ロドプシンにおけるオプシンシフト:タンパク質,溶液,ガス相における網膜S0-S1刺激
Ksenia Bravaya1, Anastasia Bochenkova, Alexander Granovsky
1Department of Chemistry, M.V. Lomonosov Moscow State University, 1/3, Leninskie Gory, Moscow 119992, Russian Federation.
Journal of the American Chemical Society
|October 11, 2007
まとめ
コンピューティングモデルは,さまざまな環境における11-cis網膜光吸収スペクトルを正確に予測します. スペクトルに影響を与える重要な要因には,染色体幾何学とタンパク質の相互作用が含まれ,これは視覚的プロセスを理解するのに不可欠です.
科学分野:
- 計算化学はコンピュータ化学である.
- フォトケミストリー フォトケミストリー
- バイオフィジックス 生物物理学
背景:
- 11-cis網膜は,視力の重要な染色体である.
- その光吸収を理解することは,視覚の色素の機能に不可欠です.
研究 の 目的:
- 11-cis網膜の光吸収をモデル化し分析する.
- 異なる環境 (ガス,溶液,タンパク質) がそのスペクトルに及ぼす影響を調査する.
主な方法:
- 量子力学-分子力学 (QM/MM) アプローチ.
- Augmented multiconfigurational quasidegenerate perturbation theory (aug-MCQDPT2) は,拡張された多構成型準退化性波動理論 (aug-MCQDPT2) と呼ばれています.この理論は,アグメントされた多構成型準退化性波動理論 (aug-MCQDPT2) と呼ばれています.
- 密度関数理論 (DFT) PBE0/cc-pVDZの幾何学最適化について.
主要な成果:
- 計算された吸収帯は,ガス,溶液,タンパク質の環境における実験データと一致します.
- Glu181.1.によるタンパク質における非平面の染色体幾何学が特定されました.
- タンパク質フィールドは,刺激時にC11-C12結合順に大きく影響する.
結論:
- 計算モデルでは,実験的な光吸収スペクトルを正確に再現しています.
- 染色体幾何学,静電場,カウンテリオンがスペクトル特性の決定的な要素である.
- タンパク質の環境,特に有電荷の残基は,非平面性を決定し,光イソメリゼーションの特異性を影響する.
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