ENAapplication/xmlftp://ftp.sra.ebi.ac.uk/vol1/fastq/SRR195/058/SRR19577258/SRR19577258_2.fastq.gzftp://ftp.sra.ebi.ac.uk/vol1/fastq/SRR195/059/SRR19577259/SRR19577259_2.fastq.gzftp://ftp.sra.ebi.ac.uk/vol1/fastq/SRR195/060/SRR19577260/SRR19577260_1.fastq.gzftp://ftp.sra.ebi.ac.uk/vol1/fastq/SRR195/061/SRR19577261/SRR19577261_2.fastq.gzftp://ftp.sra.ebi.ac.uk/vol1/fastq/SRR195/059/SRR19577259/SRR19577259_1.fastq.gzftp://ftp.sra.ebi.ac.uk/vol1/fastq/SRR195/062/SRR19577262/SRR19577262_1.fastq.gzftp://ftp.sra.ebi.ac.uk/vol1/fastq/SRR195/058/SRR19577258/SRR19577258_1.fastq.gzftp://ftp.sra.ebi.ac.uk/vol1/fastq/SRR195/060/SRR19577260/SRR19577260_2.fastq.gzftp://ftp.sra.ebi.ac.uk/vol1/fastq/SRR195/062/SRR19577262/SRR19577262_2.fastq.gzftp://ftp.sra.ebi.ac.uk/vol1/fastq/SRR195/061/SRR19577261/SRR19577261_1.fastq.gzprimaryOK200GenomicsChongqing Universityhttps://www.ebi.ac.uk/ena/browser/view/PRJNA832684biofilm metagenomeAlthough silver nanoparticles (Ag-NPs) were found to be responsible for N2O generation, the mechanism of Ag-NPs induced N2O production has remained controversial and needs to be confirmed. In this study, chronic Ag-NPs exposure experiments were conducted in five independent sequencing batch biofilm reactors to systematically assess the effects of Ag-NPs on N2O emissions. The results indicated that a low dose of Ag-NPs (< 1 mg/L) could slightly suppress N2O generation. In contrast, a high dose (5 mg/L) of Ag-NPs would stimulate N2O emissions by 67.54%. ICP-MS and SEM-EDS together revealed that high Ag-NPs content would accumulate on the biofilm surface when exposed with 5 mg/L Ag-NPs. Microelectrode and stable isotope analyses further demonstrated that the accumulated Ag-NPs would construct the anaerobic zone in biofilm, which may be responsible for the stimulation of the nitrite reduction pathway to release N2O. A metagenomic analysis further attributed the higher N2O emissions under high dose of Ag-NPs exposure to the higher activity of ferredoxin-nitrate reductase and nitrite reductase (NO-forming) (i.e., 1.52- and 1.29-fold higher, respectively). These findings collectively suggest that chronic high dose Ag-NPs exposure could enhance the N2O emissions by forming anaerobic micro-environment in biofilm.ENAfalseThe biofilm of SSBRThe biofilm of SSBR Raw sequence reads2023-05-192023-05-02PRJNA832684718308