Characteristics and Kinetics of Kallikrein Enzyme from Arabian Camel Pancreas

The characteristics and kinetics of kallikrein enzyme from camel was investigated in this study. The enzyme activity was inhibited by urea, phenylmethyl sulfonyl fluoride (PMSF), leupeptin, cations and aprotinin. The enzyme activity was optimum at pH 10.0 and was stimulated by different concentrations of deoxycholate. The enzyme was shown to be heat labile enzyme. Its activity was not affected by heating of the enzyme at 45°C for 30 min. However, this kallikrein retained 75% of its activity by its heating at 50°C for 30 min. Latter temperatures above 50°C caused partial degradation of the enzyme reaching 78.5% at 70°C. The rate of thermal inactivation of the enzyme at 50°C, 60°C, 70°C showed first order kinetics with constant rates of about 8.98 X 10-3, 3.22 X 10-2, 9.60 X 10-2 / min. respectively. The Michalis – Menten constant Km and Vmax were showed to be 40.0 μmole/min and 8.53 μmole/min. respectively