Zhao Jun, Duan Guilan, Zhu Dong, Li Jianzhong, Zhu Yongguan
Laboratory for Chemical Environmental Risk Assessment, 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.
Environ Pollut. 2024 Feb 1;342:123010. doi: 10.1016/j.envpol.2023.123010. Epub 2023 Nov 25.
Within human-influenced landscapes, pesticides cooccur with a variety of antibiotic stressors. However, the relationship between pesticides removal process and antibiotic resistance gene variation are not well understood. This study explored pesticide (topramezone, TPZ) and antibiotic (polymyxin E, PME) co-contamination using liquid chromatography-tandem mass spectrometry (LC-MS/MS), bacterial-16 S rRNA sequencing and high-throughput quantitative polymerase chain reaction (HT-qPCR) in a soil-earthworm-maize system. After incubating soil for 28 days with TPZ and PME (10 mg kg dry weight), earthworm weight-gain, mortality rates, and maize plant weight-gain only differed slightly, but height-gain significantly decreased. PME significantly increased TPZ-removal in the soil. Accumulation of TPZ in earthworm's tissues may pose potential risks in the food chain. Combined pollution altered the microbial community structure and increased the abundance of functional microorganisms involved in aromatic compound degradation. Furthermore, maize rhizosphere can raise resistance genes, however earthworms can reduce resistance genes. Co-contamination increased absolute abundance of mobile genetic elements (MGEs) in bulk-soil samples, antibiotic resistance genes (ARGs) in skin samples and number of ARGs in bulk-soil samples, while decreased absolute abundance of transposase gene in bulk-soil samples and number of ARGs in rhizosphere-soil samples. Potential hosts harbouring ARGs may be associated with the antagonistic effect during resistance and detoxification of TPZ and PMB co-occurrence. These findings provide insights into the mechanism underlining pesticide removal regarding occurrence of ARGs in maize agroecosystem.
在受人类影响的景观中，农药与多种抗生素应激源同时存在。然而，农药去除过程与抗生素抗性基因变异之间的关系尚未得到充分理解。本研究在土壤-蚯蚓-玉米系统中，使用液相色谱-串联质谱法（LC-MS/MS）、细菌16S rRNA测序和高通量定量聚合酶链反应（HT-qPCR），探究了农药（甲基磺草酮，TPZ）和抗生素（多粘菌素E，PME）的共同污染情况。用TPZ和PME（10毫克/千克干重）对土壤进行28天的培养后，蚯蚓的体重增加、死亡率以及玉米植株的体重增加仅有轻微差异，但株高增加显著降低。PME显著增加了土壤中TPZ的去除率。TPZ在蚯蚓组织中的积累可能会在食物链中带来潜在风险。复合污染改变了微生物群落结构，并增加了参与芳香族化合物降解的功能微生物的丰度。此外，玉米根际会增加抗性基因，而蚯蚓则会减少抗性基因。共同污染增加了土壤样本中移动遗传元件（MGEs）的绝对丰度、皮肤样本中抗生素抗性基因（ARGs）的数量以及土壤样本中ARGs的数量，同时降低了土壤样本中转座酶基因的绝对丰度和根际土壤样本中ARGs的数量。携带ARGs的潜在宿主可能与TPZ和PME共存时的抗性和解毒拮抗作用有关。这些发现为玉米农业生态系统中ARGs出现情况下农药去除的潜在机制提供了见解。
