微塑料对细菌耐药性的大小和表面电荷依赖的抑制作用以及它们与类抗生素的相互作用作用
Hongyan Shen1, Mingru Yang1, Kangnian Yin1
1School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, China.
The Science of the total environment
|August 26, 2023
概括
微塑料 (MP) 和抗生素可以增加细菌的耐药性. 这项研究发现,微塑料,特别是较小的,带有正电荷的微塑料,以及它们与诺弗洛素 (NOR) 的混合物,在细菌突变和等离子体转移频率上诱导了hormetic剂量反应.
科学领域:
- 环境科学 环境科学
- 微生物学 微生物学
- 毒理学 毒理学 毒理学
背景情况:
- 微塑料 (MP) 是普遍存在的环境污染物. 国会议员可以与细菌相互作用,可能影响抗生素耐药性. 同时暴露于MPs和抗生素可能会对细菌生存和耐药性构成联合风险.
- 了解MPs和MP-抗生素混合物对细菌耐药性的剂量反应关系对于环境风险评估至关重要.
研究的目的:
- 调查不同类型的微塑料 (MP) 和MP-抗生素混合物对细菌内源性和外源性耐药性的剂量反应.
- 阐明MP大小和表面电荷对细菌突变频率 (MF) 和结合转移频率 (CTF) 的影响.
- 探索MP和抗生素对细菌耐药性和潜在机制的相互作用作用.
主要方法:
- 在大肠杆菌 (大肠杆菌) 上测试了六种类型的聚乙烯MPs (0.1和5微米;非功能化,氨基功能化,炭基功能化) 和norfloxacin (NOR).
- 使用剂量反应实验评估了MPs和MP-NOR混合物对大肠杆菌生长,MF和CTF的影响.
- 分析了MP及其混合物的尺寸和表面电荷依赖的影响.
- 研究的机制包括反应性氧物种 (ROS) 生产和细胞膜透性.
主要成果:
- 所有测试的MP都抑制了大肠杆菌的生长,但在MF和CTF上诱导了hormetic剂量反应,表明在某些度下细菌耐药性增加.
- 激素效应取决于尺寸和表面电荷,0.1μm的氨基功能化PS显示了MF和CTF的最大刺激率.
- MP-NOR混合物也对MF和CTF表现出抑制作用,相互作用效应表明与单一污染物相比,耐药性风险更大.
- 增加的ROS和改变的细胞膜透性被确定为有助于这些抑制作用的机制.
结论:
- 微塑料,特别是较小和正电荷的微塑料,可以刺激细菌突变和等离子体转移频率,从而导致抗生素耐药性.
- 微塑料和抗生素的组合可能会加剧细菌耐药性的风险.
- 涉及氧化应激和改变膜透性的机制参与了微塑料诱导的细菌耐药性.
- 这项研究为评估微塑料对细菌耐药性的环境风险提供了关键的见解.
相关概念视频
Gene Regulation in Microbial Communities: Quorum Sensing
39
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,...
39
Antimicrobial Effectiveness
44
The effectiveness of antimicrobial agents depends on various factors influencing their ability to eliminate microbial populations. Larger microbial populations require more time for complete eradication, emphasizing the importance of population size analysis when evaluating antimicrobial efficacy.Microbial resistance to antimicrobial agents varies significantly. Highly resilient microorganisms include endospores, gram-negative bacteria, and non-enveloped viruses, while prions are exceptionally...
44
Development of Antibiotic Resistance
38
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...
38
Biofilms
55
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...
55


