摘要

    动物粪便作为抗生素的主要储存库，对抗生素抗性基因（ARG）的环境压力增加有很大贡献。这可能是第一个探索不同通风方式对ARGs控制的影响并确定乳肥料堆肥过程中古菌群落与ARGs之间关系的研究。通过实时定量PCR对数种ARG进行定量，并在真空堆肥（VTC）和正压堆肥（PPC）期间通过高通量测序对包括细菌和古细菌在内的微生物群落进行了分析。在堆肥的每个阶段，在VTC下检测到的ARGs和I类整合酶基因（intI1）的总含量显着低于在PPC下（P <0.001）。根据测序信息和相关分析确定的潜在人类致病菌（HPB）的相对丰度在PPC和VTC结束时分别下降了74.6％和91.4％。古细菌群落的组成表明，在整个堆肥过程中，包括甲烷甲烷短杆菌，甲烷菌和甲烷菌在内的产甲烷古细菌占主导地位。冗余分析表明，甲烷短杆菌属和甲烷体与所有检测到的ARGs正相关。网络分析确定在VTC和PPC下ARG的可能宿主是不同的，并为古细菌和ARG之间的潜在联系提供了新的视角。我们的结果显示VTC在减少ARG和潜在HPB方面表现更好，并表明某些古细菌也可能是ARG的重要宿主，并警告了古细菌携带ARG的风险。

    As a major reservoir of antibiotics, animal manure contributes a lot to the augmented environmental pressure of antibiotic resistance genes (ARGs). This might be the first study to explore the effects of different ventilation types on the control of ARGs and to identify the relationships between archaeal communities and ARGs during the composting of dairy manure. Several ARGs were quantified via Real-time qPCR and microbial communities including bacteria and archaea were analyzed by High-throughput sequencing during vacuum-type composting (VTC) and positive-pressure composting (PPC). The total detected ARGs and class I integrase gene (intI1) under VTC were significantly lower than that under PPC during each stage of the composting (p < 0.001). The relative abundance of potential human pathogenic bacteria (HPB) which were identified based on sequencing information and correlation analysis decreased by 74.6% and 91.4% at the end of PPC and VTC, respectively. The composition of archaeal communities indicated that methane-producing archaea including Methanobrevibacter, Methanocorpusculum and Methanosphaera were dominant throughout the composting. Redundancy analysis suggested that Methanobrevibacter and Methanocorpusculum were positively correlated with all of the detected ARGs. Network analysis determined that the possible hosts of ARGs were different under VTC and PPC, and provided new sights about potential links between archaea and ARGs. Our results showed better performance of VTC in reducing ARGs and potential HPB and demonstrated that some archaea could also be influential hosts of ARGs, and caution the risks of archaea carrying ARGs.

    https://www.sciencedirect.com/science/article/abs/pii/S1001074219312276