The effect of triethylammonium ‎propionate ionic liquid on the ‎catalytic efficiency and ‎thermostability of urate oxidase

Ionic liquids (ILs) are salts that can affect the structure, stability, and function of proteins. Researchers have recently been interested in finding ionic liquids that increase the stability, activity and solubility of enzymes. In this study, efforts are made to investigate the effect of triethylammonium propionate (TEAP) on the function of urate oxidase (UOX). We treated the enzyme in different concentrations of TEAP. The volume percentages of TEAP in the solvent phase are 0.5%, 1%, 2%, 5%, 10% and 15%. The results  indicate that TEAP has a concentration-dependent effect on the activity of UOX enzyme. The use of 1% TEAP ionic liquid increased the enzymatic activity in comparison to untreated enzyme. We concluded that  this ionic liquide was able to alter the structure of the uricase in a way that increased the activity and improve its catalytic efficiency of the enzyme. Also the thermodynamic prameters such as ΔG#, ΔH#, and ΔS# values indicate that the use of 1% of triethylammonium propionate increases the thermostability of uricase and reduces the conformational changes of this enzyme during thermal inactivation process.