摘要

       尸体在水中分解会造成严重的环境污染，对水质和公众健康构成极大威胁。然而，对胴体分解过程中的水微生物群落演替和抗生素抗性基因（ARG）的探索较少。使用高通量测序和高通量定量 PCR 技术，在含有两种不同类型的水（黄河水和自来水）的实验组（鱼尸体）和对照组（无尸体）中水细菌群落和 ARGs 谱的时间序列水）在不同演替阶段进行了研究。我们的研究结果表明，尸体群体中的 NH3-N 浓度大幅上升，平均超过水质安全阈值的 28 倍以上。一些潜在的病原菌毛毛单胞菌属、拟杆菌属和假单胞菌属在胴体分解过程中显着增加。实验组中黄河水和自来水的细菌群落表现出相似的演替模式，并且随着时间的推移，两组之间的群落差异逐渐减小，表明细菌群落趋同。 NH3-N、NO3-N和时间是决定细菌群落结构的三个最重要的因素。水体类型对尸体细菌群落结构的影响显着但较弱。实验组中7个检测到的ARG（cmlA1-01、floR、sul1、sul2、tetG-01、tetM-01和tetQ）的基因拷贝数比对照组更丰富。与对照组黄河水基因tetQ相比，尸体组中ARGs浓度甚至增加了19倍（最低）至148倍（最高）。冗余分析 (RDA) 表明拟杆菌和厚壁菌门与所有检测到的 ARG 显着相关。本研究强调尸体降解导致氮污染恶化，潜在病原体丰度增加，以及ARGs从动物尸体转移到水环境中，从而揭示相关水污染对人类健康的有害影响。

       Carcass decomposition in water may cause serious environmental pollution, which poses a great threat to water quality and public health. However, water microbial community succession and antibiotic resistance genes (ARGs) during carcass decomposition process are less explored. Using high-throughput sequencing and high-throughput quantitative PCR techniques, the temporal succession of water bacterial communities and ARGs profiles in experimental groups (fish carcasses) and control groups (no carcasses) containing two different types of water (the Yellow River water and tap water) in different successional stages were studied. Our results showed that NH3-N concentration in the corpse groups has greatly risen and exceeded more than 28 times on average over the safety thresholds of water quality. Some potential pathogenic genera Comamonas, Bacteroides and Pseudomonas significantly increased during carcass decomposition process. The bacterial communities of the Yellow River water and tap water in the experimental groups exhibited similar succession patterns, and community dissimilarities between the two groups decreased and smaller over time, indicating that bacterial community convergence. NH3-N, NO3-N and time were three most important factors in determining bacteria community structures. The influence of water type on corpse bacterial community structures was significant but weak. The gene copy number of seven detected ARGs (cmlA1-01, floR, sul1, sul2, tetG-01, tetM-01 and tetQ) in the experimental groups was more abundant than that in the control groups. The ARGs concentrations in the corpse groups were even enriched 19-fold (minimum) to 148-fold (maximum) compared to the gene tetQ of the Yellow River water in the control groups on the initial stage. Redundancy analysis (RDA) indicated that Bacteroidetes and Firmicutes were significantly correlated with all detected ARGs. This study emphasizes that cadaver degradation leads to the deterioration of nitrogen pollution, the abundance increase of potential pathogens, and the transfer of ARGs from dead animals to water environment, thereby uncovering the harmful effects of related water pollution for human health.

https://www.sciencedirect.com/science/article/abs/pii/S0304389420317842