摘要: 目的 构建链霉亲和素（streptavidin，SA）和自噬相关基因（Beclin 1）重组质粒，并对融合蛋白SA-Beclin 1进行表达和纯化。 方法 利用基因重组技术将核心SA与Beclin 1序列连接，克隆入pQE80形成pQE80-SA-Beclin 1重组载体，IPTG诱导融合蛋白原核表达，镍亲和凝胶层析柱纯化融合蛋白，Western blot鉴定。结果 PCR成功扩增核心SA活性中心，酶切鉴定和测序均证实重组载体pQE80-SA-Beclin 1构建成功；IPTG诱导后SA-Beclin 1融合蛋白(含His标签)在大肠杆菌中高效表达，SDS-PAGE分析表达的融合蛋白以包涵体为主，经镍亲和凝胶层析柱纯化得到融合蛋白，Western blot鉴定其相对分子量约为72000kD，与预期相符。结论 本文成功构建了重组质粒并表达纯化了SA-Beclin 1融合蛋白，为进一步研究SA-Beclin 1的功能及临床应用奠定了基础。

Abstract: Objective To construct recombinant plasmid of streptavidin (SA) and autophagy-related genes Beclin1 fusion gene （Beclin 1）and to express and purify SA-Beclin1 fusion protein. Methods The natural core SA sequence and beclin1 gene were cloned into pQE80 to form the recombinant plasmid pQE80-SA-Beclin 1. The expression of fusion protein was induced by IPTG, purified by Ni-NTA agarose and detected by Western-blot. Results The natural core SA was amplified by PCR, restriction enzyme digestion and sequencing results showed that the recombinant plasmid pQE80-SA-Beclin1 was successfully constructed. The fusion protein induced by IPTG was efficiently expressed in E．coli. Fusion protein was detected by SDS-PAGE and purified by Ni-NTA agarose with a molecular weight of 72 000 kD identified by Western blot. Conclusion The SA-Beclin1 fusion protein was successfully expressed and purified, which lay a good basis for further functional research and clinical application of beclin1．