【摘要】 为了对大肠杆菌中由aroG基因编码的 3 脱氧 D 阿拉伯庚酮糖酸 7 磷酸合成酶 (DAHP合成酶 )进行结构与功能的深入研究 ,尝试了aroG基因在枯草杆菌中的表达 .表达载体以pUB110为骨架 ,采用了枯草杆菌热激蛋白 groESL基因的启动子 ,碱性蛋白酶subtilisin基因的信号肽和N 乙酰胞壁酸 L 丙氨酸酰胺酶cwlB基因的转录终止子 ,将aroG基因在枯草杆菌WB6 0 0宿主菌中进行了分泌表达 .在SDS 聚丙烯酰胺凝胶电泳上可以明显看到与aroG基因表达产物分子质量一致的蛋白条带 ,并在培养基中可以检测到DAHP合成酶的活性 .更多还原

【Abstract】 In Escherichia coli , the key enzyme for biosynthesis of aromatic amino acids, 3 deoxy D arabino heptulosonate 7 phosphate (DAHP) synthase are encoded by three genes, aro G, aro H and aro F. This study showed the expression of E.coli aro G gene in Bacillus subtilis as secreted proteins to benefit the purification and crystallization of the enzyme for structure and function study. The aro G gene was subcloned into expression vector pUB110, with gro ESL promoter, subtilisin signal peptide coding DNA upstream and cwl B terminator downstream. The band corresponding to aro G gene product was shown on SDS polyacrylamide gel electrophoresis, and the DAHP syntase acivity was detected in the culture medium.更多还原