摘要
      气候变暖加剧了抗生素耐药性基因（ARGs）对公众健康的威胁，但温度是否可以预测水环境中的抗生素耐药性仍然未知。在这里，通过宏基因组测序，我们研究了动物尸体污染水中在五个不同温度梯度（23、26、29、32和35°C）下的抗性组的变化。在我们的样本中观察到30种ARG类型，包括668种亚型。温度显著影响ARG剖面，并与ARG多样性呈负相关。ARG组装过程以确定性过程为主（63.32%–95.08%），但随温度变化呈峰值模式。值得注意的是，温度可以预测大约21%的ARG和36%的可移动遗传元件（MGE），而大多数其他ARG或MGE对温度不敏感。在污染水中鉴定出三种类型（碳青霉烯、二环霉素和二氨基嘧啶抗生素）和63种与温度呈正相关的ARGs亚型。值得注意的是，我们筛选了21种高危ARGs亚型（bacA、mdtA、tetM等）和22种机会性病原体（气单胞菌、梭菌、拟杆菌等），发现它们与温度呈正相关，这意味着这些潜在的生物或遗传污染物可能会在全球变暖下增加。我们的研究揭示了温度对抗生素抗性基因的可预测性，为追踪气候变暖下ARGs在水环境中的命运和传播提供了一种合适的方法。
Abstract
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 °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.

https://www.sciencedirect.com/science/article/abs/pii/S0269749122020085