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　beta-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.　(C)　2016　Elsevier　B.V.　All　rights　reserved.