Microplastics existing widely in different matrices have been regarded as a reservoir for emerging contaminants. Mariculture systems have been observed to host microplastics and antibiotic resistance genes (ARGs). However, more information on proliferation of ARGs and metal resistance genes (MRGs) in mariculture system at the presence of microplastics is needed. This study used metagenomic analysis to investigate the distribution of ARGs and MRGs in water and microplastics of a typical mariculture pond. Total 18 types including 174 subtypes of ARGs were detected with the total relative abundances of 1.22/1.25 copies per 16S rRNA copy for microplastics/water. Chloramphenicol resistance genes were the dominant ARGs with the abundance of 0.35/0.42 copies per 16S rRNA copy for microplastics/water. Intergron intI1 was dominant gene among 6 detected mobile genetic elements (MGEs) with the abundance of 75.46/68.70 copies per 16S rRNA copy for water/microplastics. Total 9 types including 46 subtypes of MRGs were detected with total abundance of 5.02 × 10²/6.39 × 10² copies per 16S rRNA copy for water/ microplastics while genes resistant to copper and iron served as the dominant MRGs. Proteobacteria, Bacteroidetes, and Actinobacteria accounted for 84.2%/89.5% of total microbial community in microplastics/water. ARGs with relatively high abundance were significantly positively related to major genera, MGEs, and MRGs. Microplastics in mariculture system could enrich most of MRGs and some ARGs to serve as potential reservoir for these pollutants. The findings of this study will provide important information on resistance gene pollution at presence of microplastics in the mariculture system for further proposing suitable strategy of environmental management.

广泛存在于不同基质中的微塑料已被视为新出现污染物的储存库。已经观察到海水养殖系统含有微塑料和抗生素抗性基因 (ARG)。然而，需要更多关于在微塑料存在下海水养殖系统中 ARG 和金属抗性基因 (MRG) 增殖的信息。本研究使用宏基因组分析来研究 ARGs 和 MRGs 在典型海水养殖池塘的水和微塑料中的分布。共检测到 18 种类型，包括 174 个 ARG 亚型，微塑料/水的总相对丰度为 1.22/1.25 个拷贝/16S rRNA 拷贝。氯霉素抗性基因是显性 ARG，对于微塑料/水，每 16S rRNA 拷贝的丰度为 0.35/0.42 拷贝。Intergron INTI1 是 6 个检测到的移动遗传元件 (MGE) 中的显性基因，对于水/微塑料，每 16S rRNA 拷贝的丰度为 75.46/68.70 拷贝。共检测到9种类型，包括46个MRGs亚型，水/微塑料的16S rRNA拷贝的总丰度为5.02×10 ² /6.39×10 ^{2 个}拷贝，而对铜和铁具有抗性的基因作为优势MRGs。变形菌、拟杆菌和放线菌占微塑料/水中总微生物群落的 84.2%/89.5%。丰度较高的 ARGs 与主要属、MGEs 和 MRGs 呈显着正相关。海水养殖系统中的微塑料可以富集大部分MRGs和一些ARGs，作为这些污染物的潜在储存库。本研究的结果将为海水养殖系统中存在微塑料的抗性基因污染提供重要信息，以进一步提出合适的环境管理策略。