Protease from germinating moth bean seeds

The protease activity in the crude extracts of germinating moth bean (Vigna aconitifolia Jacq.) seeds was investigated. The activity was measured at different pH upto 48 hours of germination. The maximum protease activity was found in 12 hours imbibed seeds and it declined up to 48 hours of germination. The protease activity was enhanced by cysteine, mercaptoethanol, EDTA and thiourea. Increase in activity with these thiol specific activators suggested that this protease possessed cysteine at its active site or near to it. Enzyme inhibition with iodoacetic acid also supported this phenomenon. Enzyme was also inhibited with bivalent cations, viz. Zn²⁺,Cu²⁺,Mg²⁺ and Ca²⁺. This inhibition suggested that enzyme does not belong to metalloprotease class and did not require bivalent cations for the degradation of storage protein.