皮質細胞表面は,バクテリアの粘着と侵入のために必要なサルモネラタンパク質を誘導します
B B Finlay1, F Heffron, S Falkow
1Department of Medical Microbiology, Stanford University School of Medicine, CA 94305.
まとめ
サルモネラ菌の侵入には,バクテリアによって合成される新しい細菌タンパク質が必要です. これらのタンパク質は,サルモネラ菌の粘着,宿主細胞の侵入,およびマウスの毒性にとって不可欠です.
科学分野:
- 微生物学 微生物学とは
- 細胞生物学 細胞生物学
- バクテリア病原菌の発生
背景:
- サルモネラ菌は,真核細胞内に侵入して複製することが知られている.
- バクテリアの粘着と侵入は,サルモネラ菌感染症の病原性における重要なステップです.
研究 の 目的:
- サルモネラが上皮細胞に粘着し,侵入するために必要な細菌因子を調査する.
- サルモネラ菌の毒性における新たに合成された細菌タンパク質の役割を決定する.
主な方法:
- サルモネラ・コレラエススとサルモネラ・タイフィムリウム菌株を使用した.
- 特定のタンパク質合成に欠陥のある細菌変異体を生成し,分析した.
- バクテリアの粘着と真核細胞の侵入を評価した.
- ネズミのモデルで細菌の毒性を評価した.
主要な成果:
- S. choleraesuisとS. typhimuriumによる表皮細胞の安定した粘着と侵入は,特定の細菌のタンパク質の de novo 合成を必要とします.
- このタンパク質合成は誘導可能なイベントであり,トリプシンとニューラミニダゼに敏感な宿主細胞表面構造によって調節されます.
- これらのタンパク質を合成できない変異体は,結合能力と侵入能力が低下した.
- これらのタンパク質を欠いたS. typhimuriumの変異体2種は,マウスでアビルーランスであった.
結論:
- 特定の細菌のタンパク質の新たな合成は,サルモネラ菌が宿主細胞に固執し,侵入し,感染を確立する能力にとって極めて重要です.
- これらの細菌のタンパク質は,サルモネラ菌にとって不可欠な毒性の要因です.
- この発見は,細菌のタンパク質合成と宿主細胞表面の相互作用を含む調整された規制システムを強調しています.
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