both enzymes are insensitive to inhibitor-1 and -2 and stimulation of enzymatic activity ( 2.5-fold with pp-x and 6.5-fold with pp-y ) can be accomplished by ethanol treatment of the native enzymes , or freeze-thawing in the presence of 1.7 % ( v/v ) 2-mercaptoethanol .
C0001962
ethanol
C0025402
mercaptoethanol