不飽和グルキュロニルヒドロレーゼスにおける新しいメカニズムによるグリコシド分裂
Seino A K Jongkees1, Stephen G Withers
1Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia, Canada V6T 1Z1.
Journal of the American Chemical Society
|November 4, 2011
まとめ
不飽和グルキュロニル水溶解剤 (UGL) は,古典的な水溶解剤とは異なる,新種のビニルエーテル水分化メカニズムを使用して,グリコシド結合の分裂を行う. この経路は,細菌感染症において極めて重要であり,新たな治療標的を提供している.
科学分野:
- バイオケミストリー バイオケミストリー
- 酵素学 酵素学とは
- グライコバイオロジーは,
背景:
- 不飽和グルキュロニルヒドロラーゼ (UGL) は,グリコシドヒドロラーゼ (GH) 家族88の酵素である.
- 彼らは,細菌のポリサッカリドライアゼによって生成されたオリゴサッカリドから不飽和糖を分離します.
- このプロセスは細胞外細菌感染症において不可欠であり,哺乳類に類似するものはない.
研究 の 目的:
- UGLアクションの提案された新しいメカニズムの明確な証拠を提供するために.
- UGLの触媒メカニズム,特に提案されたビニルエーサー水分化の経路を調査する.
- UGLメカニズムを古典的なヒドロラーゼメカニズムと区別するために.
主な方法:
- H2O,D2O,および希釈メタノール/水におけるUGL触媒反応の製品分析.
- ティオグリコシドおよび逆アノメリック構成のグリコシドに対するUGL活性検査.
- C-グリコシドアナログのUGL触媒化水分化を評価する.
- β-二次運動同位体効果を測定する.
主要な成果:
- UGLは,ビニルエーテル群の水分化を触媒化し,グリコシド結合の割れにつながることが示されました.
- ティオグリコシドなどの古典的なグリコシダゼに耐性のある基質は,UGLによって急速に裂けられた.
- C-グリコシドのアナログは水素化を施し,水素化が誘発するメカニズムをサポートした.
- 小さなβ二次運動同位体効果は,オキシカルベニウムイオンの移行状態を示した.
結論:
- この研究は,UGLsのための新しいビニルエーテル水分化メカニズムを検証しています.
- このメカニズムは,アノメリック炭素における直接ヒドロラーゼメカニズムの逆転または保持とは異なる.
- この発見は,バクテリアの病原性におけるUGLの機能のより深い理解を提供します.
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