To express mouse endostatin by thioredoxin fusion expression system / 第三军医大学学报

ABSTRACT

Objective To explore the best technology to produce recombinant mouse endostatin by thioredoxin fusion expression system.Methods The recombinant plasmid pThioHis-endo was further transformed into different E.coli.,including BL21,JM109,DH5?.After induction with IPTG of different concentration or for different time period,thioredoxin-endo fusion protein was expressed in E.coli.and the product was identified by SDS-PAGE.The recombinant endostatin expression and extraction,wash,degeneration and refolding of inclusion bodies were carried out by the optimized route,and the product was further purified by affinity chromatography through Ni~(+) column and identified by SDS-PAGE.Results No difference of endostatin expression in BL21,JM109,DH5? was found.The optimal concentration of IPTG was 0.9 mmol/L and optimal inductive phase was 5 h.The soluble recombinant endostatin could be obtained by affinity chromatography through Ni~(+) column.Conclusion Soluble endostatin recombinant fusion protein of high purity and yield could be obtained by the optimized technique route.