INTRODUCTIONHelicobacter pylori (H . pylori) is associated with the development of chronic gastritis ,peptic ulcer and gastric cancer and gastric MALT lymphoma[1-9],H .pylori has many antigens ,including urease ,heat ...INTRODUCTIONHelicobacter pylori (H . pylori) is associated with the development of chronic gastritis ,peptic ulcer and gastric cancer and gastric MALT lymphoma[1-9],H .pylori has many antigens ,including urease ,heat shock protein and vacuolating cytotoxin and so on ,and urease is an important factor in the colinization of the gastric mucosa and suspected to cause damage to the gastric mucosa[10-14].At the same time ,urdase is also one of the important protective antigens .展开更多
Eukaryotic membrane proteins, many of which are key players in various biological processes, constitute more than half of the drug targets and represent important candidates for structural studies. In contrast to thei...Eukaryotic membrane proteins, many of which are key players in various biological processes, constitute more than half of the drug targets and represent important candidates for structural studies. In contrast to their physiological significance, only very limited number of eukaryoUc membrane protein structures have been obtained due to the technical challenges in the genera- tion of recombinant proteins. In this review, we examine the major recombinant expression systems for eukaryotic membrane proteins and compare their relative advantages and disadvantages. We also attempted to summarize the recent technical strategies in the advancement of eukaryotic membrane protein purification and crystallization.展开更多
Ara h 1是花生中含量最高的过敏原,也是致敏性较高的蛋白之一。目前提纯Ara h 1的方法大多涉及2至3步柱层析,步骤繁琐且成本较高。本文中,将带有6×his标签的Ara h 1基因与pET-32a表达载体融合,构建重组质粒并转化大肠杆菌BL21(DE3)...Ara h 1是花生中含量最高的过敏原,也是致敏性较高的蛋白之一。目前提纯Ara h 1的方法大多涉及2至3步柱层析,步骤繁琐且成本较高。本文中,将带有6×his标签的Ara h 1基因与pET-32a表达载体融合,构建重组质粒并转化大肠杆菌BL21(DE3)pLysS,诱导使其表达目标蛋白。菌体裂解后使用Ni-NTA吸附、梯度洗脱对Ara h 1进行纯化。采用质谱及Western-blot鉴定纯化蛋白的种类及免疫活性。结果显示,质粒中目标基因的序列与NCBI数据库中Ara h 1的基因数据相符;300 mmol/L异丙基-β-D-硫代吡喃半乳糖苷22℃诱导菌液22 h时蛋白表达量最高;添加15 mmol/L十二烷基磺酸钠可将蛋白释放到上清液中,使用含50,100 mmol/L咪唑的洗脱液分别洗脱2次和1次后得到纯度较高且免疫原性良好的重组Ara h 1。展开更多
目的表达和纯化人脂联素(adiponectin,APN)球状结构域并观察其生物学活性。方法用PCR方法复制人脂联素球状结构域(globular domain of adiponectin,gAPN)的cDNA,并克隆于pET28a(+)原核表达载体中。将重组表达质粒pET28a(+)-gAPN转化大...目的表达和纯化人脂联素(adiponectin,APN)球状结构域并观察其生物学活性。方法用PCR方法复制人脂联素球状结构域(globular domain of adiponectin,gAPN)的cDNA,并克隆于pET28a(+)原核表达载体中。将重组表达质粒pET28a(+)-gAPN转化大肠埃希菌BL21(DE3),37℃培养至A600达到0.6时,加入异丙基-β-D-硫代半乳糖苷(IPTG)诱导目的蛋白的表达。细菌经超声破菌,得到粗提的包涵体洗涤变性后经镍柱亲和层析柱一步纯化,获得纯化的gAPN重组蛋白,复性后冻干保存。然后,用链佐星(streptozocin,STZ)诱导的小鼠高血糖模型检测其生物活性。结果IPTG诱导后有Mr约为17 000大小的目的蛋白表达,免疫印迹结果进一步表明,其具有人gAPN的抗原性。表达蛋白主要以包涵体形式存在,占菌体蛋白的30%以上,表达产物经变性、纯化、复性,可获得纯度90%以上的目的蛋白。该重组蛋白能够降低STZ诱导的小鼠高血糖模型的血糖水平。结论在大肠埃希菌BL21(DE3)中成功表达了人gAPN蛋白,经变性、纯化、复性后得到具有生物学活性的蛋白。展开更多
基金Supported by the National Major Science and Technology Projects,No.96-901-01-54.
