[Preparation of rhIL-11 from fusion protein by using enterokinase]

The study was aimed to investigate the technological parameters of rhIL-11 preparation from fusion protein by using enterokinase. Fusion expression vector pET32a/IL-11 was transferred into E.coli BL21 (DE3) pLysS and its expression was induced by IPTG, the lysis supernatant of the engineering strain was purified by Ni-NTA resin and then the target rhIL-11 was digested by auto-cleavaged DsbA-EKL-(His)(8). The results showed that after affinity chromatography, Trx-IL-11 was obtained with the yield of 11.25mg/g, the purity of 89.2% and the recovery of 91.8%. Finally the target rhIL-11 was digested and purified to over 95%. In conclusion, the preparation method of rhIL-11 from fusion protein by using enterokinase is simple and feasible with good separation, which can meet industrial requirements.