College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China.
College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China.
Environ Pollut. 2021 Jan 1;268(Pt A):115796. doi: 10.1016/j.envpol.2020.115796. Epub 2020 Oct 21.
Animals living in urban river systems play critical roles in the dissemination of microbiome and antibiotic resistance that poses a strong threat to public health. This study provides a comprehensive profile of microbiota and antibiotic resistance genes (ARGs) of sharpbelly (Hemiculter leucisculus) and the surrounding water from five sites along the Ba River. Results showed Proteobacteria, Firmicutes and Fusobacteria were the dominant bacteria in gut of H. leucisculus. With the aggravation of water pollution, bacterial biomass of fish gut significantly decreased and the proportion of Proteobacteria increased to become the most dominant phylum eventually. To quantify the contributions of influential factors on patterns of gut microbiome with structural equation model (SEM), water bacteria were confirmed to be the most stressors to perturb fish gut microbiome. SourceTracker model indicated that deteriorating living surroundings facilitated the invasion of water pathogens to fish gut eco-environments. Additionally, H. leucisculus gut is an important reservoir of ARGs in Ba River with relative abundance up to 9.86 × 10/copies. Among the ARGs, tetracycline and quinolone resistance genes were detected in dominant abundance. Deterioration of external environments elicited the accumulation of ARGs in fish gut. Intestinal class I integron, environmental heavy metal residues and gut bacteria were identified as key drivers of intestinal ARGs profiles in H. leucisculus. Analysis of SEM and co-occurrence patterns between ARGs and bacterial hosts indicated that class I integron and bacterial community played vital roles in ARGs transmission through water-fish pathway. In general, this study highlighted hazards of water contamination to microbiome and ARGs in aquatic animals and provided a new perspective to better understand the bacteria and ARGs dissemination in urban river ecosystems.
生活在城市河流系统中的动物在微生物组和抗生素耐药性的传播中发挥着关键作用，这对公共健康构成了强烈威胁。本研究全面描绘了贝河流域五个地点的尖嘴（Hemiculter leucisculus）及其周围水体的微生物组和抗生素耐药基因（ARGs）。结果表明，厚壁菌门、拟杆菌门和梭杆菌门是尖嘴肠道中的优势细菌。随着水污染的加剧，鱼类肠道中的细菌生物量显著减少，而变形菌门的比例增加，最终成为最主要的门。为了通过结构方程模型（SEM）量化影响因素对肠道微生物组模式的贡献，水细菌被确认为干扰鱼类肠道微生物组的最主要压力因素。SourceTracker 模型表明，恶化的生活环境促进了水病原体入侵鱼类肠道生态环境。此外，尖嘴肠道是贝河流域 ARGs 的重要储存库，相对丰度高达 9.86×10/copies。在 ARGs 中，检测到四环素和喹诺酮耐药基因占主导地位。外部环境的恶化导致鱼类肠道中 ARGs 的积累。肠道 I 类整合子、环境重金属残留和肠道细菌被鉴定为尖嘴肠道中肠道 ARGs 谱的关键驱动因素。SEM 分析和 ARGs 与细菌宿主之间的共现模式表明，I 类整合子和细菌群落通过水-鱼途径在 ARGs 传播中发挥着重要作用。总的来说，本研究强调了水污染对水生动物微生物组和 ARGs 的危害，并为更好地理解城市河流生态系统中细菌和 ARGs 的传播提供了新的视角。
