title: Performance and microbial community variations of anaerobic digesters under increasing tetracycline concentrations.
abstract: The impact of different concentrations of tetracycline on the performance of anaerobic treatment was evaluated. Results revealed that for all of the tested tetracycline concentrations, no major sustained impact on methane production was observed. Instead, a significant increase in propionic acid was observed in the reactor subjected to the highest concentration of tetracycline (20 mg/L). Microbial community analyses suggest that an alternative methanogenic pathway, specifically that of methanol-utilizing methanogens, may be important for ensuring the stability of methane production in the presence of high tetracycline concentrations. In addition, the accumulation of propionate was due to an increase in volatile fatty acids (VFA)-producing bacteria coupled with a reduction in propionate utilizers. An increase in the abundance of tetracycline resistance genes associated with ribosomal protection proteins was observed after 30 days of exposure to high concentrations of tetracycline, while other targeted resistance genes showed no significant changes. These findings suggest that anaerobic treatment processes can robustly treat wastewater with varying concentrations of antibiotics while also deriving value-added products and minimizing the dissemination of associated antibiotic resistance genes.
authors.affiliation: King Abdullah University of Science and Technology (KAUST), Water Desalination and Reuse Center (WDRC), Biological and Environmental Science & Engineering Division (BESE), Thuwal, 23955-6900, Saudi Arabia.
authors.forename: Yanghui
authors.initials: Y
authors.lastname: Xiong
authors.affiliation: King Abdullah University of Science and Technology (KAUST), Water Desalination and Reuse Center (WDRC), Biological and Environmental Science & Engineering Division (BESE), Thuwal, 23955-6900, Saudi Arabia.
authors.forename: Moustapha
authors.initials: M
authors.lastname: Harb
authors.affiliation: King Abdullah University of Science and Technology (KAUST), Water Desalination and Reuse Center (WDRC), Biological and Environmental Science & Engineering Division (BESE), Thuwal, 23955-6900, Saudi Arabia. peiying.hong@kaust.edu.sa.
authors.forename: Pei-Ying
authors.identifier: http://orcid.org/0000-0002-4474-6600
authors.initials: PY
authors.lastname: Hong
mesh_terms: D000693:Anaerobiosis; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D019149:Bioreactors / Q000382:microbiology; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D005232:Fatty Acids, Volatile / Q000378:metabolism; D008697:Methane / Q000378:metabolism; D059013:Microbial Consortia / Q000187:drug effects* / Q000502:physiology; D011422:Propionates / Q000378:metabolism; D013752:Tetracycline / Q000494:pharmacology*; D014865:Waste Disposal, Fluid; D062065:Wastewater / Q000382:microbiology
chemical_list: D000900:Anti-Bacterial Agents; D005232:Fatty Acids, Volatile; D008697:Methane; D011422:Propionates; D013752:Tetracycline; D062065:Wastewater; C029658:propionic acid
keywords: Anaerobic digestion; Methanogenic pathway; Propionic acid; Tetracycline; Tetracycline resistance genes