Evaluating responses of nitrification and denitrification to the co-selective pressure of divalent zinc and tetracycline based on resistance genes changes

• Published in: Bioresource technology Vol. 314; p. 123769
• Main Authors: Wang, Zichao, Yuan, Shengyu, Deng, Zhiwei, Wang, Yuejing, Deng, Shilong, Song, Youtao, Sun, Congting, Bu, Naishun, Wang, Xinruo
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.10.2020
• Subjects: Co-selective pressure; Divalent zinc; Hosts; Resistance genes; Tetracycline; Hosts; Divalent zinc; Resistance genes; Co-selective pressure; Tetracycline
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2020.123769

[Display omitted] •Mixed Zn(II)/TC had antagonistic effects on the AMO, NOR, NAR and NIR activities.•Mixed Zn(II)/TC induced the increase of ARGs levels and the decrease of HMRGs levels.•Mixed Zn(II)/TC enhanced bacterial TC enzymatic modification resistance.•Mixed Zn(II)/TC enhanced bacterial outer membrane resistance to Zn(II).•Potential hosts of ARGs and/or HMRGs were investigated by network analysis. The responses of nitrification and denitrification to the divalent zinc (Zn(II)) and tetracycline (TC) co-selective pressure were evaluated in a sequencing batch reactor (SBR). The removal rates of organics and nitrogen, nitrifying and denitrifying enzymatic activity, and microbial diversity and richness at the Zn(II) and TC co-selective pressure were higher than those at the alone Zn(II) selective pressure, while were lower than those at the individual TC selective pressure. The Zn(II) and TC co-selective pressure induced the TC resistance genes abundance increase and the Zn(II) resistance genes levels decrease, and enhanced bacterial enzymatic modification resistance to TC and bacterial outer membrane resistance to Zn(II). The network analysis showed that the genera Nitrospira and Nitrosomonas of nitrifiers and the genera Ferruginibacter, Dechloromonas, Acidovorax, Rhodobacter, Thauera, Cloacibacterium, Zoogloea and Flavobacterium of denitrifiers were the potential hosts of antibiotics resistance genes (ARGs) and/or heavy metals resistance genes (HMRGs).