利用肠激酶加工融合蛋白的方法制备rhIL-11

Preparation of rhIL-11 from Fusion Protein by Using Enterokinase

本研究探讨利用肠激酶加工融合蛋白的方法制备重组人白细胞介素11(rhIL-11)的工艺条件与参数。融合表达载体pET32a/IL-11在大肠杆菌E.coliBL21(DE3)pLysS中诱导表达,裂解上清以Ni-NTA亲和纯化,通过DsbA-EKL-(His)8的自催化切割完成单体活性肠激酶催化亚基的释放,继而对Trx-IL-11行使酶促切割作用制备rhIL-11。结果表明:亲和纯化得重组融合蛋白Trx-IL-11 11.25 mg/g湿菌,产品纯度达89.2%,回收率为91.8%。酶切体系经Ni-NTA resin充分吸附后,目标产品单体rhIL-11纯度大于95%。结论:利用肠激酶加工融合蛋白以制备rhIL-11的方法简单可行,分离纯化效果好,能够满足工业生产的需要。

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.