Renaturation of recombinant secretory leukocyte protease inhibitor: Aspects of disulfide bond formation kinetics

Summary Therapeutic proteins produced in procaryotic hosts often contain disulfide bonds, which must be fully formed to satisfy United States Food and Drug Administration regulations. Native secretory leukocyte protease inhibitor (SLPI), a possible emphysema therapeutic agent, contains many disulfide bonds. However, when SLPI is produced in Escherichia coli by rDNA technology, the disulfide bonds are not formed correctly and must be generated by in vitro renaturation. In this study, the reaction rate parameters were estimated for SLPI renaturation. The apparent activation energy was approximately 5 kcal/mol suggesting that renaturation is a diffusion limited process. Apparent reaction rate orders were not constant, suggesting complex renaturation mechanism(s).Currently at Texas A & M University, College Station, Texas 77843, Department of Chemical Engineering.