溶液と生物学的関連型は,エナティオメリック11-cis-lockedサイクロプロピルレチナルスの溶液と生物学的関連型です
Yukari Fujimoto1, Nathan Fishkin, Gennaro Pescitelli
1Department of Chemistry, Columbia University, New York, New York 10027, USA.
Journal of the American Chemical Society
|June 20, 2002
まとめ
研究者は,牛のオプシンにおける11-cis-レチニリデンの染色体を,新しい双循環性網膜類似体を用いて研究した. オプシンと結合するのはベータ・サイクロピルエナティオメール (2a) だけであり,染色体結合と受容体内の構成に関する洞察を示している.
科学分野:
- バイオケミストリー バイオケミストリー
- 分子生物学は分子生物学である.
- スペクトル顕微鏡検査です.
背景:
- 牛のオプシンにおける11-cis-レチニリデンの染色体の構成を理解することは,視覚的色素の機能にとって極めて重要です.
- ポリエネシステムに関連したキラル・サイクロプロピル群は,カイロプティックへの貢献がよく理解されていない.
研究 の 目的:
- オプシン.に結合した11-cis-ロックされたビサイクロ[5.1.0]オクチル網膜 (retCPr) の形状を調査する.
- ポリエネシステムに付着したサイクロプロピルリングのカイロプティックへの貢献を明確にするために.
- retCPrエナントイオマーのオプシンへの結合選択性を決定する.
主な方法:
- エナティオメリック11-cis-ロックされたビサイクロ[5.1.0]オクチル網膜 (retCPr) の合成と特徴付け.
- リングの形状を決定する核磁気共鳴 (NMR) スペクトロスコーピー.
- 構造をモデル化するための計算方法 (幾何学最適化,CD計算)
- オプシン結合測定法で,エナティオメルの選択性を評価する.
主要な成果:
- NMRは, retCPrの7つ構成のリングのツイストチェア構造を明らかにした.
- 計算分析により,エナティオマー2aはC12-C13の周りの正の回転を持つダイアステレオマーとして存在することを示した.
- オプシンと結合するのはβ-cyclopropylエナチオメール (2a) だけで,α-エナチオメール (2b) は結合しません.
- サイクロプロピル部分の染色体への結合効果は最小限である.
結論:
- 染色体はオプシンのN端に結合し,4メチレンおよび15アルデヒド側から入ります.
- オプシンの結合裂けは,C12-C13の周りのわずかな正の回転で11-cis-レチナルを収容しています.
- この形状は,retCPr 2aの観察されたバイオステレオ選択性を説明し,以前の光学データを再解釈します.
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