摘要
      微塑料在淡水、沿海和深海沉积物中普遍存在。然而，微塑料对沉积微生物生态系统的影响尚未得到充分报道。利用16S rRNA基因和宏基因组测序，我们研究了沿海沉积污泥微生物群落结构、组成、功能、抗生素抗性基因（ARGs）的组装和繁殖对不同微塑料的反应。微塑料暴露后，硝化菌、反硝化菌和氨氧化剂发生了显著变化。PE和PET处理组中NO3−、NO2−和NH4+的浓度与相应功能属的相对丰度一致。PE、PET和PVC组中抗生素外排ARGs丰度的增加与外排泵系统的促进直接相关。活性氧（ROS）的产生、ROS介导的DNA损伤以及微塑料暴露诱导的应激反应增加可能是促进ARGs转移的原因。在微塑料的压力下，主要的氮降解属和ARGs宿主的组装趋于确定性，表明微塑料的选择性作用。
Abstract
Microplastics are prevalent in freshwater, coastal, and deep ocean sediments. However, the effects of microplastics on sedimentary microbial ecosystems have not been well reported. Using 16S rRNA gene and metagenomic sequencing, we investigated coastal sedimentary sludge microbial community structure, composition, function, assembly, and propagation of antibiotic resistance genes (ARGs) in response to different microplastics. The nitrifier, denitrifiers and ammonia oxidizer were significantly altered upon microplastics exposure. The concentrations of NO3−, NO2−, and NH4+ in PE and PET treated groups were in consistent with relative abundances of corresponding functional genera. The increased antibiotic efflux ARGs abundance in PE, PET, and PVC groups was directly related to the promoted efflux pump system. Reactive oxygen species (ROS) production, ROS-mediated DNA damage, and increased stress response induced by microplastics exposure might be the reason for the promotion of ARGs transfer. Assembly of dominate nitrogen degrading genus and ARGs hosts tended to be deterministic under the pressure of microplastics, indicating the selective effect of microplastics.

https://www.sciencedirect.com/science/article/abs/pii/S138589472205673X