College of Engineering and Technology, Tianjin Agricultural University, Tianjin 300384, PR China.
College of Marine and Environmental Sciences, Tianjin University of Science and Technology, Tianjin 300457, PR China.
Sci Total Environ. 2020 Nov 20;744:140920. doi: 10.1016/j.scitotenv.2020.140920. Epub 2020 Jul 17.
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.
堆体温度对好氧堆肥过程中抗生素耐药基因（ARGs）、金属耐药基因（MRGs）和移动遗传元件（MGEs）命运的影响尚未完全阐明。本研究采用三种不同最高温度控制的堆肥进行测试。共检测到 211 个 ARGs、9 个 MRGs 和 44 个 MGEs。42 天后，三种处理方式下，检测到的基因数量和总丰度均普遍下降（分别为 3.8%-50.0%和 25.4%-66.0%），除了 MRGs 的总丰度增加（增加了 82.2%-500.5%）。较高的堆体温度显著刺激了基因多样性的衰减，但对促进总丰度的下降没有显著影响。对于某些基因亚型，较高的温度显著促进了它们在成熟阶段的去除或抑制了它们的反弹。erm(F)、sul1 和 floR 是堆肥过程中 ARGs 的潜在指标。MGEs IS26、int1、intl2、IncP_oriT 和 IncQ_oriT 是 ARGs 和 MRGs 的关键枢纽。不动杆菌属、假单胞菌属、棒状杆菌属 1 和蛋白菌属是多种基因的主要潜在宿主。ARG、MRG 和 MGE 谱主要受环境因素和微生物群落的共同作用驱动。
