代替的なグリカン特異性を持つエンドグリコシダゼは,拡大されたグリコタンパク質の改造を可能にします
Jonathan J Goodfellow1, Kavitha Baruah, Keisuke Yamamoto
1Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford OX1 3TA, UK.
Journal of the American Chemical Society
|May 4, 2012
まとめ
新しい細菌のエンドグリコシダゼであるEndoSは,タンパク質グリカン改造の選択性を高めます. この酵素は,複雑なタイプのN結合グリカンを処理し,以前は難しい抗体グリコフォームに対応します.
科学分野:
- バイオケミストリー バイオケミストリー
- グライコバイオロジーは,
- 酵素学 酵素学とは
背景:
- タンパク質エンドグリコシダースは,タンパク質に結合したグリカン (glycans) の生物触媒的改変に不可欠である.
- 既存のエンドグリコシダースの選択性が限られているため,多様なN結合グリカン (N-linked glycans) の操作が困難である.
- 特定のN-リンクされたグリカン構造は,現在の酵素処理方法に対して耐火性である.
研究 の 目的:
- タンパク質グリカン改造に対する選択性が向上した新しいエンドグリコシダースを特定し,特徴づけること.
- バクテリアのエンドグリコシダゼ (EndoS) の補完的な活性,EndoAやEndoHのような既存の酵素と並行して評価する.
- タンパク質,特に抗体に対する,以前は難解なN結合グリカン構造の効果的な操作を可能にする.
主な方法:
- バクテリアのエンドグリコシダゼ (EndoS) を Streptococcus pyogenes.から分離し,特徴づけました.
- EndoS.の基板特異性を決定するバイオカタリティクアッセイ.
- 様々なN結合グリカン基板を使用して,既知のエンドグリコシダゼ (EndoA, EndoH) に対するEndoS活性比較分析.
- EndoSの応用は,コア・フクソシル化を含む,複合型N結合グリカン (N-linked glycans) の加工に用いられる.
主要な成果:
- EndoSは,EndoAとEndoHと異なる,明確な基板特異性を表しています.
- EndoSは,コア・フクソシル化またはそれなしの複合型N結合グリカンを効果的に処理します.
- EndoSは,オリゴマノース型またはハイブリッド型N結合グリカンを処理していません.
- この選択的活動は,酵素によるグリカン改造のためのツールキットを拡張します.
結論:
- バクテリアのエンドグリコシダゼ (EndoS) は,タンパク質グリカン改変のための補完的な酵素活性を提供します.
- EndoSは,耐火性抗体グリコフォームに含まれるものを含む,複合型N結合グリカンの処理を可能にします.
- この発見は,タンパク質工学とグリカン操作の分野を前進させる.
関連する概念動画
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