摘要

    塑料废物在水生环境中无处不在。通常在塑料废料表面形成的生物膜可能包含抗生素抗性基因（ARG）。这项研究的重点是与从长江口采集的相关沉积物和水样相比，ARG，金属抗性基因（MRG）及其相关微生物群落在不同类型塑料上形成的生物膜中的发生和分布。结果表明，带有可见生物膜的聚丙烯（PP）和聚乙烯（PE）高度丰富，大多数被测ARGs在生物膜中的平均绝对丰度高于沉积物和水中的绝对绝对丰度，表明塑料上的生物膜可以作为生物膜发挥作用。 ARGs的储存库。而且，与其他塑料相比，PE上的生物膜具有较高的ARG相对丰度，PE上的Firmicutes可能是这些ARG的潜在宿主。此外，芽孢杆菌，分枝杆菌和假单胞菌可能是塑料的多抗性属，而tetA和tetW在PET和PP上可能具有更多的潜在宿主。金属，总磷和盐度可能是调节塑料上形成的生物膜中ARG的主要环境因素。这些结果为评估河口环境中塑料上形成的生物膜中的塑料废物和ARG引起的风险提供了新见解。 

    Plastic wastes are ubiquitous in aquatic environment. Biofilms, which are often formed on the surface of plastic waste, may contain antibiotic resistance genes (ARGs). This study focused on the occurrence and distribution of ARGs, metal resistance genes (MRGs) and their associated microbial communities in biofilms formed on different types of plastic, in comparison to associated sediment and water samples taken from the Yangtze Estuary. The results showed that polypropylene (PP) and polyethylene (PE) with visible biofilms were highly abundant, and the average absolute abundance of most tested ARGs in the biofilms was higher than that in the sediment and water, indicating that biofilms on plastics can act as a reservoir for ARGs. Moreover, the biofilms on PE had a higher relative abundance of ARGs, compared to those on other plastics, and Firmicutes on PE may be potential hosts for these ARGs. Furthermore, Bacillus, Mycobacterium and Pseudomonas may be multi-resistance genera on plastics, and tetA and tetW may have more potential hosts on PET and PP. Metals, total phosphorus and salinity may be the major environmental factors regulating ARGs in biofilms formed on plastics. The results provide new insights into evaluating the risks caused by plastic wastes and ARGs in biofilms formed on plastics in estuarine environment.

    https://www.sciencedirect.com/science/article/abs/pii/S0048969720344454