光合作用在皮秒时间尺度上重新连接
Tomi K Baikie1, Laura T Wey2,3, Joshua M Lawrence2,4
1Cavendish Laboratory, University of Cambridge, Cambridge, UK.
Nature
|March 23, 2023
概括
科学家已经成功地从活细胞的光系统I和II (PSI和PSII) 中直接提取电子. 这一光合作用研究的突破为生物混合能源技术开辟了新的可能性.
科学领域:
- 光合作用研究
- 生物能源
- 生物技术
背景情况:
- 光系统II和I (PSII,PSI) 对于光合作用至关重要,驱动水氧化和电子激活.
- 目前的研究旨在"重新连接"光合作用以提高效率和新的应用,如H2进化.
- 之前的方法集中在终端接受器的电荷提取上,限制了热力学收益.
研究的目的:
- 研究直接从PSI和PSII的光刺激反应中心提取早期电子的可能性.
- 挑战长期以来的信念, 反应中心在光系统结构中是不可接近的.
- 探索用于生物技术应用的光合作用过程的新途径.
主要方法:
- 使用体内超快速瞬时吸收 (TA) 光谱.
- 使用活的蓝菌细胞和分离的光系统.
- 使用外源电子介质,如2,6-二-1,4-基 (DCBQ) 和甲基生物.
主要成果:
- 从光激发的PSI和PSII中成功提取电子.
- 在早期阶段实现了电子提取,
- 假定介质在非局部的电荷转移状态下氧化了外围的叶绿素颜料.
结论:
- 这项研究挑战了现有的光系统绝缘模型.
- 从光系统中提取早期的电子是可行的.
- 开辟了研究光合作用和半人工光合作用的新途径.
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