摘要
      铊（Tl）被广泛用于各种行业，这增加了泄漏到环境中的风险。由于Tl具有剧毒，它会对人类健康和生态系统造成巨大危害。为了探讨淡水沉积物微生物对Tl突然泄漏的反应，利用宏基因组技术阐明了河流沉积物中微生物群落组成和功能基因的变化。Tl污染可能对微生物群落的组成和功能产生深远影响。变形杆菌在受污染的食物中仍然占主导地位，表明它对Tl污染有很强的抵抗力，蓝藻也表现出一定的抵抗力。Tl污染对抗性基因也有一定的筛选作用，并影响抗性基因的丰度。金属抗性基因（MRGs）和抗生素抗性基因（ARGs）在泄漏现场附近富集，污染现场的Tl浓度相对较低。当Tl浓度较高时，筛选效果不明显，抗性基因甚至变低。此外，核磁共振成像与ARGs之间存在显著相关性。此外，共现网络分析表明，鞘翅目昆虫与抗性基因的联系最多，表明它是抗性基因最大的潜在宿主。这项研究为突然严重的Tl污染后微生物群落的组成和功能的变化提供了新的见解。
Abstract
Thallium (Tl) is widely used in various industries, which increases the risk of leakage into the environment. Since Tl is highly toxic, it can do a great harm to human health and ecosystem. In order to explore the response of freshwater sediment microorganisms to sudden Tl spill, metagenomic technique was used to elucidate the changes of microbial community composition and functional genes in river sediments. Tl pollution could have profound impacts on microbial community composition and function. Proteobacteria remained the dominance in contaminated szediments, indicating that it had a strong resistance to Tl contamination, and Cyanobacteria also showed a certain resistance. Tl pollution also had a certain screening effect on resistance genes and affected the abundance of resistance genes. Metal resistance genes (MRGs) and antibiotic resistance genes (ARGs) were enriched at the site near the spill site, where Tl concentration was relatively low among polluted sites. When Tl concentration was higher, the screening effect was not obvious and the resistance genes even became lower. Moreover, there was a significant correlation between MRGs and ARGs. In addition, co-occurrence network analysis showed that Sphingopyxis had the most links with resistance genes, indicating that it was the biggest potential host of resistance genes. This study provided new insight towards the shifts in the composition and function of microbial communities after sudden serious Tl contamination.

https://www.sciencedirect.com/science/article/abs/pii/S0048969723017205