Characterization of the Esterases From Electric Tissue of Electrophorus by Starch-Gel Electrophoresis

The water-soluble esterases of a microsome-free supernatant of the electric tissue of Electrophorus electricus were separated by vertical-zone electrophoresis in starch gel. Specific and nonspecific substrates and inhibitors were used in conjunction with histochemical techniques to identify the enzymes. Acetylcholinesterase was present in the form of four bands of activity, the electrophoretic mobility of which was suggestive of aggregated forms of the enzyme. Pseudocholinesterase was detected as two weak bands of activity. A third esterase was identified as a nonspecific carboxylesterase and shown to be a sialoprotein.