プロファージ切除は,ファゴソームの脱出と毒性を促進するリステリアの能力遺伝子を活性化させます
Lev Rabinovich1, Nadejda Sigal, Ilya Borovok
1Department of Molecular Microbiology and Biotechnology, Tel Aviv University, Tel Aviv 69978, Israel.
Cell
|August 21, 2012
まとめ
以前は機能しないと考えられていたListeria monocytogenes Competence (Com) システムは,感染中に宿主細胞からバクテリアの脱出に不可欠です. プロファージは遺伝子スイッチとして機能し,DNAの変形なしにCOMシステムの機能を可能にします.
科学分野:
- 微生物学 微生物学とは
- バクテリア病原菌の発生
- 分子生物学は分子生物学である.
背景:
- *Listeria monocytogenes*の能力 (Com) システムは,プロファージによるマスターレギュレータ遺伝子 (comK) の障害により,広く非機能性と考えられています.
- この病原体においてDNA変異の条件は特定されていない.
研究 の 目的:
- 宿主感染中のListeria monocytogenes* Comシステムの役割を調査する.
- プロファージとcomK遺伝子を関わる規制メカニズムを解明する.
主な方法:
- 細胞内細菌の成長中のComシステムの機能の分析.
- プロファージ切除の調査と,comK遺伝子の完全性への影響.
- マクロファージファゴソームからのバクテリアの脱出の評価.
主要な成果:
- コムシステムは,Listeria monocytogenesが感染中にマクロファージファゴソームから脱出するために不可欠であり,DNAの吸収とは無関係です.
- 細胞内成長中に誘発されたプロファージ切除は,機能的なcomK遺伝子を復元します.
- プロファージ切除は,感染性ウイルス粒子の生成なしに起こり,特定の遺伝子スイッチとして作用します.
結論:
- *Listeria monocytogenes* Comシステムは,DNA変換に関与しない活性毒性因子です.
- 温和プロファージは,条件付き遺伝スイッチとして作用し,comK遺伝子発現を制御することによって,感染中に細菌の毒性を調節します.
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