Functional Microbial Community in a Membrane-Aerated Biofilm Reactor Operated for Completely Autotrophic Nitrogen Removal
膜曝气生物膜反应器运行单级自养脱氮工艺功能型菌群特性研究

The 16S rDNA-based molecular technique was applied to investigate the functional microbial community of a membrane-aerated biofilm bioreactor(MABR) that was used for completely autotrophic nitrogen removal over nitrite (CANON). The relationships among two kinds of key bacteria responsible for CANON: aerobic ammonia-oxidizing bacteria (AOB) and ANAMMOX bacteria, and their possible distributions in the MAB were discussed based on the microbial community analysis. FISH analysis showed the existence of two visible active layers in experimental MAB. One was the partial nitrifying layer located in the region of oxygen-rich membrane-biofilm interface, dominated by NSO190-positive AOB. The other was the ANAMMOX active layer located in the region of anoxic liquid-biofilm interface, dominated by PLA46 and AMX820-positive ANAMMOX microorganisms. As a result, the AOB as well as ANAMMOX bacteria were present and active in experimental MABR, and the cooperation between AOB and ANAMMOX bacteria was considered to be responsible for CANON.