ラパミシン遺伝子群にコード化されたライシンサイクロデアミナーゼであるRapLによるパイプコリック酸のバイオシンセシス
Gregory J Gatto1, Michael T Boyne, Neil L Kelleher
1Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA.
Journal of the American Chemical Society
|March 16, 2006
まとめ
この研究は,RapL酵素の有効性を検証しています.
科学分野:
- バイオケミストリー バイオケミストリー
- 自然製品バイオシンセシス 自然製品バイオシンセシス
- 酵素学 酵素学とは
背景:
- ラパミシン,FK506,FK520は重要な免疫抑制剤である.
- これらのマクロラクトン天然製品は,パイプコリック酸の残留物を含んでいます.
- ピペコリック酸は,ライシンサイクロデアミネーションによって生物合成されます.
研究 の 目的:
- パイプコリック酸の生物合成におけるRapL酵素の機能を調査する.
- ライシンサイクロデアミナ化の触媒機構を特徴づけるために.
- ライシンサイクロデアミナーゼの初のインビトロ特徴を明らかにする.
主な方法:
- RapL酵素の異質的な過剰発現と浄化.
- L-リジンとL-オルニチンを基質として使用した酵素分析.
- 機械的な詳細を確認するために,同位体でラベル付けされた基板.
- コファクター要件を決定するスペクトル分析.
主要な成果:
- RapLは,L-リジンをサイクロデアミネーションによってL-ピペコリック酸に成功的に変換します.
- この反応は,ニコチナミドアデニン・ディヌクレオチド (NAD+) との酸化還元触媒反応を伴う.
- RapLはL-オルニチンと比べて効率が低く,最適な活動のためにNAD+を必要とします.
- 機械学的な研究では,アミンの損失とアルファ炭素の水素保持が確認されました.
結論:
- RapLは,重要な免疫抑制剤の生物合成における重要な酵素である.
- この研究は,ライシンサイクロデアミネーションのメカニズムを明らかにしています.
- この研究は,このユニークな酵素変換におけるNAD+の役割を強調しています.
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