在R. rubrum的光合作用增长中,Redox平衡驱动着宏分子通路的大规模变化
William R Cannon1,2, Ethan King3, Katherine A Huening4
1Computational Mathematics Group, Pacific Northwest National Laboratory, Richland, Washington, United States of America.
PLoS computational biology
|June 10, 2025
概括
紫色非硫细菌通过多种电子获取和辅助因子管理来平衡细胞的氧化还原平衡. 这会影响生物合成和宏分子水平,当NADP+/NADPH比率波动时,ATP水解会导致减少.
科学领域:
- 微生物学 微生物学
- 生物化学 生物化学
- 系统生物学 系统生物学
背景情况:
- 紫色非硫细菌,如Rhodospirillum rubrum,利用光异质的生长在有机基板上.
- 电子获取通过有机/无机基质氧化或反向电子流来发生.
- 细胞的氧化还原平衡 (氧化到减少的辅因子比率) 和降低等效消散是复杂的,不太了解.
研究的目的:
- 为了建模和理解光异质增长过程中的氧化还原平衡.
- 研究氧化还原条件对细胞生物合成和宏分子水平的影响.
- 为了澄清反向电子流和ATP在辅因子减少中的作用.
主要方法:
- 基于物理的建模捕捉了质量动作动力学和热力学.
- 评估一系列的氧化还原条件,从热力学平衡到远离平衡.
- 将建模预测与实验测量的整合.
主要成果:
- 氧化可以显著改变生物合成路径活性和宏分子组成 (DNA,RNA,蛋白质,脂肪酸).
- 与基质氧化相比,反向电子流是减少辅助因子生产的较小贡献者.
- 子池主要支持ATP的产生,通过ATP水解驱动减少,即使低NADP+/NADPH.
结论:
- 细胞氧化还原平衡是光异质型细菌中生物合成和宏分子水平的关键调节者.
- 与还原过程相结合的ATP水解在管理细胞氧化还原平衡方面发挥着关键作用.
- 核酸,脂质和蛋白质生产之间的动态相互作用是平衡细胞氧化和还原的重要机制.
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