Purification and Characterization of a Lectin from the Indian Cultivar of French Bean Seeds

A lectin specific for glucuronic acid and galacturonic acid has been isolated from seeds of the French bean Phaseolus vulgaris using a procedure that involved affinity chromatography on Affi-gel blue gel, fast protein liquid chromatography (FPLC)-ion exchange chromatography on Mono S, and FPLC-gel filtration on Superdex 200. The lectin was comprised of two 32-kDa subunits with substantial N-terminal sequence similarity to other Phaseolus lectins. The hemagglutinating activity of the lectin was stable within the pH range of 1-13 and the temperature range of 10-60 degrees C. The lectin neither exhibited any antiproliferative activity against tumor cells nor stimulated nitric oxide production by murine peritoneal macrophages at doses as high as 1mM, The lectin failed to evoke any mitogenic response from murine splenocytes as measured by [H-3-methyl]-thymidine incorporation and did not inhibit the activity of HIV-1 reverse transcriptase. The lectin had no antifungal activity.