title: Conjugation is necessary for a bacterial plasmid to survive under protozoan predation.
abstract: Horizontal gene transfer by conjugative plasmids plays a critical role in the evolution of antibiotic resistance. Interactions between bacteria and other organisms can affect the persistence and spread of conjugative plasmids. Here we show that protozoan predation increased the persistence and spread of the antibiotic resistance plasmid RP4 in populations of the opportunist bacterial pathogen Serratia marcescens. A conjugation-defective mutant plasmid was unable to survive under predation, suggesting that conjugative transfer is required for plasmid persistence under the realistic condition of predation. These results indicate that multi-trophic interactions can affect the maintenance of conjugative plasmids with implications for bacterial evolution and the spread of antibiotic resistance genes.
authors: Department of Food and Environmental Sciences/Microbiology and Biotechnology, University of Helsinki, PO Box 65, Helsinki 00014, Finland.
authors: Johannes
authors: J
authors: Cairns
authors: Department of Biological and Environmental Science/Centre of Excellence in Biological Interactions, University of Jyväskylä, PO Box 35, Jyväskylä 40014, Finland.
authors: Matti
authors: M
authors: Jalasvuori
authors: Department of Biological and Environmental Science/Centre of Excellence in Biological Interactions, University of Jyväskylä, PO Box 35, Jyväskylä 40014, Finland.
authors: Ville
authors: V
authors: Ojala
authors: Department of Biology, University of York, York YO10 5DD, UK.
authors: Michael
authors: M
authors: Brockhurst
authors: Department of Food and Environmental Sciences/Microbiology and Biotechnology, University of Helsinki, PO Box 65, Helsinki 00014, Finland teppo.hiltunen@helsinki.fi.
authors: Teppo
authors: 0000-0001-7206-2399
authors: T
authors: Hiltunen
mesh_terms: D003227:Conjugation, Genetic; D020387:Food Chain; D010957:Plasmids / Q000235:genetics*; D012706:Serratia marcescens / Q000235:genetics*; D016808:Tetrahymena thermophila / Q000502:physiology*
keywords: RP4 plasmid; Serratia marcescens; Tetrahymena thermophila; conjugation; evolution of antibiotic resistance; protozoan predation