Expression Purification And Identification Of The Initial Function Of Recombinat Staphylokinase In E.coli Expression System

Objective: To construct the expression vector of humanstaphylokinase (SAK) gene, express SAK protein in E.coli, purifyrecombinant SAK protein and to verify its bioactivity.Methods: On the basis of bioinformatics, gene sequence was analyzedand optimized, SAK plasmid was constructed by gene synthesize methodsand the protein was expressed by BL21strain. The recombinant protein waspurified by ion exchange coloum (DEAE) and size exclusionchromatography (Superdex75). Soluble fibrin plate method was used tocharacterize its fibrinolytic activity.Results: The recombinant SAK was highly expressed in solublesupernatant by E coli system. The recombinant protein with95%puritywas obtained by using of DEAE and Superdex75. Experiments in vitrorevealed that the fibrinolytic activity of SAK was approximately equal tothat of urokinase.Conclusion:The recombinant SAK with high fibrinolytic activity canbe highly expressed in E coli system by utilizing sequence optimizing and gene synthesize.