関連する実験動画
Updated: May 12, 2026
03:57
Microtiter Dish Biofilm Formation Assay
Published on: January 31, 2011
Pseudomonas aeruginosaのバイオフィルム,抗生物質耐性に対する遺伝的根拠
Thien-Fah Mah1, Betsey Pitts, Brett Pellock
1Department of Microbiology and Immunology, Dartmouth Medical School, Hanover, New Hampshire 03755, USA.
Nature
|November 25, 2003
まとめ
Pseudomonas aeruginosaのバイオフィルムは,ペリプラズマ性グルカンにより高い抗生物質耐性を発達させる. 特定の遺伝子ndvBは,バイオフィルムにおけるこの耐性メカニズムに不可欠です.
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.
- バイオケミストリー バイオケミストリー
背景:
- バイオフィルムは,抗生物質に対する有意な耐性を含むユニークな性質を持つ微生物のコミュニティです.
- Pseudomonas aeruginosaは,回復力のあるバイオフィルムを形成することが知られている機会的病原体です.
研究 の 目的:
- Pseudomonas aeruginosaのバイオフィルムにおける高レベルの抗生物質耐性に貢献する遺伝的要因を特定する.
- バイオフィルムが抗生物質耐性を引き起こすメカニズムを解明する.
主な方法:
- バイオフィルム抗生物質耐性が低下した変異体を特定するための遺伝子スクリーニング.
- バイオフィルム構造と抗生物質感受性の特徴.
- 周辺プラズマ成分と抗生物質との相互作用の生化学分析.
主要な成果:
- ndvB遺伝子を欠いた変異体がバイオフィルムを形成したが,複数の抗生物質クラスに対する耐性が著しく低下した.
- ndvB遺伝子は,ペリプラズマ性グルカンの合成に不可欠である.
- 周辺プラズマのグルカンは,トブラマイシンと物理的に相互作用し,周辺プラズマに閉じ込めることが判明しました.
結論:
- ndvBロカス経由で合成されるペリプラズマ性グルカンは,P. aeruginosaのバイオフィルムにおける高レベルの抗生物質耐性の重要な決定因子である.
- この耐性メカニズムは,バイオフィルムマトリックスによる拡散制限のみではなく,周辺プラズマ内の抗生物質の物理的封じ込めを含みます.
- バイオフィルム内のバクテリアは,プランクトンの耐性とは異なり,抗生物質に抵抗する特定の分子機構を採用しています.
関連する概念動画
00:57Antibiotic Selection
Overview
01:29Biofilms
Biofilms are complex communities of microorganisms encased in a self-produced extracellular polysaccharide matrix attached to surfaces. These microbial consortia can include single or multiple species, providing enhanced survival benefits by forming organized, multilayered structures.The formation of biofilms occurs through four key stages: attachment, colonization, development, and dispersal.During attachment, free-swimming planktonic cells adhere to a surface, often facilitated by...
01:28Gene Regulation in Microbial Communities: Quorum Sensing
Quorum sensing is a mechanism of bacterial communication that enables coordinated gene expression in response to changes in population density. This facilitates collective behaviors that enhance survival, resource acquisition, and ecological adaptation. This process relies on small signaling molecules called autoinducers that accumulate as bacterial populations grow. When a critical threshold concentration of autoinducers is reached, bacterial cells collectively modify gene expression,...
01:30Development of Antibiotic Resistance
Antibiotic resistance is a major public health concern that arises when bacteria evolve mechanisms to withstand the effects of antibiotic treatments. This resistance can be intrinsic, acquired through genetic mutations, or transferred between bacteria via horizontal gene transfer. The development of antibiotic resistance poses significant challenges in treating bacterial infections and necessitates ongoing research to develop new therapeutic strategies.Intrinsic resistance occurs when bacterial...
01:25Mechanism of Antibiotic Resistance in MRSA
Antibiotic resistance in bacteria arises when microorganisms evolve the ability to withstand drugs designed to kill them or inhibit their growth, rendering once-effective treatments useless. This phenomenon, driven by genetic change and selection under antibiotic exposure, poses a profound threat to modern medicine. Mechanisms include drug-inactivating enzymes (e.g., β-lactamases), efflux pumps that eject antibiotics, mutations altering antibiotic targets, decreased drug uptake, and acquisition...
01:25Clinical Significance of Antibiotic Resistance
Methicillin-resistant Staphylococcus aureus (MRSA) presents a critical public health threat, arising from its capacity to resist β-lactam antibiotics due to acquisition of the mecA gene within the staphylococcal cassette chromosome mec (SCCmec). This gene encodes penicillin-binding protein 2a (PBP2a), which impairs binding efficacy of methicillin and other β-lactams. MRSA has evolved into distinct clonal lineages impacting humans and animals alike, reinforcing its significance within the One...