The bacterial microbiota in florfenicol contaminated soils: The antibiotic resistome and the nitrogen cycle. (April 2020) - Wang, Mei
Abstract: Soil antibiotic resistome and the nitrogen cycle are affected by florfenicol addition to manured soils but their interactions have not been fully described. In the present study, antibiotic resistance genes (ARGs) and nitrogen cycle genes possessed by soil bacteria were characterized using real-time fluorescence quantification PCR (qPCR) and metagenomic sequencing in a short-term (30 d) soil model experiment. Florfenicol significantly changed in the abundance of genes conferring resistance to aminoglycosides, β-lactams, tetracyclines and macrolides. And the abundance of Sphingomonadaceae, the protein metabolic and nitrogen metabolic functions, as well as NO reductase, nitrate reductase, nitrite reductase and N2 O reductase can also be affected by florfenicol. In this way, ARG types of genes conferring resistance to aminoglycosides, β-lactamases, tetracyclines, colistin, fosfomycin, phenicols and trimethoprim were closely associated with multiple nitrogen cycle genes. Actinobacteria, Chlorobi, Firmicutes, Gemmatimonadetes, Nitrospirae, Proteobacteria and Verrucomicrobia played an important role in spreading of ARGs. Moreover, soil physicochemical properties were important factors affecting the distribution of soil flora. This study provides a theoretical basis for further exploration of the transmission regularity and interference mechanism of ARGs in soil bacteria responsible for nitrogen cycle. Graphical abstract: Image 1 Highlights: The relationship of antibiotic resistome and nitrogen cycle were studied in soil. The abundance of Sphingomonadaceae was reduced 54–56% with florfenicol exposure. The soil antibiotic resistome responded rapidly with florfenicol exposure. Protein metabolic functions in our test soils were decreased by florfenicol. Abstract : Different responses of soil nitrogen cycle microorganisms including abundance, function and metabolism to various concentration of florfenicol may have been due to the presence of ARGs.