摘要 

   本研究将包括 3 株芽孢杆菌和 1 株酵母菌在内的复合微生物菌剂接种到猪粪堆肥中，以探讨对抗生素抗性基因（ARGs）和移动遗传元件（MGEs）、微生物群落结构和病原菌的影响。结果表明，检测到的 ARGs 的丰度范围为 3.6 × 103 至 1.13 × 108 拷贝/g。丰度最高的 ARGs 是 sul2，最低的是 blaCTX。堆肥将大部分 ARG 和 MGE 去除了 22.8-99.7%。这些 ARG 在堆肥的嗜热阶段显着减少。堆肥堆不同层的ARGs去除率不同为：中层>上层>下层。但一些 ARGs 在堆肥成熟阶段显着增殖，尤其是磺胺抗性基因。复合微生物菌剂提高堆肥温度，加速水分流失和固氮，使堆肥中β-内酰胺酶抗性基因、转座子基因tn916和部分四环素抗性基因的去除率提高3.7-23.8%。复合微生物菌剂改变了群落结构，增加了堆肥嗜热期芽孢杆菌的丰度。并且有助于在堆肥过程中去除病原体。复合菌剂的加入导致厚壁菌门减少，拟杆菌门增加，这可能与ARGs的去除和增殖有关。

   In this study, compound microbial inoculants, including three Bacillus strains and one Yeast strain, were inoculated into swine manure composting to explore the effects on antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs), microbial community structure, and pathogenic bacteria. The results indicated that the abundances of the detected ARGs ranged from 3.6 × 103 to 1.13 × 108 copies/g. The ARGs with the highest abundance was sul2, and the lowest was blaCTX. Composting removes most of the ARGs and MGEs by 22.8–99.7%. These ARGs were significantly reduced during the thermophilic phase of compost. The removal rate of ARGs at the different layers of compost pile was different as follows: middle layer > upper layer > lower layer. But some ARGs proliferated significantly in the maturation phase of compost, especially the sulfonamide resistance genes. Compound microbial inoculants increased the temperature of compost, accelerated water loss, nitrogen fixation, and increased the removal rate of β-lactamase resistance genes, the transposon gene tn916 and part of tetracycline resistance genes by 3.7–23.8% in compost. Compound microbial inoculants changed the community structure and increased the Bacillus abundance in the thermophilic phase of compost. And it was helpful for removing pathogens during composting. The addition of compound microbial inoculants causes the decrease of Firmicutes and the increase of Bacteroidetes, which may be related to the removal and proliferation of ARGs.

  https://www.frontiersin.org/articles/10.3389/fmicb.2020.592592/full