生物活性肽Lunasin的原核表达和分离纯化

目的：利用基因工程的方法在大肠杆菌中表达并纯化生物活性肽Lunasin。方法：将合成的Lunasin基因插入原核表达载体pET-32a（＋）的多克隆位点Nde I和Xho I之间,然后将重组载体转化入大肠杆菌BL21（DE3）中,利用IPTG诱导表达蛋白,经SDS-PAGE和Western Blot鉴定蛋白的表达。然后利用亲和层析技术将含有6×His标签的蛋白分离纯化、脱盐、冻干。结果：①鉴定结果表明在6kDa位置出现目的条带Lunasin重组蛋白。②亲和层析在100mM咪唑时得到了洗脱的重组蛋白。结论：在大肠杆菌BL21（DE3）中成功表达并且纯化出了生物活性肽Lunasin。

Prokaryotic Expression and Purification of Bioactive Peptide Lunasin

Objective：To express prokaryotic and purify bioactive peptide Lunasin in E.coli by genetic engineering methods.Methods：The gene of Lunasin was artificially synthetic and then inserted into Nde I and Xho I enzyme-cutting sites of pET-32a（＋） plasmid.The recombinant expression vector pET-32a（＋）-Lunasin-6His was transformed into E.coli BL21（DE3）.The fusion protein Lunasin was solubly expressed after the induction of IPTG.The fusion protein was identified by SDS-PAGE and Western Blot.After the expressed protein was purified by affinity binding chromatography with Ni-NTA,salt-out and freeze-dried.Results：① The molecular mass of Lunasin-6His was 6kDa.② The fusion protein was eluted by 100 mM Imidazole.Conclusion：Bioactive peptide Lunasin was successfully expressed and purified in E.coli BL21（DE3）.