窒素酸化物誘導性乳酸脱水素酵素は,Staphylococcus aureusが先天性免疫に抵抗することを可能にします
Anthony R Richardson1, Stephen J Libby, Ferric C Fang
1Department of Laboratory Medicine, University of Washington, Seattle, WA 98195, USA.
Science (New York, N.Y.)
|March 22, 2008
まとめ
Staphylococcus aureusは,有害な酸化窒素 (NO) を生き残るのに役立つ乳酸を生産することによって,免疫防御に適応します. この代謝適応は,病原体にとって極めて重要です.
科学分野:
- 微生物学 微生物学とは
- 感染症 感染症は感染症です.
- バクテリア病原菌の発生
背景:
- Staphylococcus aureusは,世界中で数十億人に影響を与える主要なヒト病原体です.
- S. aureusは,抗菌性窒素酸化物 (NO) を含む宿主の先天的免疫を回避する.
- バクテリアの耐性メカニズムを理解することは,感染症と闘うための鍵です.
研究 の 目的:
- S. aureusの窒素化ストレスへの代謝適応を調査する.
- S. aureusが窒素酸化物曝露に耐えられるメカニズムを特定する.
- S. aureusの毒性およびNO耐性における特定の酵素の役割を決定する.
主な方法:
- ニトロゼーション性ストレス下におけるS. aureusにおける遺伝子発現の分析.
- 酵素活性 (L-乳酸脱水酸化酵素,フラボヘモグロビン) を測定するための生化学分析.
- 特定された経路の役割を評価するために,関連するモデルでのウイルス性研究.
主要な成果:
- S. aureusは,NO.への反応としてL-乳酸脱水素酶 (ldh1) の発現を誘導する.
- ldhlによるL-乳酸塩生成は,ニトロゼーション性ストレス中にレドックスホメオスタシスを維持する.
- NO誘導性乳酸脱水素酶活性とNO抵抗性は,関連種と比較してS. aureusに特異的です.
結論:
- L-乳酸塩の生産による代謝適応は,S. aureusの毒性にとって不可欠である.
- NO誘導性L-乳酸脱水素酵素の発現は,S. aureusにとって重要な生存メカニズムである.
- この経路は,S. aureusを共生性スタフィロコーシと区別し,潜在的な治療標的を強調しています.
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