Microbial community distribution and dominant bacterial species analysis in the bio-electrochemical system treating low concentration cefuroxime

•The bio-electrochemical system promoted antibiotics removal by 60%.•The microbial diversity was reduced in BES.•Xanthomonadaceae became the dominant species in BES.•ARGs were decreased in BES, which was related with the decrease in microbial community.

In a previous study, the authors found that a bio-electrochemical system could increase the antibiotic removal efficiency by approximately 60%. Researchers desired to examine how the microbial community changed. Thus, Illumina high-throughput sequencing was used to explore the community structures in the bio-electrochemical system and a conventional sequencing batch biofilm reactor. Through establishing operational taxonomic units, rank-abundance distribution curves, Venn diagrams, bacterial community structures, and heatmaps, the result showed that the microbial richness and diversity were reduced in the bio-electrochemical system and that Xanthomonadaceae was dominant species. In addition, copies of three types of β-lactam antibiotic resistance genes were detected, and the bio-electrochemical system showed the smallest number. Overall, this research implied that Xanthomonadaceae plays a role in removing cefuroxime and that the bio-electrochemical system has the potential to remove organisms’ antibiotic resistance genes.