Engemann, Christina A. and Adams, Laura and Knapp, Charles W. and Graham, David W. (2006) Disappearance of oxytetracycline resistance genes in aquatic systems. FEMS Microbiology Letters, 263 (2). pp. 176-182.Full text not available in this repository. (Request a copy from the Strathclyde author)
The disappearance of selected tetracycline resistance genes was investigated in different simulated receiving waters to determine conditions that maximize resistance gene loss after release. Wastewater from an operating cattle feedlot lagoon was provided to four pairs of duplicate 3-L flasks, and tet(O), tet(W), tet(M), tet(Q), and 16S rRNA gene levels were monitored over 29 days using realtime PCR. Treatments included simulated sunlight with 0, 25, and 250 mu g L-1 nominal oxytetracycline (OTC) levels, respectively, and 'dark' conditions. Gene disappearance rates were always highest when light was present, regardless of OTC level. First-order loss coefficients (k(d)) for the sum of resistance genes were 0.84, 0.75, and 0.81 day(-1) for 0.0, 25, and 250 mu g L-1 OTC treatments over the first 7 days after release, respectively, whereas kd was 0.49 day l under dark conditions, which is significantly lower (P < 0.10). k(d) varied fourfold among the four individual genes, although disappearance patterns were similar among genes. Results suggest that light exposure should be maximized in receiving waters in order to maximize resistance gene loss rate after release.
|Keywords:||antibiotic resistance, oxytetracycline, real-time PCR, gene, disappearance kinetics, aquatic systems, Microbiology, Genetics, Molecular Biology, Microbiology|
|Subjects:||Science > Microbiology|
|Department:||Faculty of Engineering > Civil and Environmental Engineering|
|Depositing user:||Dr Charles W Knapp|
|Date Deposited:||04 Mar 2010 15:10|
|Last modified:||04 Nov 2016 03:25|