HIGH-LEVEL EXPRESSION AND SECRETION OF STREPTOKINASE IN ESCHERICHIA-COLI

The high-level expression plasmid for streptokinase, pSK100, has been constructed. It contains a tac promoter, an ompA signal sequence, a st reptokinase structural gene(skc) and a rrnBT1T2 transcription terminat or. E. coli JM109 carrying pSK100 produced about 5,000IU of streptokin ase per 1 mi of LB-ampicillin media. About 95% of the expressed strept okinase was secreted into the periplasmic and extracellular fractions. The recombinant streptokinase in high yield and purity may be a poten tial alternative source for the therapeutic agent.