Adyari Bob, Liao Xin, Yan Xiuhang, Qiu Yuxin, Grossart Hans-Peter, Li Laiyi, Yu Tao, Mao Guannan, Liu Keshao, Su Jiangqian, Liu Yongqin, Hu Anyi
CAS Key Laboratory of Urban pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, PR China; Department of Environmental Engineering, Universitas Pertamina, Jakarta 12220, Indonesia.
CAS Key Laboratory of Urban pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
Water Res. 2025 Sep 15;284:123887. doi: 10.1016/j.watres.2025.123887. Epub 2025 May 22.
The spread of anthropogenic genes, such as antibiotic resistance genes (ARGs), mobile genetic elements (MGEs), virulence factor genes (VFGs), and antibiotic-resistant bacteria (ARBs), is a growing public health concern. However, the role of anthropogenic activities in the dissemination of these genes and bacteria in Tibetan Plateau rivers is still unclear. In this study, we analyzed 138 metagenomic samples from water and sediment across nine Tibetan rivers, along with sewage samples from 21 wastewater treatment plants (WWTPs), at both the gene and contig levels, to investigate the spread of the sewage-enriched genes and their bacterial hosts (contigs) in Tibetan rivers. Overall, sewage input was positively correlated with increased the abundance of an average 56 % and 17 % of detected genes in water and sediment, respectively. However, FEAST source tracking analysis revealed that the overall contribution of sewage across all rivers was significantly lower than that of water and sediment. Additionally, sewage's impact varied across rivers, with the Yarlung Zangbo, the largest river, exhibiting limited influence despite receiving inputs from smaller rivers and WWTPs. Neutral community model (NCM) suggested that neutral processes and negative selection predominantly governed the spread of majority of highly abundant sewage-enriched genes and contigs, suggesting restricted environmental spread. In contrast, a subset of genes over-represented relative to neutral expectations (above-neutral prediction) showed lower overall abundance but higher richness, potentially reflecting selection that favor their retention in certain downstream environments. Furthermore, sewage-enriched genes and contigs in water, regardless of their community assembly processes, were linked to microbial interaction modules dominated by microeukaryotic groups associated with sewage, including consumer protists (ciliate), human parasites (e.g., Naegleria), algae, and fungi. These interactions may facilitate the dissemination of antimicrobial resistance in aquatic environments, though this pattern was less pronounced in sediment.
人为基因的传播，如抗生素抗性基因（ARGs）、移动遗传元件（MGEs）、毒力因子基因（VFGs）和抗生素抗性细菌（ARBs），日益引起公众对健康的关注。然而，人为活动在青藏高原河流中这些基因和细菌传播中的作用仍不清楚。在本研究中，我们在基因和重叠群水平上分析了来自九条西藏河流的水和沉积物的138个宏基因组样本，以及来自21个污水处理厂（WWTPs）的污水样本，以研究富含污水的基因及其细菌宿主（重叠群）在西藏河流中的传播。总体而言，污水输入分别与水中和沉积物中平均56%和17%的检测基因丰度增加呈正相关。然而，FEAST源追踪分析表明，所有河流中污水的总体贡献显著低于水和沉积物。此外，污水的影响因河流而异，最大的河流雅鲁藏布江尽管接收了较小河流和污水处理厂的输入，但其影响有限。中性群落模型（NCM）表明，中性过程和负选择主要控制了大多数高度丰富的富含污水的基因和重叠群的传播，表明环境传播受到限制。相比之下，相对于中性预期（高于中性预测）过度代表的一部分基因显示出较低的总体丰度但较高的丰富度，这可能反映了有利于它们在某些下游环境中保留的选择。此外，水中富含污水的基因和重叠群，无论其群落组装过程如何，都与以与污水相关的微型真核生物群体为主的微生物相互作用模块相关联，包括消费者原生生物（纤毛虫）、人类寄生虫（如耐格里属）、藻类和真菌。这些相互作用可能促进了水生环境中抗菌抗性的传播，尽管这种模式在沉积物中不太明显。
