双重 GGDEF-EAL 域蛋白质 类调节 c-di-GMP 代谢 参与细菌纤维素生物合成
Tianzhen Zhang1,2, Shiqi Zhang1,2, Yan Wang1,2
1Key Laboratory of Industrial Fermentation Microbiology (Ministry of Education), Tianjin University of Science & Technology, Tianjin 300457, People's Republic of China.
Journal of agricultural and food chemistry
|January 10, 2025
概括
循环狄加诺辛单酸盐 (c-di-GMP) 调节了细菌纤维素的合成. 向化酶蛋白显著增加了48.1%的BC产量,为工业应用提供了新的策略.
科学领域:
- 微生物学 微生物学
- 生物化学 生物化学
- 分子生物学分子生物学
背景情况:
- 循环狄加诺辛单酸盐 (c-di-GMP) 是一个关键的二次信使,控制细菌纤维素 (BC) 合成.
- 乙基合成由含有GGDEF域的迪加尼酸环酶 (DGC) 和含有EAL域的化酶 (PDE) 调节.
研究的目的:
- 系统地分析 Komagataeibacter xylinus* 中 10 种 GGDEF-EAL 协奏域蛋白的功能.
- 研究这些蛋白质对c-di-GMP代谢,BC产生和细菌运动性的影响.
- 通过操纵c-di-GMP信号来确定增强工业BC生产的策略.
主要方法:
- 在体外酶活性测定DGC和PDE.
- 在GGDEF-EAL蛋白缺乏突变菌株的构建和分析.
- 量化BC标位和分析BC结构.
- 测量细胞内c-di-GMP水平. 在细胞内测量c-di-GMP水平.
主要成果:
- 在10种分析的蛋白质中,有5种显示DGC活性,5种显示PDE活性.
- 一种蛋白质GE03被确定为具有DGC和PDE活动的双功能蛋白.
- 缺乏GGDEF-EAL蛋白质的突变菌株表现出改变的BC代谢,运动性和c-di-GMP水平.
- 与野生类型相比,PDE蛋白质的联合淘汰导致BC标位增加48.1%.
结论:
- 这项研究阐明了GGDEF-EAL蛋白在*K. xylinus*中调节c-di-GMP代谢和BC合成中的多种作用.
- 针对特定的PDE蛋白质提供了一个有前途的策略,可以显著提高工业BC生产.
- 这些发现为优化细菌纤维素制造的c-di-GMP信号通路提供了新的见解.
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