使用三种细胞外酶生产三糖,通过工程 Bacillus subtilis 菌株的一步发酵生产
Xi Sun1, Jun Yang1, Xiaoping Fu2,3
1College of Biological Engineering, Tianjin Agricultural University, Tianjin 300384, China.
Bioengineering (Basel, Switzerland)
|August 26, 2023
概括
这项研究引入了一种新的一步发酵工艺,用于使用工程 Bacillus subtilis 进行三糖生产. 工程菌株有效地共同表达关键酶,大大提高了三糖转化率,降低了生产成本.
科学领域:
- 生物技术是生物技术.
- 酵素工程是什么? 酶工程是什么
- 工业微生物学 工业微生物学
背景情况:
- 目前的工业三糖生产依赖于一种双酶系统,该系统使用了马尔托利戈西尔三糖合成酶 (MTSase) 和马尔托利戈西尔三糖三糖水酶 (MTHase).
- 这些酶通常通过工程化大肠杆菌的异质表达产生,这在酶制备和成本效益方面提出了挑战.
研究的目的:
- 开发一种更高效,更具成本效益的工业三糖生产方法.
- 设计一种能够共同表达多个酶的微生物菌株,用于单步三糖合成.
主要方法:
- 研究了中性普拉酶 (PulA) 对三糖转化率的增强效应.
- 利用CBM68域来促进Bacillus subtilis中Arthrobacter ramosus S34中的MTSase和MTHase的分泌表达.
- 构建了一个工程 Bacillus subtilis 菌株 (PSH02),用于 MTSase,MTHase 和 PulA. 的共同表达.
主要成果:
- 添加PulA在双酶系统中提高了2.46倍的三糖转化率.
- 经过一步发酵的工程 Bacillus subtilis PSH02 菌株从 100 g/L 马尔托德克斯特林中实现了 80% 的三糖转化率.
- 工程菌株表现出高通道稳定性和多酶保存稳定性.
结论:
- 使用工程 Bacillus subtilis PSH02 开发的一步发酵过程为工业三糖生产提供了简化且潜在降低成本的替代方案.
- 在单个微生物宿主中,MTSase,MTHase和Pula的共同表达是有效合成三糖的可行策略.
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