Enhanced Production and Secretion of Streptokinase into Extracellular Medium in $Escherichia$ $coli$ by Removal of 13 N-terminal Amino Acids

Abstract

The production and secretion of streptokinase using OmpA signal sequence in E. coli was enhanced by removing the 13 N-terminal amino acids (SK Delta N13). The secretion level of SK Delta N13 protein into the extracellular medium was two times higher than that of wild-type streptokinase. About 4500 IU of SK Delta N13 protein per 1 mi LB-ampicillin medium was secreted into extracellular medium at 12 hours after induction. Fully active and enhanced extracellular preparation of the mutant streptokinase may be a potential alternative source for the simple downstream processing.