在Streptococcus thermophilus AR333中用于外聚糖生物合成的工程UDP-糖合成途径
Yizhou Fan1, Junkang Shi1, Xin Song1
1Shanghai Engineering Research Center of Food Microbiology, School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai, China.
Journal of the science of food and agriculture
|March 3, 2025
概括
代谢工程通过准UDP-糖路径来增强Streptococcus thermophilus中的外聚糖 (EPS) 生产. 基因改造显著提高了EPS产量,为乳制品的工业应用铺平了道路.
科学领域:
- 微生物学 微生物学
- 生物技术是生物技术.
- 食品科学 食品科学 食品科学
背景情况:
- 来自Streptococcus thermophilus的外聚糖 (EPS) 提高了乳制品的质量,但其产量很低,阻碍了工业使用.
- 代谢工程提供了一种有前途的策略,以增强S. thermophilus中的EPS生物合成.
研究的目的:
- 系统地研究UDP-糖合成路径的工程,以增加S. thermophilus中的EPS生产.
- 识别UDP-糖代谢中的关键基因,这些基因可以被操纵以提高EPS产量.
主要方法:
- 通过调节EPS前体UDP-葡萄糖和UDP-银糖的生物合成基因,改造Streptococcus thermophilus AR333.
- 针对参与UDP-糖合成的特定基因,利用单个和协同过度表达策略.
- 进行了转录分析,以了解遗传修饰对EPS基因集群的影响.
主要成果:
- 八个EPS前体基因的单次过度表达导致EPS产量的7-31%增加.
- 过度表达的glk (葡萄糖酶) 和galE1 (UDP-Galactose-4-epimase) 导致显著的EPS产量分别为275.37和288.65毫克L-1.
- lacZ (β-galactosidase) 和galE1的联合过度表达达达到了49%的增加,达到329.51毫克L-1EPS,有前体和EPS基因集群上调的证据.
结论:
- 工程UDP-糖合成途径是提高S. thermophilus.中EPS生产的有效策略.
- 像glk,galE1和lacZ这样的特定基因标显示出显著的EPS产量改善的潜力.
- 这项研究为优化S. thermophilus的工业规模EPS生产提供了基础.
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