Contents lists available at ScienceDirect Journal of Hazardous Materials journal homepage: www.elsevier.com/locate/jhazmat Selection and propagation of IncP conjugative plasmids following long-term anthropogenic metal pollution in river sediments Valentine Cyriaque a,b, ⁎ ,1 , Samuel Jacquiod b,c,1 , Leise Riber d , Waleed Abu Al-soud b,e , David C. Gillan a , Søren J. Sørensen b,2 , Ruddy Wattiez a,2 a Proteomics and Microbiology Laboratory, Research Institute for Biosciences, UMONS, 20 place du parc, Mons, Belgium b Section of Microbiology, Department of Biology, University of Copenhagen, Universitetsparken 15, 2100 Copenhagen Ø, 1, Bygning, 1-1-215, Denmark c Agroécologie, UMR 1347, INRA Centre Dijon, Dijon, France d Section of Functional Genomics, Department of Biology, University of Copenhagen, Ole Maaløesvej 5, 2200 Copenhagen N, Denmark e Department of Clinical Laboratory Sciences, Faculty of Applied Medical Sciences, Jouf University, Qurayyat, Saudi Arabia GRAPHICAL ABSTRACT ARTICLE INFO Editor: Deyi Hou Keywords: Horizontal gene transfer Conjugative plasmid Metal pollution River sediment FACS Sequencing ABSTRACT For a century, the MetalEurop foundry released metals into the river “La Deûle”. Previous work revealed higher microbial diversity in metal impacted sediments, and horizontal gene transfer mediated by conjugative plasmids was suggested to drive the community adaptation to metals. We used an integrative state-of-the-art molecular approach coupling quantitative PCR, conjugation assays, flow cytometry, fluorescence activated cell sorting and 16S rRNA gene amplicon sequencing to investigate the presence of conjugative plasmids and their propagation patterns in sediment microbiomes. We highlighted the existence of a native broad-host range IncP conjugative plasmid population in polluted sediments, confirming their ecological importance for microbial adaptation. However, despite incompatibilities and decreased transfer frequencies with our own alien IncP plasmid, we evidenced that a wide diversity of bacterial members was still prone to uptake the plasmid, indicating that sediment microbial communities are still inclined to receive conjugative plasmids from the same group. We observed that metal pollution favoured exogenous plasmid transfer to specific metal-selected bacteria, which are https://doi.org/10.1016/j.jhazmat.2019.121173 Received 23 May 2019; Received in revised form 14 August 2019; Accepted 5 September 2019 Abbreviations: FACS, fluorescence activated cell sorting; FRG, Functional Response Group; GFP, green fluorescent protein; HGT, horizontal gene transfer; MGE, mobile genetic element; SMCs, sediment microbial communities; OTU, operational taxonomic unit; qPCR, quantitative polymerase chain reaction; WWTP, waste- water treatment plant ⁎ Corresponding author at: Proteomics and Microbiology Laboratory, Research Institute for Biosciences, UMONS, 20 place du parc, Mons, Belgium. E-mail address: valentine.cyriaque@umons.ac.be (V. Cyriaque). 1 These authors have contributed equally as shared-first authors. 2 These authors have contributed equally as shared-last authors. Journal of Hazardous Materials 382 (2020) 121173 Available online 06 September 2019 0304-3894/ © 2019 Elsevier B.V. All rights reserved. T