ENHANCED PRODUCTION AND SECRETION OF STREPTOKINASE INTO EXTRACELLULARMEDIUM IN ESCHERICHIA-COLI BY REMOVAL OF 13 N-TERMINAL AMINO-ACIDS

The production and secretion of streptokinase using OmpA signal sequen ce 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 ex tracellular medium was two times higher than that of wild-type strepto kinase. About 4500 IU of SK Delta N13 protein per 1 mi LB-ampicillin m edium was secreted into extracellular medium at 12 hours after inducti on. Fully active and enhanced extracellular preparation of the mutant streptokinase may be a potential alternative source for the simple dow nstream processing.