Survey Activity and stability of aldehyde oxidase in the Water-Miscible Organic Solvents

In this study, the catalytic activity of aldehyde oxidase in water miscible organic solvents examined for the first time This enzyme was purified from rabbit liver, and the activity in the absence / presence of none organic- aqueous mixture was determined. Decreased enzyme activity in the presence of none organic solvents. However, in some cases, the residual activity remained almost unchanged throughout the incubation of enzyme at 25°C,35°C,45°C, for 24 h. Thermal stability parameters (half-life, inactivation constant, and activation energies for enzyme inactivation), thermodynamic constants (ΔH*, ΔS*, and ΔG*) and the kinetic parameters (Km and Vmax), were determined in organic solvents containing buffer solution. The enzyme was stable even in the presence of methanol, 2-propanol ,acetonitrile .The effects of pH and temperature on the enzyme activity were also investigated .Considering potential advantages of doing reactions in the presence of organic solvents, these results could be of value. The enzyme showed different behavior in the reaction solutions making it difficult to formulate results in a single comprehensive model. The results indicated that binding and cleavage of the substrate are influenced in the presence of organic solvents.

Keywords:

Aldehyde oxidase , Thermal stability , Kinetic constants