title: Occurrence and prevalence of antibiotic resistance in landfill leachate.
abstract: Antibiotic resistance (AR) is extensively present in various environments, posing emerging threat to public and environmental health. Landfill receives unused and unwanted antibiotics through household waste and AR within waste (e.g., activated sludge and illegal clinical waste) and is supposed to serve as an important AR reservoir. In this study, we used culture-dependent methods and quantitative molecular techniques to detect and quantify antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) in 12 landfill leachate samples from six geographic different landfills, China. Five tested ARGs (tetO, tetW, bla(TEM), sulI, and sulII) and seven kinds of antibiotic-resistant heterotrophic ARB were extensively detected in all samples, demonstrating their occurrence in landfill. The detected high ratio (10(-2) to 10(-5)) of ARGs to 16S ribosomal RNA (rRNA) gene copies implied that ARGs are prevalent in landfill. Correlation analysis showed that ARGs (tetO, tetW, sulI, and sulII) significantly correlated to ambient bacterial 16S rRNA gene copies, suggesting that the abundance of bacteria in landfill leachate may play an important role in the horizontal spread of ARGs.
authors.affiliation: Research Center of Environmental Microbiology and Ecology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 401122, China.
authors.forename: Yangqing
authors.initials: Y
authors.lastname: Wang
authors.forename: Wei
authors.initials: W
authors.lastname: Tang
authors.forename: Jing
authors.initials: J
authors.lastname: Qiao
authors.forename: Liyan
authors.initials: L
authors.lastname: Song
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis*; D001419:Bacteria / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics; D002352:Carrier Proteins / Q000235:genetics; D002681:China; D004352:Drug Resistance, Microbial / Q000235:genetics*; D004783:Environmental Microbiology; D029968:Escherichia coli Proteins / Q000235:genetics; D005843:Geography; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D001618:beta-Lactamases / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; D012336:RNA, Ribosomal, 16S; C091882:Sul1 protein, E coli; C083139:Tet O resistance protein, Bacteria; D014874:Water Pollutants, Chemical; D001618:beta-Lactamases