工程 Bacillus subtilis 从乳糖中高效生产功能性分糖酸乳糖
Wenli Zhang1, Suchun Xiong2, Dawei Ni1
1State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, China.
International journal of biological macromolecules
|May 21, 2024
概括
这项研究报告了第一个成功的乳糖生物合成,一种有价值的乳糖衍生物,使用工程 Bacillus subtilis. 优化的工艺实现了高产量,为工业应用铺平了道路.
科学领域:
- 生物技术是生物技术.
- 酶学 是一种酶学.
- 食品科学 食品科学 食品科学
背景情况:
- 乳糖是一种高价值的乳糖衍生物,在药品,营养食品和食品中具有应用.
- 从乳糖中产生乳糖的酶性生产是可能的,使用纤维素-2-胺酶 (CEase).
- 之前的研究重点是乳酪糖的生物合成,而不是乳酪糖,使用食品级的CEase表达.
研究的目的:
- 实现第一个食品级的乳糖生物合成,使用重组细菌 Bacillus subtilis.
- 通过选择最佳的CEases和表达载体来优化乳糖生产.
- 为了微调CEase表达,提高乳糖产量.
主要方法:
- 设计了一种食品级Bacillus subtilis菌株用于乳糖生物合成.
- 选了各种细胞质2-表皮酶 (CEases) 和表达载体.
- 通过调查N端编码序列来优化CEase表达.
- 使用料批量种植用于发酵.
主要成果:
- 确定了Caldicellulosiruptor saccharolyticus CEase和pP43NMK作为最优的组合.
- 达到最高的发酵异构化活性11.6U/mL.
- 通过使用工程B. subtilis.成功生产了乳糖,产量为52.1%.
结论:
- 证明了使用重组细菌 Bacillus subtilis 的乳糖生物合成的可行性.
- 为高产量乳糖生产建立了一个优化的系统.
- 这些发现支持了酶式乳糖合成的工业潜力.
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