バクテリアの慈善活動は,全人口の耐性につながる
Henry H Lee1, Michael N Molla, Charles R Cantor
1Howard Hughes Medical Institute, Center for BioDynamics, Boston, Massachusetts 02115, USA.
Nature
|September 3, 2010
まとめ
高耐性細菌の変異種は,シグナル伝達分子であるインドルを生成することによって,脆弱な細胞を保護します. この"細菌的利他主義"は,親族の選択を通じて,抗生物質に対する集団の生存率を高めます.
科学分野:
- 微生物学 微生物学とは
- 進化生物学の進化生物学について
- 遺伝学 遺伝学とは
背景:
- バクテリアは,耐性メカニズムを通じて,抗生物質に適応する能力を発揮します.
- 抗生物質耐性を発達させる人口動態は十分に理解されていません.
- 個々の抵抗性アレルとストレス反応は知られているが,集団レベルでの戦略は明確ではない.
研究 の 目的:
- エシェリキア・コライ菌における抗生物質耐性の発達中の集団動態を調査する.
- 抵抗性の高い突然変異体が,抵抗性の低い細胞の生存に影響を与えるメカニズムを理解する.
- 集団レベルの抗生物質耐性におけるバクテリアシグナル伝達分子の役割を調査する.
主な方法:
- 抗生物質濃度の上昇に曝されたEscherichia coliの連続培養.
- 集団全体と比較した単離剤耐性の分析.
- 分子メカニズムを特定するための転写プロファイリング.
- 耐性突然変異体の全ゲノム配列決定. 耐性突然変異体の全ゲノム配列決定.
主要な成果:
- ほとんどのバクテリアの単離は,全集団よりも抵抗性が低い.
- 高耐性突然変異は,インドル生成を介して,より抵抗性の低い細胞の生存を向上させた.
- インドールは,薬物の流出ポンプと酸化ストレス防御を活性化させます.
- 抵抗性突然変異はインドル産生とは独立しており,利他主義に対するフィットネスコストを示唆している.
結論:
- 親族の選択に似た集団ベースの抵抗メカニズムが特定されました.
- 耐性突然変異体は,脆弱な細胞に,適性コストで保護を提供することができる.
- この利他的な行動は,抗生物質ストレス環境における細菌集団の全体的な生存率を高めます.
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