CRISPR/Casバクテリア免疫システムは,バクテリオファージとプラズミドDNAを分割する
Josiane E Garneau1, Marie-Ève Dupuis, Manuela Villion
1Département de biochimie, de microbiologie et de bio-informatique, Faculté des sciences et de génie, Groupe de recherche en écologie buccale, Faculté de médecine dentaire, Félix d'Hérelle Reference Center for Bacterial Viruses, Université Laval, Quebec City, Quebec G1V 0A6, Canada.
Nature
|November 5, 2010
まとめ
ストレプトコッカス・サーモフィルス (Streptococcus thermophilus) のCRISPR1/Cas系は,プラズミドからスペーサーを取得することができ,プラズミドの喪失につながり,抗生物質耐性遺伝子に対する免疫を提供します. この細菌の免疫システムは,侵入したDNAを素早く分割します.
科学分野:
- 微生物学 微生物学とは
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
背景:
- バクテリアとアルカイアには,外来核酸に対する防御メカニズムがあります.
- クラスタ化された規則的に間隔のある短いパリンドロミックリピート (CRISPR) /CRISPR関連 (Cas) システムは,シーケンス固有の免疫を提供します.
- CRISPRシステムは,外来DNAからスペーサーを取得し,その後の侵入を認識し,中和します.
研究 の 目的:
- ストレプトコッカス・サーモフィルス (Streptococcus thermophilus) のCRISPR1/Cas系が自己複製性プラズミドからスペーサーを取得できるかどうかを調査する.
- プラズミドの喪失と細菌の免疫における得られたスペーサーの役割を決定する.
- CRISPR1/CasシステムのDNA分裂メカニズムについて,in vivoの証拠を提供するためです.
主な方法:
- CRISPR1/Casシステムによる抗生物質耐性遺伝子を含むプラズミドからスペーサーを実験的に取得する.
- 獲得された間隔器を含むバクテリアにおけるプラズミド喪失の観察.
- プラズミドと細菌のDNAに対するCRISPR1/CasシステムのDNA分裂活動のインビボ分析.
主要な成果:
- ストレプトコッカス・サーモフィルス (Streptococcus thermophilus) のCRISPR1/Casシステムは,自己複製性プラズミドからスペーサーを取得し,その結果,プラズミドが失われました.
- 抗生物質耐性遺伝子を標的にした得られたスペーサーは,プラズミドの吸収と拡散に対して免疫を与えました.
- イン・ビボ試験では,プラズミドとバクテリオファージの二重鎖DNAのCRISPR1/Casシステムによる特定の割れが,プロト・スペーサーの部位で確認された.
結論:
- CRISPR/Casの免疫システムは適応性があり,ウイルスのゲノムだけでなく,自己複製性プラズミッドを標的にすることができます.
- この自然選択メカニズムは,抗生物質耐性遺伝子の吸収と拡散を防ぐ.
- CRISPR/Casシステムの効率的なDNA分裂能力は,より安全な微生物株を開発する可能性を秘めています.
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