Yin Yanan, Gu Jie, Wang Xiaojuan, Song Wen, Zhang Kaiyu, Sun Wei, Zhang Xin, Zhang Yajun, Li Haichao
College of Resources and Environmental Sciences, Northwest A&F University Yangling, China.
College of Science, Northwest A&F University Yangling, China.
Front Microbiol. 2017 Mar 3;8:344. doi: 10.3389/fmicb.2017.00344. eCollection 2017.
Copper is one of the most abundant heavy metals present in swine manure. In this study, a laboratory-scale aerobic composting system was amended with Cu at three levels (0, 200, and 2000 mg kg, i.e., control, Cu200, and Cu2000 treatments, respectively) to determine its effect on the fate of copper resistance genes [copper resistance genes (CRGs): , and ], antibiotic resistance genes [antibiotic resistance genes (ARGs): (A) and (B)], and . The results showed that the absolute abundances of (A), (B), and were reduced, whereas those of and increased after swine manure composting. Redundancy analysis showed that temperature significantly affected the variations in CRGs, ARGs, and . The decreases in CRGs, ARGs, and were positively correlated with the exchangeable Cu levels. The bacterial community could be grouped according to the composting time under different treatments, where the high concentration of copper had a more persistent effect on the bacterial community. Network analysis determined that the co-occurrence of CRGs, ARGs, and , and the bacterial community were the main contributors to the changes in CRGs, ARG, and . Thus, temperature, copper, and changes in the bacterial community composition had important effects on the variations in CRGs, ARGs, and during manure composting in the presence of added copper.
铜是猪粪中含量最丰富的重金属之一。在本研究中，在实验室规模的好氧堆肥系统中添加了三个水平的铜（0、200和2000毫克/千克，即分别为对照、Cu200和Cu2000处理），以确定其对铜抗性基因[铜抗性基因（CRGs）： 、 和 ]、抗生素抗性基因[抗生素抗性基因（ARGs）： （A）和 （B）]以及 的影响。结果表明，猪粪堆肥后， （A）、 （B）和 的绝对丰度降低，而 和 的绝对丰度增加。冗余分析表明，温度显著影响CRGs、ARGs和 的变化。CRGs、ARGs和 的减少与可交换铜水平呈正相关。不同处理下，细菌群落可根据堆肥时间进行分组，其中高浓度铜对细菌群落的影响更持久。网络分析确定，CRGs、ARGs和 以及细菌群落的共现是CRGs、ARG和 变化的主要贡献因素。因此，在添加铜的情况下，温度、铜和细菌群落组成的变化对猪粪堆肥过程中CRGs、ARGs和 的变化具有重要影响。
