ubiCA基因的强化表达及对大肠杆菌辅酶Q生物合成的影响

Effect of Overexpressing ubiCA Genes Responsible for Ubiquinone Biosynthesis on Ubiquinone Production in Escherichia coli

为调查大肠杆菌高产辅酶Q(CoQ)的可能性,首先研究大肠杆菌生物合成关键基因ubiCA强化表达对大肠杆菌CoQ产量的影响。本文构建了含有ubiCA基因的5个表达质粒,将其分别转入E.coli JM 83或BL 21(DE 3)菌株中,定量分析这些转化子的辅酶Q产量。结果表明ubiCA基因在ubiC自身启动子(pub iCA-lacZF)介导下的表达最有效,重组菌CoQ产量达到对照的3.5倍,由此推测ubiCA基因的表达可能与其启动子序列有关。

To investigate the possibility of high-level production of UQ, ubiCA genes, which encodes enzymes for the first two steps of UQ biosynthesis in Escherichia coli were overexpressed. Five expression plasmids containing ubiCA were constructed and transformed into E. coli JM83 or BL21 （DE3）. Different expression of ubiCA genes resulted in an increase in UQ production to various degrees. Among them the expression under ubiC promoter （pubiCA- lacZF） was most effective. Accordingly we succeeded in achieving a level of UQ production 3.5 times that of the control. Meanwhile, the result suggests that the highlevel expression of ubiCA gene is probably related to the sequence of its own promoter.