Li Yi, Qin Weiwei, Xin Xiaomin, Tang Chijian, Huang Yueying, He Xinying, Chen Lixing, Yu Guo, Yu Fangming
Guangxi Key Laboratory of Environmental Processes and Remediation in Ecologically Fragile Regions, Guangxi Normal University, Guilin 541004, China; Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, Guilin 541004, China.
College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541004, China; State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
J Hazard Mater. 2025 Apr 5;487:137173. doi: 10.1016/j.jhazmat.2025.137173. Epub 2025 Jan 10.
This study examined the effects of polyethylene terephthalate (PET) nanoplastics on the rhizosphere of Oryza sativa L., focusing on dynamic changes and interactions among microbial communities, antibiotic resistance genes (ARGs) and microplastic degradation genes (MDGs). PET exposure altered the structure and function of soil microbial, enabling specific microbial groups to thrive in polluted environments. High-dose PET treatments markedly increased the abundance and dissemination of ARGs, primarily via resistance mechanisms such as antibiotic efflux and target alteration. By providing additional carbon sources and surfaces for microbial attachment, PET stimulated the growth of microorganisms harboring MDGs, resulting in an increase in MDGs abundance. The elevated expression of MDGs facilitated the propagation of ARGs, with overlapping host microorganisms suggesting that certain microbial groups exhibit dual metabolic capabilities, enabling them to endure both antibiotic and microplastic pressures. Toxic byproducts of microplastic degradation, such as mono-ethylhexyl phthalate, further promoted ARGs dissemination by increasing horizontal gene transfer frequency. Structural equation modeling revealed that PET indirectly influenced ARGs and MDGs expression by altering soil C/N ratio, available phosphorus, and enzyme activities. Thus, nanoscale PET exacerbates ecological risks to soil microbial communities by driving co-propagation of ARGs and MDGs, highlighting the persistent threat of composite pollution to agroecosystems.
本研究考察了聚对苯二甲酸乙二酯（PET）纳米塑料对水稻根际的影响，重点关注微生物群落、抗生素抗性基因（ARGs）和微塑料降解基因（MDGs）之间的动态变化及相互作用。PET暴露改变了土壤微生物的结构和功能，使特定微生物类群能在污染环境中繁衍。高剂量PET处理显著增加了ARGs的丰度和传播，主要通过抗生素外排和靶点改变等抗性机制。通过为微生物附着提供额外的碳源和表面，PET刺激了携带MDGs的微生物生长，导致MDGs丰度增加。MDGs的高表达促进了ARGs的传播，宿主微生物重叠表明某些微生物类群具有双重代谢能力，使其能够耐受抗生素和微塑料压力。微塑料降解的有毒副产物，如邻苯二甲酸单乙基己酯，通过增加水平基因转移频率进一步促进了ARGs传播。结构方程模型显示，PET通过改变土壤碳氮比、有效磷和酶活性间接影响ARGs和MDGs表达。因此，纳米级PET通过推动ARGs和MDGs共同传播加剧了对土壤微生物群落的生态风险，凸显了复合污染对农业生态系统的持续威胁。
