Journal de la nanomédecine et de la nanotechnologie

Abstrait

The Conjugative Transfer of the Multiresistance Gene Between Bacteria is Significantly Promoted by Nano-Alumina

Zhigang Qiu, Dong Yang, Min Jin, Liangping Hu, Zhaoli Chen, Zhiqiang Shen, Jingfeng Wang, Xinwei Wang, Bin Zhang, Sha Liu, Yunmei Yu and Jun-Wen Li

Recently, the potential risks of nanomaterials and the spread of antibiotic resistance have become two important environmental concerns. The conjugative transfer of antibiotic resistance genes between bacteria is the most important pathway for the acquisition of antibiotic resistance by bacteria. Both environmental and genetic factors influence the conjugative transfer of antibiotic resistance genes in bacterial populations. The extent to which nanomaterials are able to bring about an increase in antibiotic resistance by regulating the conjugative transfer of antibiotic resistance genes in bacteria is still unknown. In this paper, an Orthogonal Design L64 (421) was used in duplicate to evaluate the effects of bacterial concentration, nano-alumina concentration, mating time, mating temperature and the interactions of those factors on the conjugation transfer in LB broth. The mechanisms by which nano-alumina promote the horizontal transfer of antibiotic multiresistance features were explored by morphological, biochemical, and molecular biological methods. We have shown that nano-alumina promotes the horizontal conjugative transfer multiresistance genes mediated by RP4 up to 250-fold in LB broth and 100-fold in PBS. And it would appear that the effect of promoting conjugative transfer of nano-alumina exceeds the effects of mating temperature and mating time. We also explored the mechanisms behind this phenomenon and demonstrated that nano-alumina is able to induce oxidative stress, cause the damage of bacterial cell membranes, enhance the transcriptional activity of conjugative genes and depress the global regulatory factor genes expression. The findings in this study support the notion that nano-alumina in the environment could result in ecological hazards. More important, an enhanced rate of plasmid transfer among micro-organisms may have an enormous impact on human health and environmental safety.