KINETIC STUDIES ON ACID PHOSPHATASE IN TRIBOLIUM CONFUSUM DUVAL

Abstract

The biochemical characteristics of acid phosphomonoesterase in Tribolium confusum homogenate have been determined. Zero-order reaction occurs for 30 minutes, with 10−3 M final concentration of phenyl phosphate at an optimum pH of 6.4. Michaelis constant (Km) under the optimal conditions is 6.34 × 10−3 M. Maximum enzyme activity is obtained at 40 °C, and the activation energy (ΔE) is 13,000 cal/mole, within the limits of optimum temperature. Inorganic phosphate inhibits competitively and Kivalue is 3.45 × 10−3 M. Partial inhibition by fluoride is shown. Apparent effect of metallic ions also has been demonstrated.Comparison of these results with those reported in the literature for several other species of insects, as well as with those in certain mammalian systems, has been discussed.