Tashiro Miki, Fujii Akira, Kawai-Noma Shigeko, Saito Kyoichi, Umeno Daisuke
Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Chiba University.
J Gen Appl Microbiol. 2017 Nov 17;63(5):287-295. doi: 10.2323/jgam.2017.01.006. Epub 2017 Sep 26.
To achieve an efficient production of geraniol and its derivatives in Escherichia coli, we aimed to improve the activity of geraniol synthase (GES) through a single round of mutagenesis and screening for higher substrate consumption. We isolated GES variants that outperform their parent in geraniol production. The analysis of GES variants indicated that the expression level of GES was the bottleneck for geraniol synthesis. Over-expression of the mutant GES with a 5'-untranslated sequence designed for high translational efficiency, along with the additional expression of mevalonate pathway enzymes, isopentenyl pyrophosphate isomerase, and geranyl pyrophosphate synthase, yielded 300 mg/L/12 h geraniol and its derivatives (>1000 mg/L/42 h in total) in a shaking flask.
为了在大肠杆菌中高效生产香叶醇及其衍生物，我们旨在通过一轮诱变和筛选更高的底物消耗来提高香叶醇合酶（GES）的活性。我们分离出了在香叶醇生产方面优于其亲本的GES变体。对GES变体的分析表明，GES的表达水平是香叶醇合成的瓶颈。用设计用于高效翻译的5'-非翻译序列过表达突变型GES，同时额外表达甲羟戊酸途径酶、异戊烯基焦磷酸异构酶和香叶基焦磷酸合酶，在摇瓶中产生了300 mg/L/12 h的香叶醇及其衍生物（总共>1000 mg/L/42 h）。
