Occurrence and Distribution of Urban Dust-Associated Bacterial Antibiotic Resistance in Northern China

Abstract

The occurrence and distribution of 20 subtypes of antibiotic resistance genes (ARGs), conferring sulfonamide, tetracycline, macrolide, β-lactam, aminoglycoside, or quinolone antibiotic resistance, were investigated in urban dust samples collected from the surfaces of three megacities (Beijing, Tianjin, and Shijiazhuang) of northern China. Real-time polymerase chain reaction indicated that the abundance of ARGs and 16S rRNA genes was significantly higher in the summer than in the winter. A total of 80 antibiotic-resistant bacteria were isolated and identified, and 12 of those species were identified as opportunistic pathogens. An isolated pathogen Acinetobacter sp. was proven to be able to transfer antibiotic resistance, which highlights the potential risk that an urban dust-associated ARG poses to public health. Deep 16S rRNA sequencing indicated high heterogeneity of bacterial communities among cities in the summer, but great homogeneity in the winter. In the summer, Enterococcus, Massilia, and Anthrobacter were the most prevalent genera in Tianjin, Beijing, and Shijiazhuang, respectively. However, the most prevalent bacterial genera were Bacillus and Lactococcus in the winter. This is the first study of the occurrence and distribution of the urban dust-associated bacterial community and its associated bacterial antibiotic resistance in northern China. This study highlights the risk of dust-associated antibiotic resistance to public health.