人β2微球蛋白在大肠杆菌中的表达与纯化  

Human β2-microglobulin expression and purification in Escherichia coli

作　　者：张劲[1] 郭霭光[1] 丰美福[2] 

机构地区：[1]西北农林科技大学生命科学学院,陕西杨凌712100 [2]中国科学院动物研究所生物膜与膜生物工程国家重点实验室,北京100080

出　　处：《西北农林科技大学学报（自然科学版）》2006年第7期87-90,共4页Journal of Northwest A&F University(Natural Science Edition)

基　　金：国家自然科学基金项目(30370383)

摘　　要：β2微球蛋白(β2m)是主要组织相容性复合体(MHC)-Ⅰ类分子的轻链部分,该蛋白的原核表达与纯化是制备MHC-Ⅰ类分子的首要条件。利用已经构建好的β2m原核表达载体pET 23a+β2m,在大肠杆菌(E.coli)中获得稳定表达。原核表达的β2m大部分在包涵体中,包涵体蛋白经充分洗涤、变性(尿素溶解)和复性,并以强阴离子交换柱层析(Q-Sepharose)纯化,获得SDS-PAGE纯的人重组β2m,W estern印迹法分析表明,该蛋白具有与抗人天然β2m抗体反应的特性。Human β2-microglobulin （β2m） is a light chain of major histocompatibility complex （MHC） class- Ⅰ molecule. Expression and purification of this protein in Escherichia coli （E. coli） is a prerequisite to the preparation of MHC- Ⅰmolecule. The expression vector pET23a ＋β2m was presented,in which the complete sequence of β2m gene was inserted. Constant-yield expression of β2m was achieved in E. coli transformed with the expression vector,and most of the recombinant β2m existed in the inclusion body after IPTG induction. The inclusion body was washed extensively and β2m in the inclusion body was solublized with 6 M urea. The β2m was refolded by dialysis and purified by ion-exchange chromatography （Q- Sepharose）. Western blotting assay indicated that the polyclonal antibody against human native β2m could react specifically with the recombinant protein. The purified protein appeared as a single band on both SDSPAGE and Western blotting,indicating that it was chemical and antigenic pure. This work provides the basis for the further study of MHC- Ⅰmolecule.

关 键 词：Β2微球蛋白 重组蛋白 包涵体 复性 

分 类 号：Q78[生物学—分子生物学]