Liu Jian-Li, Yao Jun, Zhu Xiaozhe, Zhou De-Liang, Duran Robert, Mihucz Victor G, Bashir Safdar, Hudson-Edwards Karen A
School of Water Resources and Environment and Research Center of Environmental Science and Engineering, Sino-Hungarian Joint Laboratory of Environmental Science and Health, China University of Geosciences (Beijing), 29 Xueyuan Road, Haidian District, 100083, Beijing, China.
School of Water Resources and Environment and Research Center of Environmental Science and Engineering, Sino-Hungarian Joint Laboratory of Environmental Science and Health, China University of Geosciences (Beijing), 29 Xueyuan Road, Haidian District, 100083, Beijing, China.
Environ Pollut. 2020 Oct 12;273:115667. doi: 10.1016/j.envpol.2020.115667.
Mine tailings sites are considered as a continuous source of discharged metal(loid)s and residual organic flotation reagents. They are extremely toxic environments representing unique ecological niches for microbial communities. Mine tailings as a source of multi-resistance genes have been poorly investigated. Metagenomic analysis for four active nonferrous metal(loid) tailings sites with different environmental parameters was conducted. The abundance of Thiobacillus, able to tolerate acidity and showing iron- and sulfur/sulfide oxidation capacities, was significantly different (p < 0.05) between acid and neutral tailings sites. Correlation analyses showed that Zn, Pb, TP, Cd, and Cu were the main drivers influencing the bacterial compositions. Multi-metal resistance genes (MRGs) and antibiotic resistance genes (ARGs), such as baca and copA, were found to be co-selected by high concentrations of metal(loid)s tailings. The main contributors to different distributions of MRGs were Thiobacillus and Nocardioides genus, while genera with low abundance (<0.1%) were the main contributors for ARGs. Functional metabolic pathways related to Fe-S metabolism, polycyclic aromatic hydrocarbons (PAHs) degradation and acid stress were largely from Altererythrobacter, Lysobacter, and Thiobacillus, respectively. Such information provides new insights on active tailings with highly toxic contaminants. Short-term metal(loid) exposure of microorganism in active nonferrous metal(loid) tailings contribute to the co-occurrence of ARGs and MRGs, and aggravation of tailings acidification. Our results recommend that the management of microorganisms involved in acid tolerance and metal/antibiotic resistance is of key importance for in-suit treatment of the continuous discharge of tailings with multiple metal(loid) contaminants into impoundments.
尾矿库被认为是金属（类金属）和残留有机浮选剂的持续排放源。它们是剧毒环境，代表了微生物群落独特的生态位。作为多抗性基因来源的尾矿库尚未得到充分研究。对四个具有不同环境参数的活性有色金属（类金属）尾矿库进行了宏基因组分析。能够耐受酸性并具有铁和硫/硫化物氧化能力的硫杆菌丰度在酸性和中性尾矿库之间存在显著差异（p < 0.05）。相关性分析表明，锌、铅、总磷、镉和铜是影响细菌组成的主要驱动因素。发现多金属抗性基因（MRGs）和抗生素抗性基因（ARGs），如baca和copA，被高浓度的金属（类金属）尾矿共同选择。MRGs不同分布的主要贡献者是硫杆菌属和诺卡氏菌属，而低丰度（<0.1%）的属是ARGs的主要贡献者。与铁硫代谢、多环芳烃（PAHs）降解和酸胁迫相关的功能代谢途径分别主要来自交替赤杆菌属、溶杆菌属和硫杆菌属。这些信息为含有剧毒污染物的活性尾矿提供了新的见解。活性有色金属（类金属）尾矿中微生物的短期金属（类金属）暴露导致ARGs和MRGs的共存以及尾矿酸化的加剧。我们的结果表明，对参与耐酸性和金属/抗生素抗性的微生物进行管理对于原位处理含有多种金属（类金属）污染物的尾矿持续排放到蓄水池中至关重要。
