非タンパク質原性アミノ酸を含むランチビオティック類のインビトロ変異合成
Matthew R Levengood1, Patrick J Knerr, Trent J Oman
1Howard Hughes Medical Institute and Roger Adams Laboratory, Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA.
Journal of the American Chemical Society
|August 7, 2009
まとめ
研究者らは,非タンパク質原性アミノ酸を用いて,新しいランチビオティック類型を作り出した. 2つの類似品であるTrp19NalとPhe23hPheは,Lactococcus lactis HP.に対する抗菌性の強化を示した.
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:
- ランチバイオティクスは,リボソームで合成されたペプチド抗生物質です.
- ランチオニンやメチランチオニンなどのチオエーテルクロスリンクが特徴です.
- 以前に,非タンパク質原性アミノ酸とのランチビオティック類は報告されていない.
研究 の 目的:
- 新型ラクチシン481の類似体を生成し,特徴づけること.
- 非タンパク質原性アミノ酸がランチビオティック活性に与える影響を調査する.
- 改善された抗微生物特性を持つラクチシン481の類似体を特定する.
主な方法:
- 乳チキン481合成酵素のインビトロ溶解.
- 非タンパク質原性アミノ酸によるペプチド基板の合成.
- アガール拡散測定と最小抑制濃度 (MIC) 試験.
主要な成果:
- ノンプロテオゲン系アミノ酸を用いて,ラクチシン481の類似体11種が成功裏に合成されました.
- Trp19NalとPhe23hPheの類型は,親化合物よりも大きな阻害ゾーンを示した.
- この2つの類似品は,Lactococcus lactis HP.に対するMIC値の改善も示した.
結論:
- 非タンパク質性アミノ酸は,ランチビオティックに組み込まれ,同類を作ることができます.
- Trp19NalやPhe23hPheなどの特殊な置換物は,抗菌剤の効力を強化する.
- この研究は,新しいランチビオティックベースの抗菌剤の開発への道を開きます.
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