State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
J Environ Sci (China). 2023 Mar;125:701-711. doi: 10.1016/j.jes.2022.02.027. Epub 2022 Feb 27.
Paddy soils are potential hotspots of combined contamination with arsenic (As) and antibiotics, which may induce co-selection of antibiotic resistance genes (ARGs) and As biotransformation genes (ABGs), resulting in dissemination of antimicrobial resistance and modification in As biogeochemical cycling. So far, little information is available for these co-selection processes and specific patterns between ABGs and ARGs in paddy soils. Here, the 16S rRNA amplicon sequencing and high-throughput quantitative PCR and network analysis were employed to investigate the dynamic response of ABGs and ARGs to As stress and manure application. The results showed that As stress increased the abundance of ARGs and mobile genetic elements (MGEs), resulting in dissemination risk of antimicrobial resistance. Manure amendment increased the abundance of ABGs, enhanced As mobilization and methylation in paddy soil, posing risk to food safety. The frequency of the co-occurrence between ABGs and ARGs, the host bacteria carrying both ARGs and ABGs were increased by As or manure treatment, and remarkably boosted in soils amended with both As and manure. Multidrug resistance genes were found to have the preference to be co-selected with ABGs, which was one of the dominant co-occurring ARGs in all treatments, and manure amendment increased the frequency of Macrolide-Lincosamide-Streptogramin B resistance (MLSB) to co-occur with ABGs. Bacillus and Clostridium of Firmicutes are the dominant host bacteria carrying both ABGs and ARGs in paddy soils. This study would extend our understanding on the co-selection between genes for antibiotics and metals, also unveil the hidden environmental effects of combined pollution.
水稻土是砷（As）和抗生素复合污染的潜在热点，这可能导致抗生素耐药基因（ARGs）和砷生物转化基因（ABGs）的共选择，从而导致抗微生物耐药性的传播和 As 生物地球化学循环的改变。到目前为止，对于这些共选择过程以及水稻土中 ABGs 和 ARGs 之间的特定模式，我们知之甚少。在这里，我们采用 16S rRNA 扩增子测序、高通量定量 PCR 和网络分析来研究 ABGs 和 ARGs 对 As 胁迫和粪肥应用的动态响应。结果表明，As 胁迫增加了 ARGs 和移动遗传元件（MGEs）的丰度，导致抗微生物耐药性的传播风险。粪肥添加增加了 ABGs 的丰度，增强了水稻土中 As 的迁移和甲基化，对食品安全构成威胁。ABGs 和 ARGs 之间的共发生频率、同时携带 ARGs 和 ABGs 的宿主细菌，在 As 或粪肥处理下增加，并在同时添加 As 和粪肥的土壤中显著增加。发现多药耐药基因与 ABGs 有共选择的偏好，这是所有处理中主要共发生的 ARGs 之一，粪肥添加增加了 Macrolide-Lincosamide-Streptogramin B 耐药（MLSB）与 ABGs 共发生的频率。Firmicutes 的芽孢杆菌属和梭菌属是水稻土中同时携带 ABGs 和 ARGs 的主要宿主细菌。本研究将扩展我们对抗生素和金属基因共选择的理解，也揭示了复合污染的潜在环境效应。
