ランチペプチド生物合成における部分改変ペプチド中間物質は,ランチペプチド合成酵素の構造とダイナミクスを変化させる
Yeganeh Habibi1, Nuwani W Weerasinghe1, Kevin A Uggowitzer1
1Department of Chemistry, McGill University, 801 Sherbrooke St. West, Montreal, Quebec H3A 0B8, Canada.
Journal of the American Chemical Society
|June 1, 2022
まとめ
クラスIIランチペプチド合成酵素 (LanM酵素) は,前駆体ペプチドを複合的な天然製品に改造する. この研究では,前駆体ペプチドの改変が,ハルM2酵素の構造と動態を体系的に変化させ,高信頼性の生物合成を保証する方法を明らかにした.
科学分野:
- 生物化学
- 分子生物学
- 自然製品合成
背景:
- ランチペプチド合成酵素は,翻訳後の改変によってマクロサイクリックペプチドの天然産物を生成するために不可欠である.
- クラスIIのランチペプチド合成酵素 (LanM酵素) は,基板の柔軟性を示すが,依然として理解されていないメカニズムである高い生物合成フィデリティを達成する.
研究 の 目的:
- 熟成先駆体ランチペプチド (HalA2) の構造が,その同類のランチペプチド合成酵素 (HalM2) の構造と動態にどのように影響を与えるかを調査する.
- クラスIIランチペプチド生物合成の高信頼性の基礎となるメカニズム的な詳細を解明する.
主な方法:
- 本来のチオエーテルマクロサイクルによるHalA2ペプチドの酵素合成.
- イオン移動質量スペクトロメトリー (IM-MS) で,HalM2の構成変化を分析する.
- 局所的なHalM2構造ダイナミクスを研究するための水素-デュテリウム交換質量スペクトロメトリ (HDX-MS).
主要な成果:
- ハルA2マクロサイクリングは,ハルM2酵素の全体的な形状を体系的に変化させる.
- 翻訳後のハルA2への反応として,HalM2の局所的な構造的動態の変化.
- ハルM2α-ヘリカル領域におけるデウテリウム吸収は,ハルA2内のチオエーテルマクロサイクルの数に依存する.
- HalA2の明確なリーダーとコアペプチド結合部位は,HalM2の機能的に重要なα-ヘリクスの構造に相乗効果を発揮する.
結論:
- HalA2の連続的な翻訳後の改変は,HalM2の構成動態を変えます.
- これらのダイナミックな変化は,酵素の機能的に重要な領域と関連しています.
- この発見は,前駆体ペプチド構造が高精度生物合成のための酵素動態を決定するモデルを支持する.
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