Impacts of pile temperature on antibiotic resistance, metal resistance and microbial community during swine manure composting

• Published in: The Science of the total environment Vol. 744; p. 140920
• Main Authors: Wu, Nan, Xie, Shiyu, Zeng, Ming, Xu, Xiaoyan, Li, Yan, Liu, Xinyuan, Wang, Xiaobo
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 20.11.2020
• Subjects: Antibiotic resistome; Bacterial community; Compost; Metal resistance; Mobile genetic elements; Compost; Antibiotic resistome; Metal resistance; Mobile genetic elements; Bacterial community
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2020.140920

The impact of pile temperature on the fate of antibiotic resistance genes (ARGs), metal resistance genes (MRGs) and mobile genetic elements (MGEs) during aerobic composting was not fully explored. Here, three composting piles were tested with different maximum temperature control. A total of 211 ARGs, 9 MRGs and 44 MGEs were observed. After 42 days, the numbers and the total abundances of detected genes were generally decreased (3.8%–50.0% and 25.4%–66.0%, respectively) in three treatments, except for the total abundance of MRGs (increased by 82.2%–500.5%). Higher pile temperature substantially stimulated the attenuation of gene diversity, but had no significant impact on promoting the decline in total abundances. For certain gene subtypes, higher temperature remarkably promoted their removal or suppressed their rebounding during maturation phase. The erm(F), sul1 and floR were potential indicators of ARGs during composting. The MGEs IS26, int1, intl2, IncP_oriT and IncQ_oriT acted as crucial hubs for ARGs and MRGs. Genera Acinetobacter, Pseudomonas, Corynebacterium_1 and Proteiniphilum were major potential hosts for multiple genes. The ARG, MRG and MGE profiles were mainly driven by the joint effect of environmental factors and microbial community. [Display omitted] •Higher pile temperature significantly reduced the diversity of ARGs, MRGs and MGEs.•Higher temperature suppressed the rebounding of some gene subtypes.•The erm(F), sul1 and floR were potential indicators of ARGs during composting.•MGEs intl2, IncP_oriT and IncQ_oriT acted as crucial hubs for MRGs.