在鱼沼湖中,电活性细菌浮游生物的神秘循环
Charles N Olmsted1,2,3, Mark Gahler2, Eric Roden4
1Department of Molecular and Environmental Toxicology, Universities of Wisconsin, Madison, Wisconsin, USA.
Applied and environmental microbiology
|June 20, 2025
概括
湖中的细菌群体使用光驱的细胞外电子转移 (EET) 来循环溶解有机物 (DOM). 这一过程影响了湖泊的新陈代谢和甲排放,并观察到天气和季节性模式.
科学领域:
- 环境微生物学 环境微生物学
- 生物地质化学生物地质化学
- 水生生态学 水生生态学
背景情况:
- 细胞外电子转移 (EET) 是湖细菌浮游生物中常见的遗传特征,但其生态意义尚未得到充分理解.
- 以前的研究预测了ETT的实质性生态作用,但直接证据有限.
- 溶解有机物 (DOM) 循环在水生生态系统中至关重要,影响氧化还原条件和微生物代谢.
研究的目的:
- 为了研究一个假设,无氧的光性电和异性电循环DOM在氧化和减少状态之间在湿湖.
- 探索由光依赖光合作用和相关的电生成过程驱动的微生物活动中的度振荡.
- 确定EET对湖细菌浮游生物代谢的生态贡献及其对生物地球化学循环的影响.
主要方法:
- 美国威斯康星州特劳特博格湖实地分析,包括深度离散的元基因组,生化和电化学分析.
- 开发和部署一个自动浮标,同时测量多个电极对之间的电流流量.
- 将现场数据与已发表的元转录组分析集成在一起,以确定电活性微生物群落和代谢途径.
主要成果:
- 观察到与阳光相关的氧化降解潜力 (ORP) 的变化,在深处与具有EET基因的无氧光开始.
- 测量的电流流量显示与阳光的相关性,表明光驱动的电子消耗.
- 证据表明,在DOM涉及的*Chlorobium*的光氧化和*Geothrix*的无氧呼吸之间存在电子循环,以及季节性ORP在hypolimnion的增加.
结论:
- 电活性DOM调解了湖中的电活性细菌的生态,驱动了和季节性氧化还原模式.
- EET在湖泊新陈代谢中起着不可或缺的作用,扩展到无毒区,并在夏季持续比之前预期的更长时间.
- 这些发现对理解和管理来自湖的温室气体排放,特别是甲的排放有重大影响.
关键词:
氧化是一种.细菌和浮游生物的存在.碳排放的碳排放量是什么一个神秘的循环.溶解的有机物质是一种有机物质.生态学生态学是什么电活性的电动活动体.电otrophic电otrophic电otrophic电otrophic电otrophic电otrophic电otrophic电otrophic电otrophic电otrophic电otrophic电otrophic电otrophic电otrophic电otrophic电otrophic电otrophic电otrophic电otrophic电otrophic电otrophic电otrophic电otrophic电otrophic电otrophic电otroph电otroph电otroph电otroph电otroph电otroph电otroph电otroph电otroph电otroph电otroph电otroph电otroph电otroph电otroph电otroph电otroph电otroph电otroph电otroph电otroph细胞外电子转移 细胞外电子转移氧化降低潜在的氧化.
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