从d-Xylose中生产光学纯的 (S) -3-Hydroxy-γ-butyrolactone,使用工程Escherichia coli
Yujin Cao1,2,3, Wei Niu4, Jiantao Guo4
1CAS Key Laboratory of Biobased Materials, Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China.
Journal of agricultural and food chemistry
|December 13, 2023
概括
工程化大肠杆菌有效地从d-xylose中产生光学纯净的 (S) -3-基-γ-butyrolactone ((S) -3HγBL). 这种生物合成途径提供了一种可持续的方法来生产这种具有高反体过剩的有价值化学物质.
科学领域:
- 生物技术是生物技术.
- 合成生物学 合成生物学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 生物催化为不对称合成提供了高的立体选择性.
- 性化合物的酶性生产对于制药和精细化学品至关重要.
- (S) - 3 - 基-γ - - 丁拉克 ((S) - 3HγBL) 是一种有价值的性构建块.
研究的目的:
- 建立一个高效的生物合成途径,用于光学纯 (S) - 3HγBL生产,使用工程Escherichia coli.
- 优化工程菌株和发酵过程,以提高 (S) - 3HγBL的产量和生产力.
- 为了证明使用可再生d-氧化原料的可持续生产方法.
主要方法:
- 构建了一个模仿1,2,4-butanetriol路径的五步生物合成路径.
- 使用关键酶的工程大肠杆菌:d-xylose脱酶,d-xylonolactonase,d-xylonate脱酶,2-keto酸脱酶和化脱酶.
- 通过破坏竞争途径并采用料批发发酵来优化菌株.
主要成果:
- 经过工程设计的大肠杆菌成功地将d-克西洛斯转化为 (S) - 3HγBL,其高反体过量 (ee) 为99.3%.
- 优化的菌株达到最高 (S) - 3HγBL标位3.5g/L.
- 体积生产率和摩尔产量分别达到50.6 mg/L·h和52.1%.
结论:
- 使用工程化大肠杆菌成功建立了 (S) - 3HγBL生产的高效和可持续的生物合成途径.
- 该过程利用可再生的d-xylose,为传统化学合成提供了一个环保的替代方案.
- 进一步的代谢工程和发酵优化可以提高 (S) - 3HγBL的生产效率.
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