遺伝子組み換え脂肪酸サイドチェーンを持つ非リボソーム性リポペプチドの合成生物合成
Amanda Powell1, Mathew Borg, Bagher Amir-Heidari
1School of Chemistry, The University of Manchester, Oxford Road, Manchester, United Kingdom.
Journal of the American Chemical Society
|November 21, 2007
まとめ
カルシウム依存抗生物質 (CDAs) の活動は,それらの脂肪酸鎖と関連しています. 研究者はCDAのバイオシンセシスを改変して,変化した脂肪酸群を持つ新しいリポペプチドを作り,抗生物質の性質を保持しました.
科学分野:
- バイオケミストリー バイオケミストリー
- 微生物学 微生物学とは
- 合成生物学 合成生物学とは
背景:
- ダプトマイシンのようなカルシウム依存抗生物質 (CDA) は,非リボソーム性リポペプチドである.
- 彼らの生物学的活動は,N端の脂肪酸によって著しく影響を受けます.
- 生物合成経路とCDA脂肪酸鎖の長さの酵素制御は完全に理解されていません.
研究 の 目的:
- CDA脂肪酸鎖の長さを決定する際に,KAS-II酵素 (fabF3で符号化) とHxcOの役割を調査する.
- 修飾された脂肪酸分子を用いて新しいCDAを生成する可能性を調査する.
- 変化したN末端脂肪酸鎖を持つCDAの抗生物質活性を評価する.
主な方法:
- CDA製品の変化を観察するための遺伝子消去研究 (hxcO).
- 脂肪酸鎖の長さを決定するためにリポペプチド製品の分析.
- CdaPS1.1のサイト指向型変異を伴うミュータシンセシスアプローチ.
- 合成N-アシル-L-セリニルN-アセチルシステアミン (NAC) のチオエステル類の組み込み.
主要な成果:
- hxcOの削除により,ヘクサノイルを含むCDA (hCDA) が生成され,HxcOの酸化酵素としての役割が確認されました.
- 証拠によると,CDA脂質鎖のバイオシンセシスは,CdaPS1.1に転送される前に,単一のACPで発生する.
- ヘクサノイルを含むCDAは,重要な抗生物質活性を維持しました.
- ミュタシンセシスは,ペンタノイルとヘクサノイルサイドチェーンを持つCDAの生成を可能にしました.
結論:
- HxcOは,CDAにおける特定の短い脂肪酸鎖の生成に不可欠である.
- CDAの生物合成経路は,単一のACPとCdaPS1への直接転送を含みます.
- ミュタシンセシスによるN端脂肪酸群の改変は,抗生物質活性が保持された新しいCDAを生成するための実行可能な戦略です.
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