HT-qPCR profiling the effect of copper on ARGs distribution characteristics in the anaerobic digestion products of swine manure
Nowadays,the problem of environmental pollution caused by antibiotics and ARGs has gradually become the research focus.In the aquaculture industry,heavy metal copper and antibiotics are the main additives in feed,but they are not fully absorbed in animals.A large number of heavy metals and microorganisms carrying ARGs will be excreted through feces,thus producing long-term selection pressure on ARGs in environmental media and increasing the risk of ARGs transmission.Anaerobic digestion is the main harmless treatment of manure,but there is still high persistence and high abundance of ARGs in its products,and the effect of copper on ARGs distribution characteristics in anaerobic digestion products are not clear.Therefore,in this study,anaerobic digestion experiments were carried out to simulate the pollution of different concentrations of copper(75 and 227 mg/L)in pig manure.Using HT-qPCR techniques to analyze distribution characteristics of ARGs,and their relationship with MGEs in fermentation products under different concentrations of copper.It was found that the relative abundance and quantity of ARGs and MGEs in the fermentation products contaminated by copper increased significantly(P＜0.05),and the total relative abundance of ARGs under 75,227 mg/L copper treatment increased by 86％and 91％respectively compared with the treatment without copper pollution.Aminoglycosides and multi-drug resistance genes were most abundant in the products,and the response of ARGs to different concentrations of copper was also different.The relative abundance of total ARGs in fermentation products contaminated by high concentration copper was higher than that in low concentration copper treatment.Generally speaking,the presence of copper in the anaerobic digestion system increased the symbiosis of ARGs and MGEs,increased the horizontal gene transfer ability of ARGs,and increased the risk of ARGs transmission and transfer in the environment.
万方数据
维普
