bacterial community in five full-scale membrane bioreactors Metagenome

Current knowledge of the microbial communities responsible for membrane biofouling in full-scale membrane bioreactors (MBRs) treatment plants still lacks clarity. MBRs are largely applied for wastewater treatment and water reuse; however membrane fouling remains a major problem in full-scale MBRs. In this study, high-throughput pyrosequencing was used to characterize the microbial community structure of early biofilms, mature biofilms and activated sludge in five full-scale MBRs in Seattle, Washington, USA. The objective of this study was to confirm the existence of a core microbiome within the biofouling communities in full-scale MBRs. 743,970 sequences were generated from the samples and clustered into 22,877 operational taxonomic units, however, 138 OTUs, 114 OTUs and 228 OTUs were shared respectively by the five early biofilms, mature biofilms and activated sludge within the five MBRs plants. Hierarchical clustering revealed that the microbial communities from each of the five MBRs clustered together, and the planktonic (activated sludge) bacterial community in each MBR was significantly distinct from the sessile bacterial community (early and mature biofilm on the membrane). The results elucidated the microbial community structures of membrane biofouling communities in full-scale MBR treatment plants, which remain inappropriately characterized. Therefore, additional studies are required to identify the main factors shaping the membrane biofouling communities in full-scale MBRs.