Proteolytic Activity In Adult Haemonchus Contortos

Abstract

Proteolytic activity of the JQ.qOOxgsupernate of homegenates ef adult Haemonchus contortus has been studied with respect to substrates susceptible to its proteolytic activity, and the effects of factors such as temperature, pH, substrate concentration, extract concentration, dibasic metal ions, detergents, heat and some specific inhibitors of proteolytic activity. The supernate had two pH optima, 5.6 with haemoglobii as substrate, and 7.8 using L-alanyl - p-nitroanilide. It showed optimum activity at 36°C, was heat labile and in general was not significantly affected by the presence of metal ions in the hydrolysis of haemoglobin and L-alanyl p-nitroanilide. In screening for substrates susceptible to its hydrolytic action the most suitable were found to be those p-nitroanilides and jp-naphthylamides which have a single amino acid group (small R-group), unprotected at the free functional group end. The kinetic studies indicated that haemoglobin was more rfeadily hydrolysed than the p-nitroanilides and p-naphthylamides.