Huang Xu, Tian Shaohua, Zheng Jialun, Xu Kaiqin, Liu Chaoxiang
Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China; Fujian Institute of Innovation, Chinese Academy of Sciences, Fuzhou, 350002, China.
Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China; Fujian Institute of Innovation, Chinese Academy of Sciences, Fuzhou, 350002, China.
Environ Pollut. 2021 May 15;277:116819. doi: 10.1016/j.envpol.2021.116819. Epub 2021 Feb 26.
This study employed high-throughput quantitative polymerase chain reaction to evaluate the effects of specific co-substrate and additive on the fitness of antibiotic resistome during swine manure composting. The results showed that corncob particle as a co-substrate significantly reduced the relative abundances of antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs) simultaneously. The diversity of ARGs was also reduced more effectively by corncob addition. Brick granule as an additive reduced the concentrations of bioavailable Cu and Zn. However, the relative abundances of ARGs and MGEs were not reduced by the addition of brick granule subsequently. Redundancy analysis indicated a negative effect of the C content and positive effects of class I integrase gene (intI) and bioavailable metals on the variation of the relative abundance of ARGs (p < 0.01). The Procrustes test showed a higher goodness-of-fit between the relative abundance of ARGs and 16S rRNA genes (r = 0.8166; p < 0.0001). Our results suggests that the effect of corncob particle on the relative abundance of ARGs was achieved by driving the changes in physicochemical properties and microbial communities. This study confirmed the hypothesis of fitness cost and demonstrated the contribution of extra C source to ARG attenuation during composting.
本研究采用高通量定量聚合酶链反应来评估特定共底物和添加剂对猪粪堆肥过程中抗生素抗性组适应性的影响。结果表明，玉米芯颗粒作为共底物可同时显著降低抗生素抗性基因（ARGs）和移动遗传元件（MGEs）的相对丰度。添加玉米芯也能更有效地降低ARGs的多样性。砖颗粒作为添加剂可降低生物可利用铜和锌的浓度。然而，随后添加砖颗粒并未降低ARGs和MGEs的相对丰度。冗余分析表明，碳含量对抗生素抗性基因相对丰度的变化有负面影响，而I类整合酶基因（intI）和生物可利用金属有正面影响（p < 0.01）。Procrustes检验表明，抗生素抗性基因的相对丰度与16S rRNA基因之间具有较高的拟合优度（r = 0.8166；p < 0.0001）。我们的结果表明，玉米芯颗粒通过驱动理化性质和微生物群落的变化，实现了对ARGs相对丰度的影响。本研究证实了适应性代价假说，并证明了额外碳源在堆肥过程中对ARGs衰减的贡献。
