Cathepsins (CTS) are proteases that degrade proteins. They are present in all animals and other organisms. These proteases are of three types: cysteine proteases, aspartyl protease and serine proteases. Cathepsins are produced as inactive proenzyme precursors that are subsequently activated in lysosomes. Biovision's EZAct? Procathepsin Activation Buffer is a ready-to-use buffer for generation of active cysteine/aspartyl Cathepsins by auto-activation of the Procathepsins.