Purification and preliminary characterization of a protease from the excretion-secretion products of Trichinella spiralis muscle-stage larvae.

A protease from excretion-secretion products of Trichinella spiralis muscle-stage larvae was purified by continuous elution electrophoresis. The state of purification was analyzed electrophoretically using one- and two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis. The purified enzyme was shown to be a single polypeptide with an estimated molecular mass of 35 kDa and isoelectric point of 6.2. Following purification, the enzyme activity was measured by hydrolysis of gelatin, azocoll, azoalbumin, azocasein and collagen as substrates. Maximal azocollytic activity was at pH 5 and a temperature of 37 degrees C. Finally, the proteolytic activity was partially inhibited by N-alpha-p-tosyl-lysine chloromethyl ketone, chymostatin and E-64.