Production of recombinant streptokinase in E. coli and reactivity with immunized mice.

Streptokinase (SK) is a potent plasminogen activator with widespread clinical use as a thrombolytic agent. In this study, we produce high level expression of recombinant streptokinase in E. coli by expression vector pET32a. Genomic DNA of streptokinase gene (SKC) was extracted, then amplified by polymerase chain reaction (PCR) method and sub-cloned to prokaryotic expression vector pET32a. Escherichia coli BL21 (DE3) pLysS were transformed with pET32a-skc and gene expression was induced by IPTG. The expressed protein was purified by affinity chromatography by Ni-NTA resin. High concentration of the recombinant protein obtained from the single-step purification by affinity-chromatography (Ni-NTA). The yield of recombinant streptokinase was nearly 470 mg L(-1) of initial culture. Our data showed that production of recombinant streptokinase improved by pET32a in Escherichia coli.