摘要

    抗生素抗性基因（ARG）被认为是新兴的遗传污染物，正在威胁全球的公共健康。 ARGs有两种存在形式：细胞内ARGs（i-ARGs）和细胞外ARGs（e-ARGs），在好氧颗粒污泥（AGS）系统中很少出现它们的出现和扩散模式。结果表明，i-ARGs和e-ARGs均富集，但在AGS培养过程中具有不同的转移方式，e-ARGs具有较高的生长速率。富含AGS的大多数功能性细菌可能在i / e-ARG的积累中起重要作用，它们的寡聚型可能是分类单元和i / e-ARG之间相关性不同的关键原因。 E-ARG可能会从i-ARG转变而来，并主要由e-整合子携带，并且观察到e-ARG之间共存的三个主要模块。环境因素和细菌群落的共同作用是造成e-ARGs转变方式的主要因素（35.43％）。这项研究对有氧制粒过程中i / e-ARGs的迁移和积累进行了解释，并提供了在实际AGS应用过程中i / e-ARGs传播的一些有意义的理解。

    Antibiotic resistance genes (ARGs) were considered as emerging genetic contaminants, which were threatening public health worldwide. ARGs had two forms of existence: intracellular ARGs (i-ARGs) and extracellular ARGs (e-ARGs), and their emergence and spread patterns were rarely revealed in aerobic granular sludge (AGS) system. The results showed that both i-ARGs and e-ARGs were enriched but had different shift patterns during AGS cultivation process, and e-ARGs had higher growth rate. Most functional bacteria enriched in AGS might play important roles in accumulating of i/e-ARGs, and their oligotypes might be the key reason for the different correlations between taxa and i/e-ARGs. E-ARGs might be transformed from i-ARGs and mainly carried by e-integrons, and three major modules of co-occurrence among e-ARGs were observed. The combined action of environmental factors and bacterial community contributed most (35.43%) to the shift pattern of e-ARGs. This study deciphered the migrations and accumulations of i/e-ARGs during aerobic granulation process, and provided several meaningful comprehensions on i/e-ARGs dissemination during practical AGS application.

    https://www.sciencedirect.com/science/article/abs/pii/S1385894720338572