摘要

       纳米材料污染和抗生素抗性基因 (ARG) 的传播是全球公共卫生和环境问题。纳米材料是否有助于将死细菌释放的 ARGs 转移到活细菌中，从而导致 ARGs 的传播，目前尚不清楚。在这里，我们证明了纳米 Al2O3 可以显着促进质粒介导的 ARGs 转化为革兰氏阴性大肠杆菌菌株和革兰氏阳性金黄色葡萄球菌；然而，块状 Al2O3 没有这种效果。在合适的条件下，当细菌用纳米Al2O3处理时，从100 ng基于pBR322的质粒获得7.4 × 106个大肠杆菌转化体和2.9 × 105个金黄色葡萄球菌转化体。纳米颗粒浓度、质粒浓度、细菌浓度、纳米材料与细菌细胞之间的相互作用时间和涡旋时间影响转化效率。我们还探讨了这种现象背后的机制。使用荧光原位杂交和扫描电镜，我们发现纳米Al2O3 破坏细胞膜产生孔，质粒可以通过这些孔进入细菌细胞。活性氧 (ROS) 测定、全基因组表达微阵列分析和定量实时聚合酶链反应的结果表明细胞内 ROS 损坏了细胞膜，并且 SOS 反应促进了质粒转化。我们的研究结果表明，纳米材料帮助敏感细菌获得抗生素抗性会导致环境和健康风险。

       Nanomaterial contamination and the spread of antibiotic resistance genes (ARG) are global public health and environmental issues. Whether nanomaterials can help transfer ARGs released by dead bacteria to live bacteria, thereby leading to the spread of ARGs, is currently unclear. Here, we demonstrated that nano Al2O3 can significantly promote plasmid-mediated ARGs transformation into Gram-negative E. coli strains and Gram-positive Staphylococcus aureus; however, massive Al2O3 does not have this effect. Under suitable conditions, when the bacteria were treated with nano-Al2O3, 7.4 × 106 transformants of E. coli and 2.9 × 105 transformants of Staphylococcus aureus were obtained from 100 ng of pBR322-based plasmid. Nanoparticle concentration, plasmid concentration, bacterial concentration, interaction time between nanomaterials and bacterial cells, and vortex time affect transformation efficiency. We also explored the mechanism behind this phenomenon. Using fluorescence in situ hybridization and scanning electron microscopy, we found that nano-Al2O3 destroys the cell membrane to create pores through which plasmids can enter bacterial cells. The results of reactive oxygen species (ROS) measurement, genome-wide expression microarray analysis, and quantitative real-time polymerase chain reaction showed that intracellular ROS damaged the cell membrane, and the SOS reaction promoted plasmid transformation. Our research results show that nanomaterials help sensitive bacteria acquire antibiotic resistance, which can lead to environmental and health risks.

https://www.tandfonline.com/doi/abs/10.3109/17435390.2016.1161856