在Bacillus subtilis中改善纤维素-2-表皮酶表达,以有效地将乳糖生物转化为乳糖
Suchun Xiong1, Zhaolin Huang2, Junmei Ding3
1Engineering Research Center of Sustainable Development and Utilization of Biomass Energy, Ministry of Education, Yunnan Normal University, Kunming 650500, China; State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, China.
International journal of biological macromolecules
|September 28, 2024
概括
研究人员使用工程 Bacillus subtilis.提升了乳糖的生产,一个有益的乳糖衍生物,使用工程 Bacillus subtilis. 这种优化的酶过程显示出对工业规模的乳糖制造有前途.
科学领域:
- 生物技术是生物技术.
- 酶工程是什么? 酶工程是什么?
- 工业微生物学 工业微生物学
背景情况:
- 乳糖衍生物皮素具有益生菌性质和潜在的健康益处,引发人们对其生产的兴趣.
- 纤维素2-胺酶 (CEase) 是将乳糖转化为乳糖的关键酶.
- 为了更广泛的应用,需要有效和可扩展的乳糖生产方法.
研究的目的:
- 为了增强Bacillus subtilis WB600中食品级纤维素-2-表皮酶 (CEase) 的表达,以改善长乳糖的产生.
- 为了识别和优化关键的监管元素 (推动者和N终端编码序列) 高级CEase表达.
- 评估工程菌株在乳糖转化为乳糖的生物转化中的效率.
主要方法:
- 选了七种产生乳糖的CEase,其中Rhodothermus marinus CEase (RmCE) 被选为进一步研究.
- 应用翻译和转录法规,包括对N终端编码序列 (NCS) 和促进体的选,以促进CEase表达.
- 使用摇瓶和食批量方法培养工程 Bacillus subtilis 菌株以确定 CEase 活性.
- 使用产生的CEase.优化乳糖生物转化条件.
主要成果:
- 在Bacillus subtilis表达时,Rhodothermus marinus CEase (RmCE) 显示出最高的表皮化活性.
- 该工程菌株实现了高CEase产量水平:273.6±6.5U/mL (摇动瓶) 和1255±26.4U/mL (食批).
- 仅使用0.25% (V/V) 的料批培养,实现了有效的乳糖生产,将300g/L的乳糖转化为乳糖,在4小时内获得29.5%的产量.
结论:
- 通过监管工程,可以系统地增强Bacillus subtilis WB600中的CEase表达.
- 优化的菌株和生物转化过程为酶性乳糖生产提供了一种高效的方法.
- 这些发现支持了通过酶生物转化来制造乳酪糖的潜在工业化.
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