電化学的に駆動された光合成電子輸送 サイアノバクテリアの光学系II欠乏
Christine M Lewis1,2,3, Justin D Flory2,4, Thomas A Moore1,5
1School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, United States.
Journal of the American Chemical Society
|February 14, 2022
まとめ
新しい微生物電気光合成システム (MEPS) は,損傷した光システムII (PSII) をバイパスして,電極を使用して光合成を推進します. このシステムは,エネルギー生産のための電子輸送を強化し,光合成効率の向上の可能性を提供します.
科学分野:
- 生物化学
- 光合成の研究
- バイオエネルギー
背景:
- 光学系II (PSII) は光合成における水の分裂に不可欠であるが,光による損傷に弱い.
- 光合成の電子輸送を推進するための代替方法の開発は,光合成を理解し改善するために不可欠です.
研究 の 目的:
- 機能的なPSIIを欠くシネコシスティス細胞の電子輸送を駆動するための新しい微生物の電気光合成システム (MEPS) を調査する.
- MEPSにおける光依存電子伝送の効率と特性を評価する.
主な方法:
- 微生物の電気光合成システム (MEPS) を利用し,レドックスメディエーターと電極を用い, *シネコシスティス* (Δ*psbB*) 細胞で電子輸送を推進した.
- 光に依存した電流生成とP700+再還元運動を測定した.
- 電子配送速度と電流密度を定量化した.
主要な成果:
- MEPSは光に依存する電流を生成し 光の強さに伴い増加した.
- 電子配送率は113μmol電子h−1 mg-chl−1で,2050μmol光子m−2 s−1に達した.
- 初期電子配送率は,NADPHとATPの生成をサポートするサイトクローム*b*6*f*複合体より前に発生するワイルドタイプPSIIによって引き起こされるものを上回った.
結論:
- MEPSはPSII欠乏細胞で 光合成電子輸送を成功させる.
- このシステムは,基本的な光合成の研究のプラットフォームとして機能します.
- MEPSは高光条件下での光合成性能の向上の可能性を示しています.
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