逆转范式:nTiO2的依赖氧的切换从促进到抑制ARG结合
Jie Yu1, Xin Wang1, Ya-Xin Hu1
1Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China.
Journal of hazardous materials
|November 16, 2025
概括
纳米二氧化 (nTiO2) 通过活性氧物种 (ROS) 在有氧条件下促进抗生素耐药性基因 (ARG) 转移,但通过物理障碍在无氧状态下抑制它. 这澄清了纳米材料对环境ARG传播的影响.
科学领域:
- 环境科学 环境科学
- 微生物学 微生物学
- 纳米技术 纳米技术
背景情况:
- 抗生素耐药性基因 (ARG) 通过环境传播,构成公共卫生风险.
- 已知纳米二氧化 (nTiO2) 影响ARG转移,但其在无氧环境中的影响尚不清楚.
研究的目的:
- 在有氧和无氧条件下研究nTiO2对等离子体介导的ARG结合的影响.
- 阐明 nTiO2 在不同氧气环境中对ARG转移的影响背后的机制.
主要方法:
- 细菌群体在受控的有氧和无氧条件下暴露于nTiO2.
- 使用结合试验 (属内和属内) 量化ARG转移速率.
- 评估活性氧物种 (ROS) 水平和利用ROS清除剂 (尿素) 和诱导剂 (H2O2) 的使用情况.
主要成果:
- 有氧条件:nTiO2显著促进了ARG转移,这是由ROS诱导的膜透性和通路下调驱动的.
- 无氧条件:nTiO2显著抑制了ARG转移,可能是由于物理吸附障碍.
- ROS操纵 (清理器/诱导器) 证实了ROS和物理效应在调节nTiO2影响中的独特作用.
结论:
- nTiO2对ARG结合具有双重作用:通过ROS促进有氧结合,通过物理障碍抑制无氧结合.
- 了解这些独特的机制对于评估纳米材料对抗生素耐药性的环境风险至关重要.
- 这项研究提供了关于ARG在纳米材料暴露下的环境传播的关键见解.
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