Effects of Alcohol on Chymotrypsin Inhibitor 2

Abstract

The folded native structure of a protein is highly sensitive towards the nature of solvent under specific environmental conditions. With the change of solvent’s physicochemical properties protein’s native structure can be disrupted. Among several organic solvents water-alcohol binary mixtures have been of interest among biologists, physicists, chemists and engineers due to their relevance in many areas such as the pharmaceutical industry, biofuels, and protein aggregation. Further, monohydric alcohols are widely used as cosolvents in biology due to their unusual behavior at various concentrations. In this meeting, I shall discuss the behavior of a small enzymatic protein, Chymotrypsin Inhibitor 2 (CI2) in various monohydric alcohol-water binary mixtures at several alcohol concentrations under thermal stress.3,4 In our work an emphasis has been taken to identify the origin of the protein’s conformational disorder in water-alcohol mixed solutions. 5 Our study in general reveals that the presence of alcohols accelerates the unfolding process of CI2 which further depends on the concentration and nature of the alcohols used. The fluorinated alcohol is noted to speed up the unfolding time scale at low concentration whereas the reverse trend is noted at higher concentration. Our study further reports that the alcohols have mixed direct and indirect effects on the denaturing process.