渗滤液中聚苯乙烯微塑料表面老化行为及抗性基因的富集规律

Surface Aging Behavior of Polystyrene Microplastics in Leachate and Enrichment of Antibiotic Resistance Genes

以聚苯乙烯(PS)微塑料(MPs)为例,分析其在渗滤液中的老化规律以及老化过程对抗性基因(ARGs)的富集效应及富集机制。结果表明,90 d老化后PS微塑料比表面积增大、含氧基团增加。渗滤液中的PS微塑料表面可选择性富集ARGs,并且随着老化时间延长富集程度增加。进一步采用微生物属‒ARGs共相关网络和基因表达等来揭示PS微塑料富集ARGs的机制,证实PS微塑料表面形成的生态位具有更为密切的ARGs‒微生物关联关系,并且参与ARGs调控的基因表达水平较高。

Polystyrene(PS)microplastics(MPs)were taken as an example to analyze its aging pattern in leachate,as well as the enrichment effect of aging process on antibiotic resistance genes(ARGs)and the enrichment mechanism.The results show that the specific surface area and oxygen-containing groups of PS microplastics increase after 90 d of aging.ARGs can be selectively enriched on the surface of PS microplastics in leachate,and the degree of enrichment increases with the aging time.Furthermore,the genus-ARGs co-correlation network and the gene expression prediction were used to reveal the mechanism of ARGs enrichment.It is found that the niche formed on the surface of PS microplastics has closer ARGs-microbe correlation,and the expression level of genes involved in ARGs spread is higher.