College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China.
College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China; Research Center of Recycle Agricultural Engineering and Technology of Shaanxi Province, Northwest A&F University, Yangling, Shaanxi 712100, China.
Chemosphere. 2018 Apr;197:643-650. doi: 10.1016/j.chemosphere.2018.01.033. Epub 2018 Feb 3.
The presence of high concentrations of residual antibiotics and antibiotic resistance genes (ARGs) in soil may pose potential health and environmental risks. This study investigated the prevalence of plasmid-mediated quinolone resistance (PMQR) genes, copper resistance genes (CRGs), and the bacterial communities in a soil-ryegrass pot system co-polluted with copper and ciprofloxacin (CIP; 0, 20, or 80 mg kg dry soil). Compared with the samples on day 0, the total relative abundances of the PMQR genes and mobile genetic elements (MGEs) were reduced significantly by 80-89% in the ryegrass and soil by the cutting stage (after 75 days). The abundances of PMQR genes and MGEs were reduced by 63-81% in soil treated with 20 mg kg CIP compared with the other treatments, but the abundances of CRGs increased by 18-42%. The presence of 80 mg kg CIP affected the microbial community structure in the soil by increasing the abundances of Acidobacteria and Thaumarchaeota, but decreasing those of Firmicutes. Redundancy analysis indicated that the pH and microbial composition were the main factors that affected the variations in PMQR genes, MGEs, and CRGs, where they could explain 42.2% and 33.3% of the variation, respectively. Furthermore, intI2 may play an important role in the transfer of ARGs. We found that 80 mg kg CIP could increase the abundances of ARGs and CRGs in a soil-ryegrass pot system.
土壤中高浓度残留抗生素和抗生素抗性基因 (ARGs) 的存在可能会对健康和环境造成潜在风险。本研究调查了质粒介导的喹诺酮类耐药性 (PMQR) 基因、铜抗性基因 (CRGs) 以及同时受到铜和环丙沙星 (CIP; 0、20 或 80mgkg-1 干土) 污染的土壤黑麦草盆栽系统中的细菌群落。与第 0 天的样本相比，在刈割期（75 天后），PMQR 基因和可移动遗传元件 (MGE) 的总相对丰度在黑麦草和土壤中分别显著降低了 80-89%。与其他处理相比，用 20mgkg-1 CIP 处理的土壤中 PMQR 基因和 MGEs 的丰度降低了 63-81%，但 CRGs 的丰度增加了 18-42%。80mgkg-1 CIP 的存在通过增加 Acidobacteria 和 Thaumarchaeota 的丰度，而降低 Firmicutes 的丰度，影响了土壤中的微生物群落结构。冗余分析表明，pH 值和微生物组成是影响 PMQR 基因、MGEs 和 CRGs 变化的主要因素，它们分别可以解释 42.2%和 33.3%的变异。此外，intI2 可能在 ARGs 的转移中起重要作用。我们发现，80mgkg-1 CIP 会增加土壤黑麦草盆栽系统中 ARGs 和 CRGs 的丰度。
