摘要
      动物尸体腐烂引起的抗生素耐药性污染已成为一个严重的环境问题。然而，尸体分解的主要代谢产物化合物（即腐胺和尸胺）与抗生素耐药性之间的关系尚不清楚。为了解决这个问题，在实验室模拟实验的基础上，通过高通量定量PCR和扩增子测序方法，研究了水生环境中抗生素抗性基因（ARGs）和微生物组对过量腐胺、尸胺及其混合物的反应。我们的研究结果表明，腐胺和尸胺导致水和沉积物中TC（总碳）和TN（总氮）的增加。在腐胺和尸胺的暴露下，水中可移动遗传元素（MGE）和大多数ARGs的总丰度高于沉积物。特别是，与对照组相比，腐胺和尸胺导致水和沉积物中微生物群落的α多样性显著不同。尸胺和腐胺对水中和沉积物中的微生物群落结构也有显著影响。此外，腐胺和尸胺导致沉积物中高风险ARG（如mecA）和机会性病原体（如Delftia）的不同程度增加，促进了抗生素耐药性细菌的流行。总之，我们的研究结果揭示了胴体腐烂的主要代谢产物对微生物组和耐药性的影响，为风险评估和污染管理提供了参考。
Abstract
Contamination of antibiotic resistomes due to animal carcass decay has become a serious environmental concern. However, the relationship between main metabolite compounds of corpse decomposition (i.e., putrescine and cadaverine) and antibiotic resistomes remains unclear. To tackle this issue, the response of antibiotic resistance genes (ARGs) and microbiome in aquatic environment to excess putrescine, cadaverine and a mixture of both based on laboratory simulation experiment was investigated by high-throughput quantitative PCR and amplicon sequencing methods. Our results showed putrescine and cadaverine led to the increasing of TC (total carbon) and TN (total nitrogen) both in water and sediment. Under the exposure of putrescine and cadaverine, the total abundance of mobile genetic elements (MGEs) and most ARGs in water was higher than in sediment. In particular, putrescine and cadaverine caused significantly different decreases in alpha diversity of microbial community in water and sediment compared with the control group. Microbial community structures both in water and sediment were also significantly affected by cadaverine and putrescine. Furthermore, putrescine and cadaverine led to different degrees of increases of high-risk ARGs (like mecA) and opportunistic pathogens (like Delftia) in sediment, promoting the prevalence of antibiotic resistant bacteria. In conclusion, our findings revealed the influences of main metabolites of carcass decay on microbiome and resistomes, providing references for risk assessment and pollution management.

https://www.sciencedirect.com/science/article/abs/pii/S0013935122023969