Lectins of plants can be used in the analysis of glycoconjugates present in normal and tumoral cells. They are a powerful tool to establish the relationship between glycan structure and cell-specific functions. These proteins are widespread in nature and most of them have been isolated and featured from Labiatae, Gramineae and Fabaceae families, the last one signalled their ability to recognize many antigens and the most studied in this field. Preliminary experiments have shown lectin activity in crude extracts from seeds of Calopogonium galactoides (subtribe Glycininae, family Fabaceae). Therefore this work focused on molecular identification of a novel lectin from Calopogonium galactoides which recognizes mannose. Primers were designed in order to get the gene amplification from DNA and mRNA extracts of seeds; the design was performed by comparing sequences of nearby subtribes lectins (Glycininae and Diocleinae), taking into account the affinity towards mannose based on the sequences of Vicia faba (LEC2). PCR amplification showed two bands around to 1347 and 672 bp; primers designed towards sequences that recognize galactose were not such successful. PCR products could generate 29-31 kDa protein. At present, we are working on expression of the lectin in order to get knowledge of new tools that can be used to recognize tumoral markers and our next aim is to carry out structural studies on new lectin. To date this field is unexplored.
[1] Alvarado R. C., 2012, Purification and preliminary characterization of the lectin present in Calopogonium galactoides as possible cytotoxic agent for tumor lines, Bcs final work, unpublished.
[2] Hamelryck, T. W. 1998, Structural Features of the Legume Lectins, MINIREVIEW, Trends in Glycoscience and Glycotechnology Vol.10 No.55 (September) pp. 349-360
[3] Loris R, et al,1998, Legume lectin structure review. Biochim. Biophys. Acta.;1383:9–36.
Key words: Calopogonium lectin, glycoconjugate, carbohydrates, tumoral marker, Recombinant lectin
