アリファティック・エーテル・ボンド形成は,天然製品生物合成におけるラジカルSAM酵素の範囲を拡大する
Kenzie A Clark1, Leah B Bushin1, Mohammad R Seyedsayamdost1,2
1Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States.
Journal of the American Chemical Society
|June 28, 2019
まとめ
研究者らは,リボソーム合成および翻訳後の改変ペプチド (RiPP) で初めてエーテルクロスリンクを生成する新しい酵素を発見した. この発見により 微生物の天然産物生物合成と 酵素触媒の理解が広がりました
科学分野:
- 生物化学
- 分子生物学
- バイオ情報学
背景:
- 微生物の天然製品は新しい酵素変換の貴重な源である.
- リボソームで合成されたペプチドと翻訳後のペプチド (RiPP) は,多様な自然産物である.
- ラジカルS-アデノシルメチオニン (RaS) 酵素は独特の生化学反応を触媒化する.
研究 の 目的:
- 新しい生物情報検索戦略によって特定された新しいRaS酵素を特徴づける.
- RiPP遺伝子クラスター内のRaS酵素の触媒的活性を調べる
- 新しい RiPP 改変経路とヘテロサイクリング モチーフを探求する.
主な方法:
- RaS金属酵素を含むRiPP遺伝子クラスタを特定するためのバイオ情報分析.
- 特定のRaS酵素の生化学的特徴
- 結果の翻訳後の修正とヘテロサイクリングの分析.
主要な成果:
- クオラムセンシングで調節されるRaS酵素による多数のRiPP遺伝子クラスタの識別.
- ThrとGlnの残留物間のアリファティックエーテルクロスリンクを形成するRaS酵素の特徴.
- これは,新しいヘテロサイクリングモチーフを形成する,RaS酵素によって触媒化されたエーテルクロスリンクの最初の例を表しています.
結論:
- この研究は,RiPPのバイオシンセシスにおける新しいRaS酵素触媒エーテルクロスリンク反応を明らかにした.
- この発見は,天然製品における 酵素的変化の既知のレパートリーを拡張します.
- バイオインフォマティクスのアプローチは,新しい RiPP 改変ファミリーの発見に有効です.
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