title: Metagenomic profiling of historic Colorado Front Range flood impact on distribution of riverine antibiotic resistance genes.
abstract: Record-breaking floods in September 2013 caused massive damage to homes and infrastructure across the Colorado Front Range and heavily impacted the Cache La Poudre River watershed. Given the unique nature of this watershed as a test-bed for tracking environmental pathways of antibiotic resistance gene (ARG) dissemination, we sought to determine the impact of extreme flooding on ARG reservoirs in river water and sediment. We utilized high-throughput DNA sequencing to obtain metagenomic profiles of ARGs before and after flooding, and investigated 23 antibiotics and 14 metals as putative selective agents during post-flood recovery. With 277 ARG subtypes identified across samples, total bulk water ARGs decreased following the flood but recovered to near pre-flood abundances by ten months post-flood at both a pristine site and at a site historically heavily influenced by wastewater treatment plants and animal feeding operations. Network analysis of de novo assembled sequencing reads into 52,556 scaffolds identified ARGs likely located on mobile genetic elements, with up to 11 ARGs per plasmid-associated scaffold. Bulk water bacterial phylogeny correlated with ARG profiles while sediment phylogeny varied along the river's anthropogenic gradient. This rare flood afforded the opportunity to gain deeper insight into factors influencing the spread of ARGs in watersheds.
authors.affiliation: Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, VA 24061, USA.
authors.forename: Emily
authors.initials: E
authors.lastname: Garner
authors.affiliation: Department of Chemistry, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA.
authors.forename: Joshua S
authors.initials: JS
authors.lastname: Wallace
authors.affiliation: Department of Computer Science, Virginia Tech, Blacksburg, VA 24061, USA.
authors.forename: Gustavo Arango
authors.initials: GA
authors.lastname: Argoty
authors.affiliation: Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, VA 24061, USA.
authors.forename: Caitlin
authors.initials: C
authors.lastname: Wilkinson
authors.affiliation: Department of Civil and Environmental Engineering, Rutgers University, Piscataway, NJ 08854, USA.
authors.forename: Nicole
authors.initials: N
authors.lastname: Fahrenfeld
authors.affiliation: Department of Computer Science, Virginia Tech, Blacksburg, VA 24061, USA.
authors.forename: Lenwood S
authors.initials: LS
authors.lastname: Heath
authors.affiliation: Department of Computer Science, Virginia Tech, Blacksburg, VA 24061, USA.
authors.forename: Liqing
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Civil and Environmental Engineering, Colorado State University, Fort Collins, CO, 80523, USA.
authors.forename: Mazdak
authors.initials: M
authors.lastname: Arabi
authors.affiliation: Department of Chemistry, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA.
authors.forename: Diana S
authors.initials: DS
authors.lastname: Aga
authors.affiliation: Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, VA 24061, USA.
authors.forename: Amy
authors.initials: A
authors.lastname: Pruden
mesh_terms: D001419:Bacteria / Q000187:drug effects / Q000235:genetics* / Q000472:pathogenicity; D003120:Colorado; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D055868:Floods; D006801:Humans; D054892:Metagenome / Q000235:genetics*; D056186:Metagenomics; D010802:Phylogeny; D045483:Rivers / Q000382:microbiology; D014871:Water Microbiology