The solubilization of lipase in reverse micelle-containing organic solutions was investigated. Reverse micelles are nanometer-scale droplets of aqueous solution stabilized in an organic solution by a surfactant layer at the droplet interface. Previous workers have demonstrated the possibility to solubilize proteins, which are usually insoluble in organic solvent, in reverse micelle-containing organic solvents without denaturation. Elucidation of the parameters that control the solubilization phenomenon, and the fundamental interactions which govern it, was the primary focus of this study.
A cationic surfactant, cetyltrimethyl ammonium bromide(CTAB), was employed in most experiments. Two lipases were used and the experimental results were interpreted in terms of two qualitative models, kinetic and thermodynamic.
When the net charge of the protein is of opposite polarity to that of the surfactant head group, a favorable interaction was predicted. For the cationic surfactant used, solubilization was not accomplished when pH