文摘INTRODUCTIONHelicobacter pylori (H . pylori) is associated with the development of chronic gastritis ,peptic ulcer and gastric cancer and gastric MALT lymphoma[1-9],H .pylori has many antigens ,including urease ,heat shock protein and vacuolating cytotoxin and so on ,and urease is an important factor in the colinization of the gastric mucosa and suspected to cause damage to the gastric mucosa[10-14].At the same time ,urdase is also one of the important protective antigens .
基金ACKNOWLEDGEMENTS We apologize to colleagues whose work could not be cited due to the scope of this review. We would like to thank members in Yan laboratory for discussions. We thank Brendan Lehnert, Xinlei Sheng, Quanxiu Li, Dan Ma and Xinhui Zhou for critical reading. This work was supported by funds from the National Basic Research Program (973 Program) (No. 2011CB910501), the National Natural Science Foundation of China (Grant Nos. 31321062-20131319400, 31125009, and 91017011 ), and funds from Tsinghua-Peking Center for Life Sciences. The research of N.Y. was supported in part by an International Early Career Scientist grant from the Howard Hughes Medical Institute.
文摘Eukaryotic membrane proteins, many of which are key players in various biological processes, constitute more than half of the drug targets and represent important candidates for structural studies. In contrast to their physiological significance, only very limited number of eukaryoUc membrane protein structures have been obtained due to the technical challenges in the genera- tion of recombinant proteins. In this review, we examine the major recombinant expression systems for eukaryotic membrane proteins and compare their relative advantages and disadvantages. We also attempted to summarize the recent technical strategies in the advancement of eukaryotic membrane protein purification and crystallization.
文摘Ara h 1是花生中含量最高的过敏原,也是致敏性较高的蛋白之一。目前提纯Ara h 1的方法大多涉及2至3步柱层析,步骤繁琐且成本较高。本文中,将带有6×his标签的Ara h 1基因与pET-32a表达载体融合,构建重组质粒并转化大肠杆菌BL21(DE3)pLysS,诱导使其表达目标蛋白。菌体裂解后使用Ni-NTA吸附、梯度洗脱对Ara h 1进行纯化。采用质谱及Western-blot鉴定纯化蛋白的种类及免疫活性。结果显示,质粒中目标基因的序列与NCBI数据库中Ara h 1的基因数据相符;300 mmol/L异丙基-β-D-硫代吡喃半乳糖苷22℃诱导菌液22 h时蛋白表达量最高;添加15 mmol/L十二烷基磺酸钠可将蛋白释放到上清液中,使用含50,100 mmol/L咪唑的洗脱液分别洗脱2次和1次后得到纯度较高且免疫原性良好的重组Ara h 1。
文摘目的表达和纯化人脂联素(adiponectin,APN)球状结构域并观察其生物学活性。方法用PCR方法复制人脂联素球状结构域(globular domain of adiponectin,gAPN)的cDNA,并克隆于pET28a(+)原核表达载体中。将重组表达质粒pET28a(+)-gAPN转化大肠埃希菌BL21(DE3),37℃培养至A600达到0.6时,加入异丙基-β-D-硫代半乳糖苷(IPTG)诱导目的蛋白的表达。细菌经超声破菌,得到粗提的包涵体洗涤变性后经镍柱亲和层析柱一步纯化,获得纯化的gAPN重组蛋白,复性后冻干保存。然后,用链佐星(streptozocin,STZ)诱导的小鼠高血糖模型检测其生物活性。结果IPTG诱导后有Mr约为17 000大小的目的蛋白表达,免疫印迹结果进一步表明,其具有人gAPN的抗原性。表达蛋白主要以包涵体形式存在,占菌体蛋白的30%以上,表达产物经变性、纯化、复性,可获得纯度90%以上的目的蛋白。该重组蛋白能够降低STZ诱导的小鼠高血糖模型的血糖水平。结论在大肠埃希菌BL21(DE3)中成功表达了人gAPN蛋白,经变性、纯化、复性后得到具有生物学活性的蛋白。