肺炎链球菌热休克蛋白GrpE的表达、纯化及热稳定性研究

Expression，purification and thermal stability of heat shock protein GrpE from Streptococcus pneumonia

摘要:

1. 重庆医科大学检验医学院临床检验诊断重点实验室，重庆 400016；2. 成都中医药大学附属医院检验科，成都 610072；3. 感染性疾病分子生物学教育部重点实验室，重庆 400016；4. 重庆市渝北区人民医院医学检验科，重庆 402220

Abstract:

Objective：Streptococcus pneumonia is a major cause of several diseases. To express and purify the heat shock protein GrpE from Streptococcus pneumonia in order to uncover the infectious mechanism. Methods：Being amplified by PCR，the open reading frame of GrpE was subcloned into pW28 and expressed in escherichia coli（E.coli） B834. The bacterial protein was purified by nickel chro－matography column and anion-exchange chromatography column subsequently. The aggregation of GrpE in solution was analyzed by gel filtration column（Hiload Superdex 75） and its thermal stability was characterized with thermal shift assay（TSA） method. Results：The GrpE protein was expressed in E.coli B834 as soluble. The purified protein with high purity of 95.0% exhibited homodimer in solutions. The recombinant GrpE protein presented relative stabilization in a solution at pH 6.0 and 20 mmol/L NaCl. Conclusion：The GrpE protein with high purity was expressed in E.coli B834 and its thermal stability was determined with TSA method.