在海洋菌Trichodesmium中分离固和氧光合作用
I Berman-Frank1, P Lundgren, Y B Chen
1Environmental Biophysics and Molecular Ecology Program, Institute of Marine and Coastal Sciences, Rutgers University, 71 Dudley Road, New Brunswick, NJ 08901, USA. irfrank@imcs.rutgers.edu
概括
通过光合作用和酶活动的时间和空间分离,Trichodesmium蓝藻细菌的海洋固被保护免受氧气损伤. 光系统I减少氧气,保护这一重要过程.
科学领域:
- 海洋微生物学 海洋微生物学
- 生物化学 生物化学
- 进化生物学是进化的生物学.
背景情况:
- 纤维状,非异质囊状蓝藻细菌,特别是三,是海洋固的主要贡献者.
- 固化发生在光周期期间,与氧光合作用相吻合,但酶酶对氧很敏感.
- 保护基酶免受光合作用氧气的影响机制一直是一个长期存在的问题.
研究的目的:
- 阐明化酶在Trichodesmium中同时进行光合作用和固定的保护机制.
- 研究这些过程在光周期内的时间和空间分离.
主要方法:
- 使用快速重复率度测量 (FRRf) 来评估光合作用活性.
- 采用光运动显微镜 (FKM) 来可视化空间和时间动态.
- 研究了线性光合作用电子传输在氧气管理中的作用.
主要成果:
- 在光周期内证明了 (N2) 固定和光合作用的时间和空间分离.
- 确定了线性光合作用电子传输,特别是在光系统I (PSI) 中,作为一个关键的保护机制.
- 表明PSI积极减少光合作用进化的氧气,从而保护酶.
结论:
- 基酶被光合作用电子运输链,特别是PSI,保护免受氧气的影响,PSI消耗进化的O2.
- 这种机制使得固化在Trichodesmium中与氧光合作用同时发生.
- 假设PSI在为酸酶提供无氧微环境方面的作用对早期的蓝藻细菌具有进化上的优势.
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