Jojima Toru, Inui Masayuki, Yukawa Hideaki
Research Institute of Innovative Technology for the Earth , Kyoto, Japan.
Appl Microbiol Biotechnol. 2008 Jan;77(6):1219-24. doi: 10.1007/s00253-007-1246-8. Epub 2007 Nov 7.
A genetically engineered strain of Escherichia coli JM109 harboring the isopropanol-producing pathway consisting of five genes encoding four enzymes, thiolase, coenzyme A (CoA) transferase, acetoacetate decarboxylase from Clostridium acetobutylicum ATCC 824, and primary-secondary alcohol dehydrogenase from C. beijerinckii NRRL B593, produced up to 227 mM of isopropanol from glucose under aerobic fed-batch culture conditions. Acetate production by the engineered strain was approximately one sixth that produced by a control E. coli strain bearing an expression vector without the clostridial genes. These results demonstrate a functional isopropanol-producing pathway in E. coli and consequently carbon flux from acetyl-CoA directed to isopropanol instead of acetate. This is the first report on isopropanol production by genetically engineered microorganism under aerobic culture conditions.
一种经过基因工程改造的大肠杆菌JM109菌株，其携带由五个基因组成的异丙醇生产途径，这五个基因编码四种酶，即硫解酶、辅酶A（CoA）转移酶、来自丙酮丁醇梭菌ATCC 824的乙酰乙酸脱羧酶以及来自拜氏梭菌NRRL B593的伯仲醇脱氢酶。在有氧补料分批培养条件下，该菌株从葡萄糖中产生的异丙醇高达227 mM。工程菌株产生的乙酸盐约为携带无梭菌基因表达载体的对照大肠杆菌菌株产生的乙酸盐的六分之一。这些结果证明了大肠杆菌中存在功能性的异丙醇生产途径，从而使乙酰辅酶A的碳通量导向异丙醇而非乙酸盐。这是关于基因工程微生物在有氧培养条件下生产异丙醇的首次报道。
