Antibiotic resistance genes (ARGs) in microorganisms and their indications for the nitrogen/sulfur cycle in the East China Sea sediments

Antibiotic resistance genes (ARGs) are emerging environmental pollutants, posing an escalating threat to public health and environmental security worldwide. However, the relationship between ARGs and microbial communities in the environment, as well as their ecological effects on the microbe-mediated materials cycle remain unclear. In this study, we investigated the spatial distribution pattern, influence mechanism, relationship with microorganisms, and their effects on the elemental cycling of ARGs in East China Sea sediments. The results showed that temperature caused a latitudinal gradient in the distribution of ARGs. The sulfonamide and quinolone ARGs were characterized by a distribution pattern of “higher in the south and lower in the north” with a boundary of 29 °N, while tetracycline and macrolide ARGs have the opposite distribution patterns. The spatial variation of environmental parameters shaped the differences in microbial abundance and diversity. Sulfonamide and quinolone ARGs were greatly affected by temperature, intI1, microbial composition, and abundance, while tetracyclines and macrolides ARGs were mainly affected by microbial alpha diversity index and NO₂^-. ARGs and intI1 were synchronously significantly correlated with nitrogen and sulfur cycle functional genes, indicating that microorganisms with ARGs can integrate nitrogen and sulfur cycle functional genes through intI1, thereby promoting or inhibiting nitrogen and sulfur cycle. This study will provide an important scientific basis for exploring the pollution control and ecological risk assessment of ARGs in sediments.