ディクチオスタチンの柔軟性は,溶液およびβ-チューブリン・タキサン結合部位におけるコンフォーマーションを橋渡しする
Ashutosh S Jogalekar1, Krishnan Damodaran, Frederik H Kriel
1Department of Chemistry, Emory University, Atlanta, Georgia 30322, USA.
Journal of the American Chemical Society
|February 9, 2011
まとめ
ディクティオスタチン (DCT) は,さまざまな構造を持つ柔軟な分子であり,以前の構造モデルに挑戦しています. 特定の形状 (Conf-2) は微小管の結合に整合し,その活動に関する新しいモデルを示唆しています.
科学分野:
- 化学生物学 化学生物学とは
- 構造生物学 構造生物学とは
- 分子モデリング
背景:
- ディクティオスタチン (DCT) は,強力なマイクロチューブルポリメリゼーション活性を持つ複雑なポリケチドマクロリドです.
- 以前の研究では,NMRデータに基づくDCTの溶液構造 (2a) と結合モード (Conf-1) を提案した.
研究 の 目的:
- 計算的方法を用いて,異なる溶媒におけるDCTのコンフォメーション的風景を調査する.
- 新しいデータに照らして,提案されたDCTのコンフォームとバインディングモードを再評価する.
主な方法:
- 広範囲にわたる力場に基づく構造調査が行われました.
- 溶液NMRデータからの幾何学的なパラメータが統合されました.
- 分子ドッキング方法 (Glide,Autodock,RosettaLigand) は,DCT/β-チューブリン相互作用をモデル化するために適用されました.
主要な成果:
- この研究は,多種多様なDCT構造を明らかにし,重要な分子柔軟性を示した.
- 以前提案された支配的形状 (2a) は除外された.
- マイクロチューブルの結合に関するTR-NOESY NMRデータと一致する特定の形状 (Conf-2) が特定されました.
- β-チューブリンによるDCTの低エネルギー結合モデル (Pose-2/Conf-2) が成功裏に予測されました.
結論:
- DCTには相当な形状の柔軟性があり,そのソリューション構造の理解を改めることが必要である.
- 特定されたConf-2形状は,DCTが微小管と相互作用する可能性のあるモデルを提供します.
- 予測されたDCT/β-チューブリン複合体の構造は,DCTの新興構造-活動関係データをサポートしています.
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