Efficient expression of several recombinant proteins by pSUMO expression vector

The objective of the paper is to utilize pSUMO expression vector to efficiently express several recombinant proteins in E.coli system,including mouse fibroblast growth factor(FGF)-21,human FGF-21 and human interleukin(IL)-1β,in comparison with pET-30a(+) and pTYB11 expression systems.The genes of mouse FGF-21,human FGF-21 and human interleukin(IL)-1β were subcloned into the pSUMO expression vector.The recombinant plasmids were transformed into Escherichia coli Rosetta(DE3) and the expressed recombinant proteins were purified by His binding column.The purified recombinant proteins were dialyzed against PBS.The fusion proteins could be efficiently cleaved by SUMO protease-Ⅰto obtain pure and active recombinant proteins.Expression level of these genes was very low in pET-30a(+) and pTYB11 expression systems and could not be detected by Coomassie blue staining.However,all these cDNAs were expressed in soluble form and the recombinant proteins accounted for 30%-50% of total bacterial proteins in the SUMO expression system.The pSUMO expression vector can efficiently express soluble recombinant proteins.