[Distribution Characteristics and Influencing Factors of Antibiotic Resistance Genes in Surface Sediments of Regulating Pond in South-to-North Water Transfer Pumping Station].

Abstract

As an important facility to ensure the safety of the water supply, the regulating pond of a raw water pumping station in the Tianjin Section of the middle route of the South-to-North Water Transfer Project linked the raw water from the Hanjiang River with the urban water plants. Surface sediment samples from different regions of the regulator pond were collected in summer, autumn, and winter of 2022 and spring of 2023, respectively. Metagenomic sequencing technology was used to analyze the distribution characteristics and influencing factors of antibiotic resistance genes （ARGs）, and the correlation between sediment ARGs and physicochemical indices, microbial community structure, and mobile genetic elements （MGEs） was also analyzed. The results showed that 20 antibiotic resistance types and 921 ARGs subtypes were detected in the surface sediment samples of the regulator pond. The dominant ARGs in the samples at different sampling times and sampling points were multidrug resistance, MLS, tetracycline, and glycopeptides, and the main resistance mechanism was efflux pump. Correlation analysis showed that TN, NO₃^--N, TP, and OM of sediments were significantly correlated （P<0.05） with various ARGs of the top 20 ARGs. Among the top 20 microbial genera, 19 species were significantly correlated （P<0.05） with ARGs. The MGEs types of conjugate transfer protein, recombinase, and transposase were significantly positively correlated （P<0.05） with the top 20 ARGs.