Microecology of aerobic denitrification system construction driven by cyclic stress of sulfamethoxazole

Xiao-Yan Fan; Zhong-Xing Zhang; Xing Li; Yuan-Kun Liu; Shen-Bin Cao; Wen-Nian Geng; Ya-Bao Wang; Xiao-Han Zhang

doi:10.1016/j.biortech.2024.130801

Microecology of aerobic denitrification system construction driven by cyclic stress of sulfamethoxazole

Bioresour Technol. 2024 May 6:402:130801. doi: 10.1016/j.biortech.2024.130801. Online ahead of print.

Authors

Xiao-Yan Fan¹, Zhong-Xing Zhang², Xing Li³, Yuan-Kun Liu³, Shen-Bin Cao³, Wen-Nian Geng³, Ya-Bao Wang³, Xiao-Han Zhang³

Affiliations

¹ Faculty of Architecture, Civil and Transportation Engineering, Beijing University of Technology, Beijing 100124, PR China. Electronic address: fanxy@bjut.edu.cn.
² Faculty of Architecture, Civil and Transportation Engineering, Beijing University of Technology, Beijing 100124, PR China; Center for Situation Analysis and Planning and Assessment, Chinese Academy for Environmental Planning, Beijing 100041, PR China.
³ Faculty of Architecture, Civil and Transportation Engineering, Beijing University of Technology, Beijing 100124, PR China.

PMID: 38710419
DOI: 10.1016/j.biortech.2024.130801

Abstract

The construction of aerobic denitrification (AD) systems in an antibiotic-stressed environment is a serious challenge. This study investigated strategy of cyclic stress with concentration gradient (5-30 mg/L) of sulfamethoxazole (SMX) in a sequencing batch reactor (SBR), to achieve operation of AD. Total nitrogen removal efficiency of system increased from about 10 % to 95 %. Original response of abundant-rare genera to antibiotics was changed by SMX stress, particularly conditionally rare or abundant taxa (CRAT). AD process depends on synergistic effect of heterotrophic nitrifying aerobic denitrification bacteria (Paracoccus, Thauera, Hypomicrobium, etc). AmoABC, napA, and nirK were functionally co-expressed with multiple antibiotic resistance genes (ARGs) (acrR, ereAB, and mdtO), facilitating AD process. ARGs and TCA cycling synergistically enhance the antioxidant and electron transport capacities of AD process. Antibiotic efflux pump mechanism played an important role in operation of AD. The study provides strong support for regulating activated sludge to achieve in situ AD function.

Keywords: Aerobic denitrification; Antibiotic resistance genes; Cyclic stress; Microecology; Sulfamethoxazole.

Publication types

Review