摘要
      环境中的抗生素抗性基因（ARGs）越来越受到人们的关注。然而，没有关于城市下垫面沉积物中ARGs污染的可用文献。在本研究中，选择南京（中国）周围商业公共广场的沉积物进行目标ARGs分布调查，结果表明，颗粒中的细胞内ARGs（iARGs）占主导地位，其相对丰度依次为4.82×10−2拷贝/16S rRNA（<0.063 mm）、4.18×，3.70×10−2拷贝/16S rRNA（0.25–0.5 mm）、3.44×10−1拷贝/16S r RNA（0.5–1 mm）、3.20×10–2拷贝/16S rRNA（0.125–0.25 mm）和9.53×10−3拷贝/16S r RNA（1–2 mm），这与细胞外ARG（eARGs）不同。街道清扫对ARGs水平的影响表明，不同地点沉积物中iARGs和eARGs的物种和相对丰度与相应的种群密度不一致。ARGs与优势细菌群落之间的相关性表明，厚壁菌门和拟杆菌门都与ARGs呈正相关（P<0.01）。太阳紫外线消毒的作用表明，紫外线照射可以使抗生素耐药性细菌（ARB）稍微失活，降低0.5–1.0 log，这意味着太阳照射后发生ARB的风险相当大。我们的研究结果表明，它需要更有效的清扫模式来清洁小颗粒物（<0.25 mm），并对ARGs潜在宿主（如厚壁菌门和Blastocatella）进行更高的消毒。
Abstract
Increasing attention has been paid to antibiotic resistance genes (ARGs) in environments. However, no available literature could be found on ARGs contamination in urban underlying surface sediments. In this study, sediments from commercial public squares around Nanjing (China) were selected for the investigation of target ARGs distribution, showing that intracellular ARGs (iARGs) in particles were the dominant with their relative abundances in descending order of 4.82 × 10−2 copies/16S rRNA (<0.063 mm), 4.18 × 10−2 copies/16S rRNA (0.063–0.125 mm), 3.70 × 10−2 copies/16S rRNA (0.25–0.5 mm), 3.44 × 10−2 copies/16S rRNA (0.5–1 mm), 3.20 × 10−2 copies/16S rRNA (0.125–0.25 mm) and 9.53 × 10−3 copies/16S rRNA (1–2 mm), which was different with that of extracellular ARGs (eARGs). The influence of street sweeping on ARGs levels indicated that the species and relative abundances for both iARGs and eARGs in sediments from different sites were not consistent with the corresponding population densities. The correlation between ARGs and dominant bacterial communities implied that both Firmicutes and Bacteroidetes were positively correlated with ARGs (P < 0.01). The role of solar UV disinfection demonstrated that UV irradiation could inactivate antibiotic resistance bacteria (ARB) slightly with 0.5–1.0 log reduction, implying a considerable risk of ARB after solar irradiation. Our results suggested that it would need the more effective sweeping modes for the cleaning of small particles (<0.25 mm) and the higher disinfection to ARGs potential hosts (like Firmicutes and Blastocatella).

https://www.sciencedirect.com/science/article/abs/pii/S0048969722028273