プロミスキュアス・ランチペプチド・シンセテーゼProcMによる製品形成は,運動制御下にある
Yi Yu1, Subha Mukherjee1, Wilfred A van der Donk1
1†Department of Biochemistry, ‡Department of Chemistry, and §Howard Hughes Medical Institute, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave. Urbana, Illinois 61801, United States.
Journal of the American Chemical Society
|March 25, 2015
まとめ
ランチペプチド合成酵素ProcMは高い製品選択性を示しており,その変異はサイクル化率と地域選択性に影響する. 初期環形成は,熱力学的制御ではなく,最終製品のトポロジーを決定する.
科学分野:
- バイオケミストリー バイオケミストリー
- 分子生物学は分子生物学である.
- 自然製品 化学 化学
背景:
- ランチペプチドは,様々な生物学的活動を持つリボソーム合成および翻訳後の改変ペプチド (RiPP) です.
- 主な構造的特徴には,ランチオニン (Lan) またはメチランチオニン (MeLan) ブリッジが含まれています.
- ランチペプチド合成酵素ProcMは,広範囲の基板耐性を示すが,高い製品選択性を示している.
研究 の 目的:
- ProcMによるランチペプチド合成における地域選択性のメカニズムを調査する.
- 製品形成における活性部位残留と初期サイクリングイベントの役割を決定する.
- 変異がサイクライゼーション率と製品トポロジーに及ぼす影響を調査する.
主な方法:
- ProcM活性部位残留 (亜鉛リガンド) のサイト指向型変異.
- 特定のランチペプチド基板 (ProcA1.1,ProcA2.8,ProcA3.3) を使用したサイクリング率と製品形成の分析.
- 反応産物の特徴化により,地域選択性と環形トポロジーを評価する.
主要な成果:
- アクティブサイト亜鉛リガンドの変異により,特に第2回サイクルステップにおいて,サイクライゼーション率が低下した.
- 特定の突然変異は,基板ProcA3.3のサイクライゼーションの地域選択性を変化させ,新しい主要な製品を生み出しました.
- ProcMは,誤ってサイクルされた中間物質を修正できず,熱力学的制御の欠如を示しています.
結論:
- ProcMによるランチペプチド形成の高い地域選択性は,主に最初のリング形成の選択性によって決定されます.
- 活性部位に影響する突然変異は,反応動力学と製品特異性の両方に影響を及ぼします.
- ランチペプチドのバイオシンセシスは運動的に制御され,初期のサイクライゼーションイベントが全体の製品構造を指示します.
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