非正規的なSAM分裂とC-As結合形成のためのラジカルSAM酵素を含むアルシノトリシン生物合成
Yadi Yao1, Jiale He1, Fan Chen1
1Frontiers Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China.
Journal of the American Chemical Society
|July 25, 2024
まとめ
アルシノトリシン抗生物質のバイオシンセシスは,炭素とアルゼンチンの結合を形成するユニークな SAM酵素である ArsL を含む. この研究は,ArsL
科学分野:
- 生物化学
- 酵素学
- 微生物学
背景:
- アルシノトリシンは,土壌細菌によって作られる強力な抗生物質です.
- その生物合成には,タンパク質ArsLによって触媒化された炭素-ヒ素結合の形成が含まれます.
- ArsLにはCxxxCxxCモチーフが含まれており,これはSAM酵素の特徴です.
研究 の 目的:
- アルシノトリシン生物合成におけるSAM酵素ArsLの機能とメカニズムを特徴づける.
- 他のSAM酵素と比較して,ArsLのユニークな特徴を調査する.
- アルシノトリシン生物合成を in vitro で再構成する.
主な方法:
- S-アデノシル-l-メチオニン (SAM) に対するArsLの分裂活性を決定する酵素測定.
- ArsLの重要な機能的モチーフを特定するためのサイト指向型変異と断片化研究.
- ArsLとArsMを用いたアルシノトリシン生物合成の in vitro 再構成
主要な成果:
- ArsLはCxxxCxxCモチーフのSAM酵素の非正規反応である3-アミノ-3-カルボキシプロピル (ACP) を生成するためにSAMを割ります.
- ArsLの保存されたRCCLKCモチーフは,アルセニット結合と酵素活性に不可欠です.
- アルシノトリシン生物合成はArsLとArsMで in vitroで成功裏に再構成されました.
結論:
- ArsLは独特のSAM酵素であり,正規のモチーフを示しているが,正規でない反応を触媒化している.
- この発見は,この酵素スーパーファミリー内の未発見の非正規のSAM化学の可能性を示唆しています.
- この研究では,アルシノトリシン生物合成の詳細なメカニズムが示されています.
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