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淡水菌 (Synechococcus elongatus) PCC 7942 不需要一个活跃的外部碳酸无水酶
Elena V Kupriyanova1, Maria A Sinetova1, David A Gabrielyan1
1K.A. Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, 127276 Moscow, Russia.
Plants (Basel, Switzerland)
|August 29, 2024
概括
赛内可可克斯长长菌缺乏自己的碳酸无水酶 (CA) EcaA. 表达外来CA并没有改善其生理学,这表明内部机制调节CA的存在.
科学领域:
- 微生物学 微生物学
- 生物化学 生化学
- 光合作用 光合作用
背景情况:
- 赛内可可克 (Synechococcus elongatus) PCC 7942自然缺乏周等离子体中碳酸酶 (CA) EcaA.
- 碳酸无水酶在蓝藻细菌的碳缩机制 (CCM) 中起着至关重要的作用.
研究的目的:
- 调查表达异质碳酸酶 (EcaACya) 对*Synechococcus elongatus*生理学和适应性反应的影响.
- 阐明CCM相关基因在适应不同无机碳条件时的调节.
主要方法:
- *S. elongatus*的遗传转换,以表达来自 *Cyanothece* sp. 的 EcaACya 的表达. 在ATCC 51142.2. 在ATCC 51142.2.
- 在波动的CO2,HCO3,氧化应激,光应激和高CO2条件下的生理和适应性反应评估.
- 对CCM相关的基因表达模式的分析.
主要成果:
- 在经过测试的环境波动下,EcaACya的表达并没有给S. elongatus带来任何明显的生理优势.
- 与野生类型细胞相比,在Na+耗尽和低CO2条件下,转化剂表现出不利因素.
- 有证据表明,S. elongatus拥有防止其本土EcaASyn的周等离子体局部化的机制.
- 高度的CO2抑制了NDH-1系统,挑战了以前关于其构成功能的假设.
结论:
- 在S. elongatus中缺少EcaASyn可能是由于活跃的调节机制.
- 碳酸无酶的异质表达不一定会增强S. elongatus*中的碳度机制.
- 包括NDH-14系统在内的CCM相关基因的调节是动态的,对无机碳的可用性有反应.
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