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 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 [3H-methyl]-thymidine incorporation and did not inhibit the activity of HIV-1 reverse transcriptase. The lectin had no antifungal activity.