敲除aceE基因对大肠杆菌生长和丙酮酸代谢的影响

大肠杆菌aceE基因是编码丙酮酸脱氢酶多酶复合体PdhR的关键酶之一。利用Red重组系统敲除大肠杆菌MG1655的aceE基因后,阻断了丙酮酸流向TCA循环,导致丙酮酸的累积,也使菌体生长受到影响,在培养基中补加5 g/L KAc后可以在一定程度上弥补菌株在生长上的缺陷。摇瓶发酵36 h,MG1655没有积累丙酮酸,MG1655ΔaceE∷cat菌株可以积累26.77 g/L丙酮酸,为利用大肠杆菌发酵生产丙酮酸奠定了基础。

Effects of aceE gene knockout on growing and pyruvate biosynthesis of E. coli

Gene aceE encoding was one of the key enzymes of pyruvate dehydrogenase complex regulator. Using Red recombination, the gene aceE of E. coli MG1655 was knockouted to block the pyruvate flow TCA cycle, causing pyruvate accumulation and growth deficiency. The medium supplemented with 5 g/L KOAc could make up the growth defect to a certain extent strains. MG1655AaceE ：： cat in shake flask fermentation for 36 h could produce pyruvate with 26.77 g/L, initial strain MG1655 did not produce pyruvate.