An antifungal protein from flageolet beans

Abstract A protein with antifungal and hemagglutinating activities was isolated from dried flageolet beans ( Phaseolus vulgaris cv. ‘Flageolet Bean’). The protein was unadsorbed on DEAE-cellulose but adsorbed on Affi-gel blue gel and CM-cellulose. The protein demonstrated antifungal activity against Mycophaerella arachidicola with an IC 50 of 9.8 μM, but was inactive toward Fusarium oxysporum and Botrytis cinerea . Its hemagglutinating activity could not be inhibited by a variety of the sugars tested. The activity was stable up to 60 °C. At 70 °C, 75% of the hemagglutinating activity remained while no activity was discernible at and above 100 °C. The hemagglutinating activity was stable in the presence of a variety of monovalent, divalent and trivalent chlorides, and also when the ambient pH changed from 3 to 12. It did not exert any mitogenic activity on mouse splenocytes in vitro. Neither did it inhibit HIV-1 reverse transcriptase. It inhibited [ 3 H-methyl]-thymidine incorporation into leukemia L1210 cells with an IC 50 of about 4 μM.