RESUMO
BACKGROUND AND PURPOSE: Tobacco etch virus (TEV) protease, a 27 KDa protein, consists of the catalytic domain of nuclear inclusion a (NIa) protein produced by Tobacco etch virus. Because of its unique sequence, TEV protease is used for purging fusion tags from proteins. It also has many advantages such as stability and activity in a board range of temperature and pH and overproduction in Escherichia coli and these benefits make this protease valuable. Despite all these benefits, TEV protease has problems like low solubility (less than 1 mg/mL). There are methods for enhancing protein solubility and in this study, the effect of additives during cell lysis was studied. EXPERIMENTAL APPROACH: Eleven different additives that made twelve different lysis buffers were used and their effect on TEV protease solubility analyzed by Plackett-Burman and response surface methodology methods. FINDINGS / RESULTS: Three best effective additives on TEV solubility (L-proline, sodium selenite, and CuCl2) were selected according to software analysis and the best concentration of them was applied to optimize TEV protease solubility. CONCLUSION AND IMPLICATIONS: The obtained results provided the composition of an optimum solvent for obtaining soluble TEV protease.
