Antibiotic Resistance Gene Was Increased via Horizontal Transfer in Single and Two-Chamber Microbial Electrolysis Cells

Abstract

\n Microbial electrolysis cells (MECs), have been applied for antibiotic degradation, but simultaneously induced antibiotic resistance genes (ARGs), thus representing a risk to disseminate antibiotic resistance. However, there were few studies on the potential and risk of ARGs transmission in the MECs. In this work, conjugative transfer of ARGs was assessed under three tested conditions (voltages, cell concentration, and donor/recipient ratio) in both single and two-chamber MECs. The results indicated that voltages (>\u20090.9 V) facilitate the frequency in single-chamber the MECs and two-chamber the MECs (in anode chamber). The donor cell number (donor/recipient ratio was 2:1) showed more favor on the transfer frequency. Furthermore, voltages ranged from 0.9 V to 2.5 V increased ROS production and cell membrane permeability in MECs. These findings offer new insights into the roles of ARGs transfer under different applied voltages in the MECs, which should not be ignored for horizontal transfer of antibiotic resistance.