EFFECTS OF PHASEOLLIN ON MEMBRANE LEAKAGE IN RED BEET VACUOLES AND TONOPLAST VESICLES

Acting in a manner similar to that of glyceollins I and III, phaseolli n appears to inhibit proton transport in red beet tonoplast vesicles. In the presence of 80 mu M phaseollin, proton transport in tonoplast v esicles was inhibited by >90%. This inhibition appears to be due to in creased conductance across the tonoplast membrane and not to inhibitio n of tonoplast ATPase. Moreover, phaseollin was shown to cause molecul es, e.g. beta-anthocyanidin, to leak across the vacuolar membrane.