プラズモディアム・ファルシパラムとヒトオロタート・フォスフォリボシルトランスフェラーゼの移行状態
Yong Zhang1, Minkui Luo, Vern L Schramm
1Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York 10461, USA.
Journal of the American Chemical Society
|March 19, 2009
まとめ
プラズモディアム・ファルシパラムとヒトからのオロテート・フォスフォリボシルトランスフェラーゼ (OPRT) は,新しい抗マラリアおよび抗癌薬の開発のために研究されました. 計算分析により,それらの移行状態構造が明らかになり,新しい阻害剤の設計に役立ちました.
科学分野:
- バイオケミストリー バイオケミストリー
- 薬用化学 薬用化学について
- 寄生虫学とは,寄生虫学である.
背景:
- オロ酸塩酸化ボシルトランスフェラーゼ (OPRT) は,新型ピリミジン生物合成における重要な酵素である.
- PfOPRTは,Plasmodium falciparumの生存に不可欠であり,抗マラリア薬の標的となっています.
- HsOPRTは,がんや自己免疫疾患に関与しており,治療目標である.
研究 の 目的:
- プラズモジアム・ファルシパラム OPRT (PfOPRT) とヒト OPRT (HsOPRT) の移行状態構造を解明する.
- 抗マラリアおよび抗癌療法のための新しいOPRT阻害剤の設計のための洞察を提供するために.
主な方法:
- キネティック・イソトープ効果 (Kinetic Isotope Effects, KIE) は,様々なイソトープを用いて,リン酸酸 (Phosphonoacetic Acid, PA) に対して測定された.
- 移行状態の構造を決定するために,計算化学の方法が採用されました.
- 基板特異性および阻害研究が行われました.
主要な成果:
- PfOPRTとHsOPRTの内在的なKIEsを決定し,明確なパターンを明らかにしました.
- KIEsによる計算モデリングにより,両酵素の遅いアソシエティブD ((N) *A ((N) (((ダブルダガー) 移行状態が特定されました.
- 移行状態では,リボシル2'-C-endo構成が示された.
結論:
- この研究では,PfOPRTとHsOPRTの移行状態構造を特徴づけました.
- これらの構造を理解することで,OPRT標的薬の合理的な設計が容易になります.
- p-ニトロフェニルβ-D-リボース5'-リン酸は,被験者の反応座標を検証し,阻害剤としての可能性を示している.
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