TLR13は,エリトロマイシン耐性形成変異を欠いている細菌の23S rRNAを認識します
Marina Oldenburg1, Anne Krüger, Ruth Ferstl
1Institute of Medical Microbiology, University of Duisburg-Essen, Essen, Germany.
まとめ
マウスは,MLS抗生物質の標的である細菌23SリボソームRNA (rRNA) を認識するトール型受容体13 (TLR13) を有している. バクテリアの抗生物質耐性メカニズムは,この重要な免疫認識を回避することができます.
科学分野:
- 免疫学 免疫学とは
- 微生物学 微生物学とは
- 分子生物学は分子生物学である.
背景:
- 生まれつきの免疫は,病原菌を検出するために,トール型受容体 (TLRs) のようなパターン認識受容体 (PRRs) に依存しています.
- トール型受容体13 (TLR13) は,未知の天然リガンドを持つ孤児受容体である.
研究 の 目的:
- ネズミのトール型受容体13 (TLR13) の天然リガンドを特定する.
- 細菌の成分を認識するTLR13の役割と,抗生物質耐性メカニズムによる脱出を調査する.
主な方法:
- 合成オリゴリボヌクレオチドとバクテリア23SリボソームRNA (rRNA) を用いた刺激アッセイ.
- 抗生物質耐性菌株のrRNAに対するTLR13の反応を検査する.
- 抗生物質耐性を模倣する改変されたrRNAによるTLR13活性化の分析.
主要な成果:
- TLR13は,細菌の23SリボソームRNA (rRNA) の内にある特定の保存された配列を認識します.
- この23S rRNA配列は,マクロリド,リンコサミド,およびストレプトグラムリン (MLS) 抗生物質の結合部位である.
- エリトロミシン耐性黄金球菌23S rRNAと改変されたrRNAはTLR13を活性化できず,免疫逃避を示唆した.
結論:
- バクテリアの23S rRNAはマウスTLR13.3の天然リガンドである.
- バクテリアの抗生物質耐性メカニズム,特に23S rRNAの改変は,TLR13.13経由で宿主の免疫検出を回避する戦略として機能します.
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