Characterization and purification of cytosolic and membrane-bound protease(s) in adults of Haemonchus contortus

The activity of protease(s) was observed separately in cytosolic and membrane-bound protease(s) from male and female Hae monchus contortus (Nematoda: Trichostrongylidae). Different fractions showed optimum protease activity at 37 degrees C, pH 8.5 and 8.0 mg casein concentration. The female fractions had a particularly high activity of protease(s) in comparison with the male fractions, especially of membrane-bound enzymes in the anterior half. Inhibition, activation studies revealed the presence of four kinds of protease(s) in cytosolic and membrane-bound fractions. Protease(s) in different fractions are purified to a greater extent by higher concentrations of saturated ammonium sulphate solution, i.e. ranging from 50 to 65%. The purification study revealed the presence of multiple forms of protease(s) in cytosolic and membrane-bound extracts of H. contortus.