ProcMによるランチオニン形成の地域選択性を制御する基板配列
Tung Le1, Kevin Jeanne Dit Fouque2, Miguel Santos-Fernandez2
1Department of Chemistry and Howard Hughes Medical Institute, University of Illinois at Urbana-Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States.
Journal of the American Chemical Society
|November 1, 2021
まとめ
サイアノバクテリアは単一の酵素を使用して,多くの前駆体ペプチドから多様なランチペプチドを作成します. 酵素ではなく基板配列がランチオニンのクロスリンクパターンを決定し,将来の予測モデルを支援します.
科学分野:
- 生物化学
- 分子生物学
- 合成生物学
背景:
- ランチペプチドは,リボソーム合成および翻訳後の改変ペプチド (RiPP) で,安定性および生物活性に不可欠です.
- サイアノバクテリアは,単一のランチオニン合成酵素を用いて,多様な前駆体ペプチドから多数のランチペプチドを生成するユニークな結合生物合成を示している.
- 単一の酵素が多数の基板のサイクルを制御するメカニズムは不明である.
研究 の 目的:
- シアノバクテリアのランチペプチド生物合成におけるランチオニンのクロスリンク地域選択性を支配する要因を調査する.
- ランチペプチド同位体分離のためのトラップされたイオン移動スペクトロメトリ-タンデム質量スペクトロメトリ (TIMS-MS/MS) を評価する.
- 結合生物合成からランチペプチド環のパターンを予測するための基礎を確立する.
主な方法:
- ProcA3.3 前駆ペプチドのバリエーションのライブラリを利用した.
- 捕獲イオン移動スペクトロメトリー-タンデム質量スペクトロメトリー (TIMS-MS/MS) を同位体分離に使用した.
- 分析された基板配列と酵素活性 (ProcM).
主要な成果:
- 亜基質ペプチド配列は,ProcM酵素ではなく,ランチオニン形成の地域選択性を決定する.
- TIMS-MS/MSは,従来の液体クロマトグラフィよりも効率的にランチペプチド構成イソマーを分離しました.
- サイクリング結果の重要な要因を特定したが,すべてのシーケンスに対する単純な予測ルールは見つからなかった.
結論:
- シアノバクテリアのランチペプチドサイクリングは主に基板に依存する.
- TIMS-MS/MSは,複雑なランチペプチド混合物を分析するための貴重なツールです.
- 将来のディープラーニングモデルは,結合生物合成におけるランチペプチド環パターンを予測するために開発することができる.
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