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Updated: Aug 28, 2026

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Testing the Role of Multicopy Plasmids in the Evolution of Antibiotic Resistance
Published on: May 2, 2018
移転可能なプラズミドからのキノロン耐性
L Martínez-Martínez1, A Pascual, G A Jacoby
1Department of Clinical Microbiology, School of Medicine, University of Seville, Spain.
Lancet (London, England)
|March 31, 1998
まとめ
Klebsiella pneumoniaeからの多抵抗性プラズミッドは,細菌間のキノロン抵抗性を転送することができます. このプラズミッドは,重要な抗菌剤に対する耐性の発達と拡散を加速します.
科学分野:
- 微生物学 微生物学とは
- 遺伝学 遺伝学とは
- 抗菌剤耐性菌は,抗菌剤耐性菌である.
背景:
- 細菌はターゲットの変化や薬物の蓄積の減少によってキノロン耐性を発達させる.
- プラズミド媒介のキノロン耐性については,臨床単離体ではまだ確認されていない.
- この研究では,多抵抗性プラズミドを介してキノロン抵抗性の移転性を調査しています.
研究 の 目的:
- 多抵抗性プラズミドがキノロン抵抗性を細菌株間で転送できるかどうかを判断する.
- キノロン耐性レベルに対するプラズミド移転の影響を評価する.
- プラズミド媒介キノロン抵抗性の強化における自発的な変異の役割を調査する.
主な方法:
- 結合は,耐性プラズミド (pMG252) を細菌株間で転送するために使用されました.
- アガロースゲル電泳は,様々な宿主におけるプラズミドを視覚化しました.
- シプロフロクサシンとナリジキス酸に対する耐性を引き起こす自発的な変異の頻度は,プラズミドを併用したEscherichia coli菌株および無プラズミドのEscherichia coli菌株で決定されました.
主要な成果:
- pMG252プラズミッドは,外膜ポリンが欠けているKlebsiella pneumoniae株のキノロン抵抗性を増加させた (シプロフロクサシンMICは32μg/mLまで).
- 低抵抗レベルは,正常なポリンを持つ株で観察されましたが,プラズミッドは,E. coli,他のエンテロバクテリア科,およびPseudomonas aeruginosaを含む広範な宿主範囲を示しました.
- キノロン耐性突然変異体は,プラズミドを含む大腸菌で100倍以上の頻度で発生し,より高い最小抑制濃度 (MIC) に達しました.
結論:
- 移転可能なキノロンおよびナリディキス酸に対する耐性は,広範囲の宿主プラズミドの臨床Klebsiella pneumoniae分離で確認されました.
- プラズミド媒介による耐性は野生型株では低かったが,自発的な変異によって耐性レベルは容易に上昇した.
- そのようなプラズミッドは,重要な抗菌薬に対する耐性の出現と拡散を大幅に加速することができます.
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