重组七鳃鳗PHB2蛋白的原核表达及纯化

Prokaryotic expression and purification of recombined lamprey PHB2 protein

为了研究PHB2蛋白的生物学活性及后续抗体的制备,作者以前期构建的p MD18-T-Lm-PHB2质粒为模板,PCR扩增Lm-PHB2基因全长CDS区,PCR产物经Hind III和Eco R I双酶切后连接至表达载体p ET-32a,构建重组质粒p ET-32a-Lm-PHB2。将鉴定正确的重组质粒转化入大肠杆菌(Escherichia coli)Rosetta Blue,经IPTG诱导表达后,表达产物通过SDS-PAGE和Western blotting进行检测,利用镍柱亲和层析纯化得到纯度较高的目的蛋白r Lm-PHB2。结果表明,经PCR、双酶切和测序鉴定,所构建的重组质粒p ET-32a-Lm-PHB2序列正确,表达产物存在于裂解菌液的上清和沉淀中,经SDS-PAGE和Western blotting证实在约47 ku处有目的蛋白r Lm-PHB2的表达条带。本研究构建了重组七鳃鳗(Lampetra japonica)PHB2蛋白的原核表达载体,并大量表达和纯化目的蛋白,为该蛋白后续的抗体制备及生物活性研究奠定了基础。

To study the in vivo biological activities of lamprey PHB2 protein and prepare the antibody of PHB2 protein, herein, we aimed to construct the soluble prokaryotic expression vector of Lm-PHB2, and obtain adequate amount of purified r Lm-PHB2 protein. The Lm-PHB2 gene was amplified from the previously constructed p MD18-T-Lm-PHB2 plasmid template. The PCR products were subjected to Hind III and Eco R I digestion and then linked to a soluble expression vector p ET-32 a. The identified recombinant plasmid p ET-32a-Lm-PHB2 was transformed into Rosetta Blue, and IPTG induced expression of r Lm-PHB2 was confirmed by SDS-PAGE and Western blotting assay. The r Lm-PHB2 fusion protein was purified using His affinity chromatography purification system to get highly purified protein. The correct construction of recombinant plasmid p ET-32a-Lm-PHB2 was confirmed by PCR, restriction enzyme digestion and gene sequencing identification. Expression products were verified to present in the supernatant of bacteria lysis, indicting the successful soluble expression of r Lm-PHB2. The SDS-PAGE and Western blotting results showed that the molecular weight of r Lm-PHB2 protein was about 47 ku, corresponding with the anticipant size. The p ET-32a-Lm-PHB2 prokaryotic expression vector was constructed correctly, and the soluble r Lm-PHB2 protein was successfully expressedsucceeded. Ultimately, the r Lm-PHB2 protein with high purity was obtained after purification.