infect the root are also not reactive with the lectin. This proves the specificity of the interaction ² . Trifoliin has been used recently to study development of the capsular polysaccharide of R. trifolii and its affect on bacterial binding to clover roots ³ .

REFERENCES

1. Dazzo, F. B., et al. (1978) Biochim. Biophys. Acta. 539 : 276-286.
2. Dazzo, F. B. and Hubbell, D. H. (1975) Applied Microbiology. 30 : 1017-1033.
3. Sherwood, J. E., et al. (1984) J. Bacteriology. 159 : 145-152.