生物技术通报 ›› 2016, Vol. 32 ›› Issue (8): 214-220.doi: 10.13560/j.cnki.biotech.bull.1985.2016.08.031

• 研究报告 • 上一篇    下一篇

类弹性蛋白标签在大肠杆菌周质空间中表达研究

李晶泉1, 林衡2, 丁宁2, 左晓雪2, 史晋萍2, 徐永平1, 冷春玲3, 杨春光2   

  1. 1. 大连理工大学生命科学与技术学院,大连 116024;
    2. 大连大学医学院,大连 116622;
    3. 辽东学院农学院,丹东 118003
  • 修回日期:2015-12-31 出版日期:2016-08-25 发布日期:2016-08-25
  • 作者简介:李晶泉,女,博士研究生,研究方向:生物化工;E-mail:lijq@takara.com.cn
  • 基金资助:
    国家自然科学基金项目(31370937),大连大学博士启动基金项目(L2010015),大连大学大学生创新创业训练计划项目(2013110)

The Expression of Elastin-like Polypeptide Tag in Periplasmic Space of Escherichia coli

LI Jing-quan1, LIN Heng2, DING Ning2, ZUO Xiao-xue2, SHI Jin-ping2, XU Yong-ping1, LENG Chun-ling3, YANG Chun-guang2   

  1. 1. School of Life Science and Biotechnology,Dalian University of Technology,Dalian 116024;
    2. Medical College,Dalian University,Dalian 116622;
    3. Agriculture College of Eastern Liaoning University,Dandong 118003
  • Revised:2015-12-31 Published:2016-08-25 Online:2016-08-25

摘要: 旨在研究类弹性蛋白[I]40(elastin-like polypeptide[I]40,ELP[I]40)在大肠杆菌周质空间的表达。构建表达载体pIG6LH/ELP[I]40及pIG6LH/ELP[I]40+Trx,分别将构建的表达载体转化入表达宿主菌E. coli BLR(DE3),IPTG诱导表达,采用可逆相变循环(Inverse transition cycling,ITC)技术纯化蛋白。测定ELP[I]40及ELP[I]40+Trx蛋白相变温度(Tt),检测ELP[I]40、ELP[I]40+Trx蛋白浓度及NaCl对相变温度的影响。结果显示,经3轮ITC纯化得到了ELP[I]40、ELP[I]40+Trx蛋白。分别测定ELP[I]40 和ELP[I]40+Trx在10、25、50、75和100 μmol/L浓度下的Tt,其Tt依次为31.5℃、29℃、27℃、26℃、25℃和31.8℃、29.5℃、27.5℃、26℃、25.5℃;测定了不同浓度的NaCl对Tt影响,在ELP[I]40和ELP[I]40+Trx终浓度为25 μmol/L,NaCl浓度为0.25、0.5、0.75、1.00和1.25 mol/L时,分别使ELP[I]40的Tt由29℃降至24.5℃、22℃、19℃、15℃和11.5℃,使ELP[I]40+Trx的Tt由29.5℃降至25℃、23℃、20.2℃、15.5℃和11.8℃。在大肠杆菌周质空间表达的ELP[I]40 与胞内表达的具有相同的理化性质,ELP可作为在大肠杆菌周质空间表达的蛋白质分离纯化标签。

关键词: 类弹性蛋白标签, 硫氧还蛋白, 大肠杆菌, 周质空间, 分离纯化

Abstract: This work aims to investigate the expression of elastin-like polypeptide[I]40(ELP[I]40)in the periplasmic space of Escherichia coli. The expression vectors of pIG6LH/ELP[I]40and pIG6LH/ELP[I]40+Trx were constructed and transfected into E. coli BLR(DE3)and induced to express by IPTG. Recombinant ELP fusion protein were purified by inverse transition cycling(ITC). Inverse temperature transition(Tt)of ELP[I]40 and ELP[I]40+Trx protein were measured. The effects of the concentrations of ELP[I]40 and ELP[I]40+Trx proteins and NaCl on phase-transition temperature were investigated. ELP[I]40 and ELP[I]40+Trx protein were purified by 3 round ITC. When the protein concentration of ELP[I]40and ELP[I]40+Trx were 10 μmol/L,25 μmol/L,50 μmol/L,75 μmol/L,and 100 μmol/L,the Tt were 31.5℃,29℃,27℃,26℃,25℃ and 31.8℃,29.5℃,27.5℃,26℃,25.5℃ respectively. When the final concentrations of ELP[I]40 and ELP[I]40+Trx were 25 mmol/L respectively and the NaCl concentration was 0.25 mol/L,0.5 mol/L,0.75 mol/L,1.00 mol/L,and 1.25 mol/L respectively,the Tt of ELP[I]40 decreased from 29℃ to 24.5℃,22℃,19℃,15℃,and 11.5℃ respectively and the Tt of ELP[I]40+Trx from 29.5℃ to 25℃,23℃,20.2℃,15.5℃,and 11.8℃ respectively. The ELP[I]40 in the periplasmic space of E. coli possessed the same physicochemical properties as the intracellular one,and the ELP could be used as an isolation and purification tag of expressed proteins in E. coli’s periplasmic space.

Key words: elastin-like polypeptide tag, thioredoxin, Escherichia coli, periplasmic space, purification