摘要
      厌氧消化（AD）被广泛用于处理含有多种污染物（抗性基因（ARGs）、金属/杀生物剂抗性基因（MBRGs）、整合子整合酶基因、人类病原体和病原体毒力因子（VFs））的畜禽粪便。然而，这些污染物的相互作用以及基质复杂性对AD中污染物的影响是难以捉摸的。本研究通过16S rRNA和16S rNA基因的元转录组测序和扩增子测序，研究了猪粪AD期间这些污染物和细菌群落的动态。不同AD过程的污染物分布和细菌群落不同，但多种药物、四环素、氨基糖苷类和利福霉素的ARGs、多种杀生物剂、多种金属、铜和砷的MBRGs、整合素整合酶基因intI1、大肠杆菌、解没食子链球菌和产气荚膜梭状芽孢杆菌的潜在病原体始终占主导地位，VFs参与病原体粘附，以及厚壁菌门、拟杆菌门和变形菌门的细菌门。基质复杂性的降低（用简单基质、苹果渣或果糖代替部分猪粪，这是一种复杂的基质）降低了ARGs和MBRGs的流行率和随机周转率。网络分析显示，在基质复杂性降低的情况下，污染物之间的相互作用减少。我们的研究结果提供了对AD期间各种污染物动力学的机械理解，并揭示了基质复杂性在控制污染物流行和相互作用方面的重要性。
Abstract
Anaerobic digestion (AD) is widely used to treat livestock manure that harbors diverse pollutants (resistance genes (ARGs), metal/biocide resistance genes (MBRGs), integron-integrase genes, human pathogens and pathogen virulence factors (VFs)). However, the interplays of these pollutants and the effects of substrate complexity on pollutants in AD are elusive. This study investigated the dynamics of these pollutants and bacterial communities during AD of swine manure, by metatranscriptomic sequencing and amplicon sequencing of 16 S rRNA and 16 S rRNA gene. The pollutant profiles and bacterial communities differed across AD processes, nevertheless with consistent dominance of ARGs of multi-drugs, tetracycline, aminoglycoside and rifamycin, MBRGs of multi-biocides, multi-metals, copper and arsenic, the integron-integrase gene intI1, potential pathogens of Escherichia coli, Streptococcus gallolyticus and Clostridium perfringens, VFs involved in pathogen adherence, and bacterial phyla of Firmicutes, Bacteroidetes and Proteobacteria. Reduced substrate complexity (replacing a part of swine manure, a complex substrate, with a simple substrate, apple waste or fructose) decreased the prevalence and stochastic turnover of ARGs and MBRGs. Network analyses revealed decreased interplays among pollutants under reduced substrate complexity. Our findings provide a mechanical understanding of diverse pollutants dynamics during AD, and reveal the importance of substrate complexity in controlling prevalence and interplays of pollutants.

https://www.sciencedirect.com/science/article/abs/pii/S0304389422012341