title: Daphnia as a refuge for an antibiotic resistance gene in an experimental freshwater community.
abstract: Mechanisms that enable the maintenance of antibiotic resistance genes in the environment are still greatly unknown. Here we show that the tetracycline resistance gene tet(A) is largely removed from the pelagic aquatic bacterial community through filter feeding by Daphnia obtusa while it becomes detectable within the microbiome of the daphniids themselves, where it was not present prior to the experiment. We moreover show that a multitude of Daphnia-associated bacterial taxa are potential carriers of tet(A) and postulated that the biofilm-like structures, where bacteria grow in, may enable horizontal transfer of such genes. This experiment highlights the need to take ecological interactions and a broad range of niches into consideration when studying and discussing the fate of antibiotic resistance genes in nature.
authors.affiliation: Microbial Ecology Group, National Research Council - Institute of Ecosystem Study (CNR-ISE), Largo Tonolli, 50, 28922 Verbania, Italy.
authors.forename: Ester M
authors.initials: EM
authors.lastname: Eckert
authors.affiliation: Microbial Ecology Group, National Research Council - Institute of Ecosystem Study (CNR-ISE), Largo Tonolli, 50, 28922 Verbania, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Di Cesare
authors.affiliation: Microbial Ecology Group, National Research Council - Institute of Ecosystem Study (CNR-ISE), Largo Tonolli, 50, 28922 Verbania, Italy; Institut für Botanik, University of Innsbruck, Sternwartestraße 15, 6020 Innsbruck, Austria.
authors.forename: Birgit
authors.initials: B
authors.lastname: Stenzel
authors.affiliation: Microbial Ecology Group, National Research Council - Institute of Ecosystem Study (CNR-ISE), Largo Tonolli, 50, 28922 Verbania, Italy.
authors.forename: Diego
authors.initials: D
authors.lastname: Fontaneto
authors.affiliation: Microbial Ecology Group, National Research Council - Institute of Ecosystem Study (CNR-ISE), Largo Tonolli, 50, 28922 Verbania, Italy. Electronic address: g.corno@ise.cnr.it.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Corno
mesh_terms: D000818:Animals; D017920:Antiporters / Q000032:analysis*; D001419:Bacteria / Q000235:genetics*; D001426:Bacterial Proteins / Q000032:analysis*; D003621:Daphnia / Q000382:microbiology* / Q000502:physiology; D005247:Feeding Behavior; D007558:Italy; D060106:Lakes / Q000382:microbiology; D064307:Microbiota; D013752:Tetracycline / Q000494:pharmacology; D013753:Tetracycline Resistance
chemical_list: D017920:Antiporters; D001426:Bacterial Proteins; C079051:tetA protein, Bacteria; D013752:Tetracycline
keywords: ARGs; Antibiotic resistance; Bacterial community; Daphnia; Freshwaters; Tetracycline