摘要

为了评估抗生素抗性基因（ARG）的季节分布并探索其在不同季节和不同系统中的模式的原因，使用高通量qPCR选择和分析两个废水处理系统。使用线性判别分析（LDA）效应大小（LEfSe）来发现差异ARG（生物标记）并估计生物标记的效应大小。我们发现入流和剩余污泥样品中ARGs的总绝对丰度没有明显的季节性波动，而冬季流出样品的绝对丰度则低于入流样品。 11种差异丰富的ARG（生物标志基因，BmG）（aadA5-02，aac-6-II，cmlA1-01，cmlA1-02，blaOXA10-02，aadA-02，tetX，aadA1，ereA，qacEΔ1-01和blaTEM）在冬季样品中对夏季样品和10个BmGs（tet-32，tetA-02，aacC2，vanC-03，aac-6-I1，tetE，ermB，mefA，tnpA-07和sul2）进行验证。根据16S rRNA基因序列测定，门（门）水平细菌的相对丰度在流出水（OW）中表现出显着的季节变化，并且在家族（或属）水平上发现了生物标志物细菌（BmB）。聚球蓝细菌和vadinCA02在夏季是BmB，冬虫夏草中的球菌，乳球菌，Pelosinus，Janthinobacterium，Nitrosomonadaceae和Sterolibacterium是BmB。另外，BmB在同一季节与BmGs具有良好的相关性，这表明在季节变化期间细菌群落变化驱动ARGs的不同分布，并且LEfSe是用于发现两个或更多类别之间显着不同的ARG和细菌的急性和有效方法。

To evaluate the seasonal distribution of antibiotic resistance genes (ARGs) and explore the reason for their patterns in different seasons and different systems, two wastewater treatment systems were selected and analyzed using high-throughput qPCR. Linear discriminant analysis (LDA) effect size (LEfSe) was used to discover the differential ARGs (biomarkers) and estimate the biomarkers’ effect size. We found that the total absolute abundances of ARGs in inflows and excess sludge samples had no obvious seasonal fluctuations, while those in winter outflow samples decreased in comparison with the inflow samples. Eleven differentially abundant ARGs (biomarker genes, BmGs) (aadA5-02, aac-6-II, cmlA1-01, cmlA1-02, blaOXA10-02, aadA-02, tetX, aadA1,ereA, qacEΔ1-01, and blaTEM) in summer samples and 10 BmGs (tet-32, tetA-02, aacC2, vanC-03, aac-6-I1, tetE, ermB, mefA, tnpA - 07, and sul2) in winter samples were validated. According to 16S rRNA gene sequencing, the relative abundance of bacteria at the phylum level exhibited significant seasonal changes in outflow water (OW), and biomarker bacteria (BmB) were discovered at the family (or genus) level. Synechococcus and vadinCA02 are BmB in summer, and Trichococcus, Lactococcus, Pelosinus, Janthinobacterium,Nitrosomonadaceae and Sterolibacterium are BmB in winter. In addition, BmB have good correlations with BmGs in the same season, which indicates that bacterial community changes drive different distributions of ARGs during seasonal changes and that LEfSe is an acute and effective method for finding significantly different ARGs and bacteria between two or more classes.

https://www.sciencedirect.com/science/article/pii/S0269749117333651