Metagenomics reveals that temperature predicts a small proportion of antibiotic resistomes and mobile genetic elements in polluted water

Climate warming multiplies the threat of antibiotic resistance genes (ARGs) to public health, but whether temperature may predict antibiotic resistomes in water environment remain unknown. Here, by metagenomic sequencing, we investigated the changes of resistome at five different temperature gradients (23, 26, 29, 32, and 35 degrees C) in polluted water by animal cadaver. Thirty ARG types including 668 subtypes were observed in our samples. Temperature significantly influenced ARG profiles and showed a negative correlation with ARG diversity. The ARG assembly process was dominated by a deterministic process (63.32%-95.08%) but showed a peak pattern with temperature. Notably, temperature may predict approximately 21% of ARGs and 36% of mobile genetic elements (MGEs), while most other ARGs or MGEs were insensitive to temperature. Three types (carbapenem, dicyclomycin, and diaminopyrimidine antibiotic) and 63 subtypes of ARGs that positively correlated with temperature were identified in the polluted water. Notably, we screened 21 subtypes of high-risk ARGs (bacA, mdtA, tetM, etc.) and 22 opportunistic pathogens (Aeromonas, Clostridium, Bacteroides, etc.) and found their positive co-occurrence with temperature, implying these potential biological or genetic pollutants may probably go up under global warming. Our study reveals the predictability of temperature on antibiotic resistance genes, providing a suitable approach to track the fate and spread of ARGs in water environment under climate warming.

Automated summary

Climate warming enhances the threat of antibiotic resistance genes (ARGs) to public health, and this study investigates the relationship between temperature and resistome in a water environment. The results show that temperature significantly influences ARG profiles and diversity, with certain ARGs and mobile genetic elements (MGEs) being sensitive to temperature. High-risk ARGs and opportunistic pathogens are positively correlated with temperature, indicating a potential increase in these biological or genetic pollutants under global warming. This study reveals the predictability of temperature on antibiotic resistance genes and provides a suitable approach to track their fate and spread in water environment under climate warming.