title: Antibiotics as a selective driver for conjugation dynamics.
abstract: It is generally assumed that antibiotics can promote horizontal gene transfer. However, because of a variety of confounding factors that complicate the interpretation of previous studies, the mechanisms by which antibiotics modulate horizontal gene transfer remain poorly understood. In particular, it is unclear whether antibiotics directly regulate the efficiency of horizontal gene transfer, serve as a selection force to modulate population dynamics after such gene transfer has occurred, or both. Here, we address this question by quantifying conjugation dynamics in the presence and absence of antibiotic-mediated selection. Surprisingly, we find that sublethal concentrations of antibiotics from the most widely used classes do not significantly increase the conjugation efficiency. Instead, our modelling and experimental results demonstrate that conjugation dynamics are dictated by antibiotic-mediated selection, which can both promote and suppress conjugation dynamics. Our findings suggest that the contribution of antibiotics to the promotion of horizontal gene transfer may have been overestimated. These findings have implications for designing effective antibiotic treatment protocols and for assessing the risks of antibiotic use.
authors: Department of Biomedical Engineering, Duke University, Durham, North Carolina, USA.
authors: Allison J
authors: AJ
authors: Lopatkin
authors: Department of Biomedical Engineering, Duke University, Durham, North Carolina, USA.
authors: Shuqiang
authors: S
authors: Huang
authors: Department of Biological Sciences, Halmos College of Natural Sciences and Oceanography, Nova Southeastern University, Fort Lauderdale, Florida, USA.
authors: Robert P
authors: RP
authors: Smith
authors: Department of Biomedical Engineering, Duke University, Durham, North Carolina, USA.
authors: Jaydeep K
authors: JK
authors: Srimani
authors: Department of Biomedical Engineering, Duke University, Durham, North Carolina, USA.
authors: Tatyana A
authors: TA
authors: Sysoeva
authors: Department of Biology, University of Maryland, College Park, Maryland 20742, USA.
authors: Sharon
authors: S
authors: Bewick
authors: Research and Exploratory Development Department, Applied Physics Laboratory, Johns Hopkins University Laurel, Maryland, USA.
authors: David K
authors: DK
authors: Karig
authors: Department of Biomedical Engineering, Duke University, Durham, North Carolina, USA.|Center for Genomic and Computational Biology, Duke University, Durham, North Carolina, USA.
authors: Lingchong
authors: L
authors: You
mesh_terms: D000900:Anti-Bacterial Agents / Q000009:adverse effects / Q000494:pharmacology* / Q000627:therapeutic use; D003227:Conjugation, Genetic / Q000187:drug effects*; D024881:Drug Resistance, Bacterial / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics*; D006801:Humans; D008826:Microbial Sensitivity Tests; D046210:Microfluidic Analytical Techniques; D008954:Models, Biological; D056004:Molecular Dynamics Simulation; D010957:Plasmids / Q000187:drug effects; D012641:Selection, Genetic
chemical_list: D000900:Anti-Bacterial Agents