title: Impacts of addition of natural zeolite or a nitrification inhibitor on antibiotic resistance genes during sludge composting.
abstract: Composting is commonly used for the treatment and resource utilization of sewage sludge, and natural zeolite and nitrification inhibitors can be used for nitrogen conservation during sludge composting, while their impacts on ARGs control are still unclear. Therefore, three lab-scale composting reactors, A (the control), B (natural zeolite addition) and C (nitrification inhibitor addition of 3,4-dimethylpyrazole phosphate, DMPP), were established. The impacts of natural zeolite and DMPP on the levels of ARGs were investigated, as were the roles that heavy metals, mobile genetic elements (MGEs) and the bacterial community play in ARGs evolution. The results showed that total ARGs copies were enriched 2.04 and 1.95 times in reactors A and C, respectively, but were reduced by 1.5% in reactor B due to the reduction of conjugation and co-selection of heavy metals caused by natural zeolite. Although some ARGs (blaCTX-M, blaTEM, ermB, ereA and tetW) were reduced by 0.3-2 logs, others (ermF, sulI, sulII, tetG, tetX, mefA and aac(6')-Ib-cr) increased by 0.3-1.3 logs after sludge composting. Although the contributors for the ARGs profiles in different stages were quite different, the results of a partial redundancy analysis, Mantel test and Procrustes analysis showed that the bacterial community was the main contributor to the changes in ARGs compared to MGEs and heavy metals. Network analysis determined the potential host bacteria for various ARGs and further confirmed our results.
authors.affiliation: State Key Joint Laboratory of Environmental Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: zjyzjjzmt@gmail.com.
authors.forename: Junya
authors.initials: J
authors.lastname: Zhang
authors.affiliation: State Key Joint Laboratory of Environmental Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: mxchen@rcees.ac.cn.
authors.forename: Meixue
authors.initials: M
authors.lastname: Chen
authors.affiliation: State Key Joint Laboratory of Environmental Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Qianwen
authors.initials: Q
authors.lastname: Sui
authors.affiliation: State Key Joint Laboratory of Environmental Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Tong
authors.affiliation: State Key Joint Laboratory of Environmental Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Jiang
authors.affiliation: School of Chemical and Environmental Engineering, China University of Mining and Technology, Beijing 100083, China.
authors.forename: Xueting
authors.initials: X
authors.lastname: Lu
authors.affiliation: School of Chemical and Environmental Engineering, China University of Mining and Technology, Beijing 100083, China.
authors.forename: Yuxiu
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: State Key Joint Laboratory of Environmental Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: yswei@rcees.ac.cn.
authors.forename: Yuansong
authors.initials: Y
authors.lastname: Wei
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D004352:Drug Resistance, Microbial; D005798:Genes, Bacterial / Q000187:drug effects*; D058465:Nitrification / Q000187:drug effects*; D012722:Sewage / Q000382:microbiology; D014865:Waste Disposal, Fluid; D017641:Zeolites / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D012722:Sewage; D017641:Zeolites
keywords: 3,4-Dimethylpyrazole phosphate (DMPP); Antibiotic resistance genes; Bacterial community; Natural zeolite; Sludge composting