在高细胞密度菌株Bacillus subtilis中控制表面蛋白生产的遗传密码扩展
Alexander Hermann1, Eric Hiller1, Philipp Hubel2
1Department of Bioprocess Engineering, Institute of Food Science and Biotechnology, University of Hohenheim, 70599 Stuttgart, Germany.
Microorganisms
|February 26, 2025
概括
*B. subtilis*的遗传密码扩展精确地控制了使用非正规氨基酸的表面蛋白生产. 这种方法实现了高产量,并允许对生物活性代谢物生物合成的转录后调节.
科学领域:
- 生物技术是生物技术.
- 合成生物学 合成生物学
- 代谢工程是代谢工程.
背景情况:
- 细菌细菌是异质蛋白和生物活性代谢物生产的关键生物体.
- 表面素是一种由*B. subtilis*产生的脂,是一种有价值的生物活性代谢产物.
- 控制参与二次代谢物生物合成的酶的表达,如表面素,对于优化生产至关重要.
研究的目的:
- 引入和证明B. subtilis*中遗传密码扩展的原则,以控制表面素的生产.
- 建立一种用于转录后调节生物活性代谢物生物合成的方法.
- 通过工程生物合成实现高产量的表面素.
主要方法:
- 工程 *B. subtilis* 在 *srfA* 操作符中带有珀色停止符号.
- 结合了来自*Methanococcus jannaschii*的氨基酸-tRNA合成酶/tRNA对,用于局部导向的O-甲基-L-氨酸 (OMeY) 的结合.
- 通过HPTLC利用料批生物反应器发酵和量化表面素生产;使用质谱蛋白质组学分析了菌株适应.
主要成果:
- 成功证明了与OMeY添加相关的表面素生物合成的遗传密码扩展.
- 在与OMeY相关的料批发发酵中达到10.8g/L的最大表面素标位.
- 蛋白质组分析揭示了B. subtilis的适应性,包括减少运动性和增加表面素前体生成酶的丰度.
结论:
- 遗传密码的扩展为*B. subtilis*的表面素生物生产提供了精确的转录后控制.
- 这种方法可以使用本地促进器系统实现诱导器相关调节.
- 促进目标代谢物形成酶的受控生产,以提高生物活性二次代谢物产量.
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