欢迎访问过程工程学报, 今天是

›› 2005, Vol. 5 ›› Issue (4): 446-449.

• 生化工程专栏 • 上一篇    下一篇

重组大肠杆菌高密度发酵中乳糖诱导表达hBLyS

李兆鹏,张栩,徐斌,宋礼华,谭天伟   

  1. 北京化工大学生命科学学院
  • 出版日期:2005-08-20 发布日期:2005-08-20

Expression of Hblys in the E. coli High Cell Density Culture Using Lactose as an Inducer

LI Zhao-peng,ZHANG Xu,XU Bin,SONG Li-hua,TAN Tian-wei   

  1. College of Life Science and Technology, Beijing University of Chemical Technology
  • Online:2005-08-20 Published:2005-08-20

摘要: 研究了乳糖代替异丙基硫代半乳糖苷(IPTG)诱导大肠杆菌表达重组人B淋巴细胞刺激因子(hBLyS). 结果表明,乳糖不仅能够作为诱导剂诱导外源蛋白的合成,而且能作为碳源促进菌体的生长. 通过对诱导条件进行优化,乳糖诱导外源蛋白的表达量约占菌体总蛋白的14.3%,达到IPTG的诱导水平(26%)的55%. 在5 L发酵罐中hBLyS的表达量达到16%,同时生物量OD600=62.

关键词: 大肠杆菌, 乳糖, IPTG, hBLyS

Abstract: B lymphocyte stimulator (BLyS) is a recently identified member of the tumor necrosis factor (TNF) superfamily, which stimulates B lymphocyte's proliferation and differentiation. The process of expression of hBLyS (human B Lymphocyte cell stimulator) gene under the control of T7 promoter in Escherichia coli was investigated. Lactose was used as an inducer instead of the expensive nonmetabolizable analog of lactose, IPTG. IPTG is satisfactory for small-scale expressions, but not suitable for large-scale fermentations due to its high cost. It was found that lactose could induce foreign protein expression and enhance cell growth during the induction period. Through proper optimization of culture and induction conditions, an expression level near 14.3% of total cellular protein was achieved in the shake flask. This hBLyS expression level reached about 55% of the level (26%) with IPTG as inducer. And in 5 L fermentor, a high cell density OD600=62 and high expression level of hBLyS about16% of the total cell protein were obtained.

Key words: E. coli, lactose, IPTG, hBLyS