一种简便快速工艺制备重组人胸腺肽α1

将构建的含有胸腺肽α₁融合蛋白的编码基因插入表达质粒pET28a(+)中，并在大肠杆菌BL21中进行表达，该菌经IPTG诱导融合蛋白高表达后，离心收集菌体，超声波破碎，包含体裂解，目标蛋白质的体外变性复性后，经DEAE-Sepharose Fast Flow阴离子交换层析纯化，每升菌液中可获得260mg融合蛋白。经重组肠激酶酶切反应、Ni-Sepharose亲和层析，Sephadex G-25柱纯化后，得到了纯度达97%的重组人胸腺肽α₁，该纯化工艺简单快速，经三步层析即可得到纯度达97%的重组人胸腺肽α₁，且产量达82mg/L，为大批量用细菌表达重组人胸腺肽α₁及纯化提供了参考。

A simple and rapid process for preparing rhthymosin α1 with transgenic Escherichia coli

Human thymosin α₁, a small hormone with a length of 28 amino acids, is a powerful antiviral drug for treatment of HBV, SARS and various cancers. After consideration of the feasibility of producing human thymosin α₁ on a large scale, an over-expression vector has been constructed based on the plasmid pET28a(+). After induction by isopropyl β-D-1-thiogalactopyranoside (IPTG), the observed yield of crude fusion proteins was up to 260mg/L. In order to obtain the purified target proteins, three different chromatographic columns, namely DEAE-Sepharose FF, Ni-chelating-Sepharose and Sephadex G-25, were operated in series. The purity of the resulting rhThymosin α₁ was more than 97%, as shown by RP-HPLC analysis. Finally, 82?mg of purified rhThymosin α₁ was obtained from a 1 liter culture.