Engineering Research Center of Groundwater Pollution Control and Remediation, Ministry of Education, College of Water Sciences, Beijing Normal University, No 19, Xinjiekouwai Street, Beijing 100875, PR China.
Engineering Research Center of Groundwater Pollution Control and Remediation, Ministry of Education, College of Water Sciences, Beijing Normal University, No 19, Xinjiekouwai Street, Beijing 100875, PR China.
Water Res. 2024 Dec 1;267:122473. doi: 10.1016/j.watres.2024.122473. Epub 2024 Sep 18.
The discharge of wastewater into rivers can lead to resistome coalescence, thereby enhancing the spread risk of antibiotic resistance genes (ARGs) through mixing of exogenous wastewater resistome communities with indigenous riverine communities. At present, the understanding on the role of resistome community coalescence in the dissemination of ARGs is still very limited, and little is known about the process and its ecological implications. To bridge the gap, this study has conducted field-based surveys and microcosm experiments to deeply dissect the coalescence of resistome community in wastewater within river environment, utilizing genome-centric metagenomic analysis approach. The field investigation suggests resistome coalescence enhances the abundance and diversity of ARGs in the receiving river. Furthermore, the microcosm experiments reveal the effect of mixing ratio on resistome coalescence in the water-sediment system and decipher the temporal attenuation dynamics of the coalesced resistome in the environment. The results show the higher proportion of wastewater has a greater impact on ARGs in the water, whereas the effect of mixing ratio is lesser in the sediments. Temporally, the source-specific ARGs originating from wastewater exhibit decreasing trends over the experimental duration, and relatively, the attenuation in the water is more pronounced than that in the sediments. Interestingly, natural light not only facilitates the attenuation of ARGs in the water but may also induce their deposition at the water-sediment interface. Variance partitioning analyses suggest the microbiome, mobilome, and abiotic factors collectively shape the coalescence of the resistome communities in the environment. The study provides empirical evidence on resistome coalescence in river systems, which is instrumental in gaining a better understanding of the spread mechanism of ARGs in the environment.
污水排入河流会导致耐药组的合并，从而通过混合外源废水耐药组群落与本土河流群落，增强抗生素耐药基因 (ARGs) 的传播风险。目前，人们对抗耐药组群落合并在 ARGs 传播中的作用的认识还非常有限，对这一过程及其生态意义知之甚少。为了弥补这一空白，本研究利用基于基因组的宏基因组分析方法，进行了基于现场的调查和微宇宙实验，以深入剖析废水在河流环境中的耐药组群落的合并过程。现场调查表明，耐药组的合并会增加受纳河中 ARGs 的丰度和多样性。此外，微宇宙实验揭示了混合比对水-沉积物系统中耐药组合并的影响，并阐明了环境中合并耐药组的时间衰减动态。结果表明，较高比例的废水对水中的 ARGs 影响更大，而混合比对沉积物中耐药组的影响较小。从时间上看，源于废水的特定来源的 ARGs 在实验过程中呈下降趋势，而水中的衰减比沉积物中更为明显。有趣的是，自然光不仅促进了水中 ARGs 的衰减，还可能促使它们在水-沉积物界面沉积。方差分解分析表明，微生物组、移动组和非生物因素共同塑造了环境中耐药组群落的合并。该研究提供了河流系统中耐药组合并的实证证据，有助于更好地理解 ARGs 在环境中的传播机制。
