ATP結合とアスパルテートプロトネーションは,植物クリプトクロームにおける光誘発電子移転を強化する
Fabien Cailliez1, Pavel Müller, Michaël Gallois
1Laboratoire de Chimie Physique, UMR 8000, Université Paris-Sud and CNRS , Orsay F-91405, France.
Journal of the American Chemical Society
|August 27, 2014
まとめ
ATP結合とpHは,暗号クロームに影響を及ぼします.
科学分野:
- バイオケミストリー バイオケミストリー
- 写真生物学 写真生物学
- 分子生物学は分子生物学である.
背景:
- クリプトクロームは,植物や動物の青光受容体である.
- 彼らの機能には,フラボプロテインFADコファクターが含まれています.
- 光によって誘発されるFADの減少は,過激な状態につながります.
研究 の 目的:
- クリプトクローム光還元に対するATPとpHの影響の分子メカニズムを分析する.
- ATP結合とD396陽子化状態がFADH°形成をどのように調節するかを調査する.
主な方法:
- 組み合わせた古典的分子動力学 (MD) シミュレーション.
- 時間依存密度関数理論 (TD-DFT) の計算.
主要な成果:
- ATPと陽子化されたD396は,FAD-W400と密接な接触を維持し,電子伝送 (ET) を強化します.
- D396のデプロトン化とATPの欠如はFAD-W400距離を増加させ,ET率を低下させます.
- FADのアデニン部分からのETは,これらの条件下で競争力のある経路になります.
結論:
- FADの光還元に対するATPとpHの影響は,初期段階から生じます.
- ATP結合とD396陽子化状態は,イソオロキサジン環の主要なリラックス経路を決定する.
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