在细胞解菌Ruminiclostridium cellulolyticum中的一个GTP驱动的中央碳代谢
Nian Liu1,2, Nicolas Vita1, Marion Holmière1
1Aix Marseille Univ, CNRS LCB, Marseille, France.
Communications biology
|March 30, 2025
概括
这项研究表明,无氧细菌Ruminiclostridium cellulolyticum利用三酸 (GTP) 驱动其中央碳代谢,挑战了以前关于细菌能量货币的假设. 这种由GTP驱动的途径通过酶交换实验显示出灵活性.
科学领域:
- 微生物学 微生物学
- 生物化学 生物化学
- 代谢工程是代谢工程.
背景情况:
- 无氧细菌Ruminiclostridium cellulolyticum表现出对三酸盐 (GTP) 而不是腺三酸盐 (ATP) 的异常偏好,这种偏好主要存在于诸如hexokinase和galactokinase等关键酶中.
- 这种细菌中的果酸酶依赖于酸盐,进一步表明非正规的中央碳代谢途径.
研究的目的:
- 描述R. cellulolyticum的中央碳代谢途径中的所有激酶的核酸偏好.
- 为了阐明驱动这种细菌核心代谢过程的初级能量货币.
- 研究代谢灵活性和设计这种途径的潜力.
主要方法:
- 参与中央碳代谢的个体激酶的生物化学表征.
- 确定每个酶的首选核三酸盐 (NTP) 或核二酸盐 (NDP) 基质.
- 在体内相互交换实验,涉及R. cellulolyticum和Escherichia coli之间的GTP依赖的六酶和ATP依赖的葡萄酶.
主要成果:
- 在该途径的最初阶段,消耗NTP的基因酶被发现是GTP依赖的.
- 下游阶段的基因酶产生NTP,没有显著的核酸偏好.
- 在R. cellulolyticum中,细胞GTP水平与ATP水平相当,支持GTP驱动的新陈代谢.
- 具有交换的六金酶的工程菌株维持了葡萄糖和分糖化合物的代谢,证明了路径的适应性.
结论:
- R. cellulolyticum的中央碳代谢主要由GTP驱动,而不是ATP.
- 这一发现突显了细菌中央代谢途径的意想不到的多样性和灵活性.
- 这项研究为厌氧细菌的代谢工程提供了基础.
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