厌氧异样化酸盐氧化,微生物电子经济的极其高效的概念
Zhuqing Mao1,2, Nicolai Müller1, Sabrina Borusak1,2
1Department of Biology, University of Konstanz, Constance, Germany.
Environmental microbiology
|August 1, 2023
概括
一些无氧细菌利用酸盐作为能量来源,将其氧化为酸盐. 这一对于生命早期至关重要的过程,通过NADH和Wood-Ljungdahl通路有效地将基质电子转化为生物质.
科学领域:
- 微生物学 微生物学
- 生物化学 生物化学
- 天体生物学 天体生物学
背景情况:
- 和酸盐是早期地球上重要的成分.
- 酸盐对酸盐的氧化释放出低氧化还原潜力的电子 (pH 7.0 的-690 mV).
- 许多细菌使用酸盐作为的来源,但很少有人使用它作为电子捐赠者.
研究的目的:
- 为了研究使用酸盐作为电子捐赠体的无氧细菌.
- 了解关键的酶和代谢途径,参与酸盐氧化产生能量.
主要方法:
- 使用酸盐的无氧细菌的隔离和表征.
- 酶分析以确定酸盐脱酶.
- 电子流和碳固定的代谢分析.
主要成果:
- 确定了两种严格无氧的细菌物种,即Phosphitispora fastidiosa和Desulfotignum phosphitoxidans. 这两种细菌物种被认为是有毒的.
- 一个关键的酶,NAD+依赖的酸盐脱酶,被表征,显示与核酸二酸糖表酶的关系.
- 产生的NADH通过伍德-Ljungdahl通路被引导到自二氧化碳固定中,从而实现了高效的电子同化.
结论:
- 酸盐作为特定无氧细菌能量代谢的电子捐赠者.
- 这种代谢途径,将酸盐氧化与二氧化碳固定联系起来,证明了高效的电子流.
- 这种机制可能在生命的早期进化和能量代谢中发挥了重要作用.
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