摘要

       畜禽粪便被认为是将抗生素抗性基因 (ARG) 传播到环境中的重要来源，因此对公众健康构成直接威胁。尽管已广泛研究了重复利用粪便对土壤微生物群落和 ARGs 的影响，但对不同管理方法产生的粪便微生物群落和 ARGs 的综合特征尚不清楚。在这里，我们分析了通过三种常规管理策略处理的牛粪的微生物群落和 ARGs 的命运：好氧堆肥、机械干燥和沉淀，应用结合宏基因组学和宏蛋白质组学的集成组学方法。综合组学表明，与其他两种策略处理的粪便相比，堆肥粪便中微生物群落和 ARG 的多样性最低。定量 PCR 方法显示，无论季节如何，堆肥 14 天后 ARG 的丰度都降低了 83% 以上。此外，在堆肥后，主导机械干燥过程的潜在 ARG 宿主不动杆菌和假单胞菌的丰度急剧下降。堆肥样品中细菌、ARG 和转座酶基因 tnpA-01 之间的重要共生网络表明这些细菌在 ARG 传播中的重要作用。这些发现提供了对控制牲畜粪便再利用过程中 ARG 传播的潜在策略的见解。

       Livestock manure is considered as an important source for spreading antibiotic resistance genes (ARGs) into the environment, and therefore poses a direct threat to public health. Whereas the effects of reused manure on soil microbial communities and ARGs have been studied extensively, comprehensive characterizations of microbial communities and ARGs of manure produced by different management methods are not well understood. Here, we analyzed the fate of microbial communities and ARGs of cow manure treated by three conventional management strategies: aerobic composting, mechanical drying and precipitation, applying an integrated-omics approach combining metagenomics and metaproteomics. Integrated-omics demonstrated that composted manure contained the lowest diversity of microbial community and ARGs compared with manure treated by other two strategies. Quantitative PCR methods revealed that the abundances of ARGs were reduced by over 83 % after composting for 14 days, regardless of the season. Besides, the potential ARG hosts Acinetobacter and Pseudomonas dominating mechanical drying process were sharply decreased in abundances after composting. The significant co-occurrence networks among bacteria, ARGs and transposase gene tnpA-01 in composting samples indicated the important role of these bacteria in the dissemination of ARGs. These findings offer insight into potential strategies to control the spread of ARGs during livestock manure reuse.

https://www.sciencedirect.com/science/article/abs/pii/S0304389419318497