摘要

       三峡工程对该地区的水质和生态平衡产生了显着影响。特殊的工程水生环境可能是抗生素抗性基因 (ARG) 的重要储存库。本研究在地表水、土壤和沉积物中测定了与三组抗生素（四环素、磺胺类和喹诺酮类）相对应的 15 种 ARG。抗生素在水、土壤和沉积物中的总浓度范围分别为 21.55 至 536.86 ng/L、3.69 至 438.76 ng/g、15.78 至 213.84 ng/g。 ARGs 的聚合酶链反应 (PCR) 显示所有样品中存在两个磺胺类抗性基因 (sul1、sul2)、五个四环素抗性基因 (tetA、tetB、tetM、tetQ、tetG) 和 1 类整合子基因 (intI1)。并且在三个基质中，磺胺类抗性基因的相对丰度普遍高于四环素类抗性基因。在 intI1 和 ARG（tetA、tetB、tetM、tetQ、tetG、sul1、sul2）的浓度之间发现显着相关性（p < 0.05），表明 intI1 可能促进这些基因的增殖和繁殖。冗余分析(RDA)显示ARGs的分布与某些抗生素残留有关，这可能对细菌施加选择压力，从而增加ARGs的丰度。这项研究的结果可以为更好地理解和管理工程水生环境中 ARG 和相关抗生素造成的污染提供有用的信息。

       The Three Gorges Project significantly impacted water quality and ecological balance in this area. The special engineered aquatic environment could be an important reservoir for antibiotic resistance genes (ARGs). Fifteen ARGs corresponding to three groups of antibiotics (tetracyclines, sulfonamides and quinolones) were determined in surface water, soil and sediment in this study. Total concentrations of antibiotics ranged from 21.55 to 536.86 ng/L, 3.69 to 438.76 ng/g, 15.78 to 213.84 ng/g in water, soil and sediment, respectively. Polymerase chain reaction (PCR) of ARGs revealed the presence of two sulfonamide resistance genes (sul1, sul2), five tetracycline resistance genes (tetA, tetB, tetM, tetQ, tetG) and class 1 integron gene (intI1) in all samples. And the relative abundance of sulfonamide resistance genes was generally higher than tetracycline resistance genes in three matrices. Significant correlations (p < 0.05) were found between the concentrations of intI1 and ARGs (tetA, tetB, tetM, tetQ, tetG, sul1, sul2), indicating intI1 may facilitate the proliferation and propagation of these genes. Redundancy analysis (RDA) showed distribution of ARGs was related to the certain antibiotics residues, which may exert selective pressure on bacteria and thus enrich the abundance of ARGs. The results of this study could provide useful information for both better understanding and management of the contamination caused by ARGs and related antibiotics in engineered aquatic environments.

https://www.sciencedirect.com/science/article/abs/pii/S0048969718308398