摘要

       抗生素耐药基因（ARGs）被认为是与人类活动有关的新兴污染物。城市水环境容易导致ARGs的持续和流行。在本研究中，我们调查了2016年干湿季珠海市饮用水源、城市河流和沿海地区沉积物样品中ARGs和整合酶基因的发生和分布。结果表明，sulII抗磺胺基因的检出率最高（85.71%），其平均浓度在旱季和雨季均最高（分别为3.78×107和9.04×107拷贝/g底泥），其次是tetC、tetO、tetA、ermB、dfrA1和blaPSE-1。从时间上看，丰水期总ARGs浓度可能高于枯水期；从空间上看，饮用水源地总ARGs浓度明显低于城市河流及附近沿海地区，表明不同程度的人为影响和由此产生的健康风险。在所有雨季而非旱季样品中，intI1与各定量ARG均呈显著正相关，说明夏季气温升高、降雨量增加可能对ARG的传播产生积极影响，尤其是intI1基因和Ⅰ类整合子介导的影响。

       Antibiotic resistance genes (ARGs) are regarded as emerging contaminants related with human activities. Aquatic environments of an urban city are apt for the persistence and prevalence of ARGs. In this study, we investigated the occurrence and distribution of ARGs and integrase genes in the sediment samples collected from drinking water sources, urban rivers, and coastal areas of Zhuhai, China, in the dry and wet seasons of 2016. The results show that sulfonamide resistance gene of sulII was present at the highest detection frequency (85.71%); and its average concentrations were also the highest in both dry and wet seasons (3.78 × 10⁷ and 9.04 × 10⁷ copies/g sediment, respectively), followed by tetC, tetO, tetA, ermB, dfrA1, and bla_PSE-1. Temporally, the concentrations of total ARGs in the wet season were likely higher than those in the dry season; and spatially, the concentrations of total ARGs in the drinking water sources were substantially lower than those in the urban rivers and nearby coastal areas, indicating the different degrees of anthropogenic impact and consequent health risks. Positive correlations were found between intI1 and each quantitative ARG in all wet season samples rather than dry season samples, which suggested higher temperature and more rain in summer might have positive influences on ARG dissemination, especially that mediated by intI1 gene and class I integrons.

       https://link.springer.com/article/10.1007/s11356-018-2664-0