Fe (II) 依存ハロゲナーゼとサイクロプロパンを形成するフラボプロテインによる (-) - 1S,2R) -アルコロナミックアシルチオエステルの生物合成
Christopher S Neumann1, Christopher T Walsh
1Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA.
Journal of the American Chemical Society
|October 3, 2008
まとめ
研究者らは,4タンパク質のKtzABCDシステムを用いて,新しい非タンパク質原性アミノ酸 (1S,2R) -アロコロナミク酸の生物合成を解明した. この発見は,新しいペプチド改変の道を開く.
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.
- 自然製品のバイオシンセシス
背景:
- ヘキサペプチドラクトンのクツネリド族は,ユニークな非タンパク質性アミノ酸を含んでいます.
- KtzABCD遺伝子クラスターは,これらの異常なアミノ酸の合成を担当することが提案されています.
研究 の 目的:
- KtzABCDシステムを in vitro で再構成し,最終製品を特定するために.
- 非タンパク質原性アミノ酸の生物合成経路を解明する.
主な方法:
- 4タンパク質のKtzABCDシステムの in vitro 再構成.
- 生化学分析により,製品を特定し,酵素機構を特徴づけます.
主要な成果:
- 4つのタンパク質系が成功裏に再構成され, (1S,2R) -アロコロナミク酸が得られました.
- 酵素KtzD (ハロゲナーゼ) とKtzA (アシル-CoA脱水素酵素のようなタンパク質) は,ガンマ-クロロアイソルユキル中間体の形成と循環を媒介することが示されました.
- 最終製品は,チオエステル結合によってキャリアタンパク質KtzCに結合し,KtzAはフラビン共因子による酸化還元活性なしに機能します.
結論:
- 新しいモノマーである (1S,2R) - アロコロナミク酸が特定され,そのユニークな生物合成経路が明らかにされました.
- この経路には,非ヘムFe (II) 依存ハロゲナーゼとアシル-CoA脱水素酵素のようなタンパク質が含まれています.
- この発見は,非リボソームペプチドに潜在的に組み込むための新しい構成要素を導入しています.
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