【摘要】 采用反向代谢工程的策略,以谷氨酸棒杆菌ATCC 13032野生型为出发菌株,利用无抗性标记的同源重组方法,敲除了编码葡萄糖pts系统关键转运蛋白基因ptsG、ptsH-ptsI和葡萄糖转运系统关键转运蛋白基因abc、abc2和iolt1,得到了5株逐次敲除了相应基因的突变株。结果表明:当以葡萄糖为唯一碳源培养时,CGΔptsG菌株的葡萄糖的消耗是野生型的50%,菌体OD值为1.473;CGΔptsH-ptsI菌株的葡萄糖的消耗是野生型的39.5%,菌体OD值为1.226;CGΔabc菌株的葡萄糖的消耗是野生型的36%,菌体OD值为1.092;CGΔabc2菌株的葡萄糖的消耗是野生型的26.2%,菌体OD值为0.486;CGΔiolt1葡萄糖的消耗和菌体生长OD值为0,实现了谷氨酸棒状杆菌葡萄糖代谢的阻断,说明ptsG、ptsH-ptsI、abc、abc2和iolt1所编码的转运蛋白具有葡萄糖转运功能。更多还原

【Abstract】 In this study, we used the wild-type Corynebacterium glutamicum strain ATCC 13032 as a starting strain to obtain five mutants with knockout of the ptsG and ptsH-ptsI genes as well as the abc, abc2 and iolt1 genes by homologous recombination without resistance marker using reverse metabolic engineering strategies. Our experimental results showed that compared to the wild-type strain, the glucose consumption of the mutant CGΔptsG was 50% using glucose as the sole carbon source, giving an OD value of 1.473, the glucose consumption of the mutant CGΔptsH-ptsI was 39.5%, giving an OD value of 1.226, the glucose consumption of the mutant CGΔabc was 36%, giving an OD value of 1.09, and the glucose consumption of CGΔabc2 was 26.2%, giving an OD value of 0.486, while the mutant CGΔiolt1 could not utilize glucose to grow, suggesting that glucose metabolism of C. glutamicum was blocked. It turned out that the glucose transporter function was controlled by the ptsG, ptsH-ptsI, abc, abc2 and iolt1 genes, encoding transporter proteins.更多还原