101. Antibiotics Promote Escherichia coli-Pseudomonas aeruginosaConjugation through Inhibiting Quorum Sensing
- Author
-
Lu, Yang, Zeng, Jianming, Wang, Linjing, Lan, Kai, E, Shunmei, Wang, Lina, Xiao, Qian, Luo, Qiang, Huang, Xianzhang, Huang, Bin, and Chen, Cha
- Abstract
ABSTRACTThe effect of antibiotics on horizontal gene transfer (HGT) is controversial, and the underlying mechanism remains poorly understood. Here, using Escherichia coliSM10λπ as the donor strain, which carries a chromosomally integrated RP4 plasmid, we investigated the effect of antibiotics on conjugational transfer of a mobilizable gentamicin (Gm) resistance plasmid. The results showed that an exposure to gentamicin that restricted the survival of recipient cells significantly enhanced SM10λπ-Pseudomonas aeruginosaPAO1 conjugation, which was attenuated by a deficiency of lasI-rhlI, genes associated with the generation of the quorum sensing signals N-acyl homoserine lactones (AHLs) in PAO1, or the deletion of the AHL receptor SdiA in SM10λπ. Subsequent mechanistic investigations revealed that a treatment with Gm repressed the mRNA expression of lasIand rhlIin PAO1 and upregulated traIexpression in SM10λπ. Moreover, PAO1 treated with other quorum sensing (QS)-inhibiting antibiotics such as azithromycin or chloramphenicol also showed a conjugation-promoting ability. On the other hand, when using non-AHL-producing E. colistrain EC600 as the recipient cells, the promoting effect of Gm on conjugation could not be observed. These data suggest that AHL-SdiA contributes to the effectiveness of antibiotics on plasmid conjugation. Collectively, our findings highlight the HGT-promoting effect of antibiotics and suggest quorum sensing as a promising target for controlling antibiotic resistance dissemination. These findings have implications for assessing the risks of antibiotic use and developing advisable antibiotic treatment protocols.
- Published
- 2017
- Full Text
- View/download PDF