[Comparative Analysis of the Bacterial Community on Anodic Biofilms in Sediment Microbial Fuel Cell Under Open and...

To investigate the differences in microbial community of anodic biofilms under open and closed circuits, sediment microbial fuel cell (SMFCs) reactors connecting with a 5 kΩ external resistance and open circuit during the start-up period were operated individually. Anodic biofilms were collected and analyzed using Solexa high-throughput sequencing technology. A total of 3936 and 3930 operational taxonomic units (OTUs) were obtained from the anodic biofilms under open and closed circuits, respectively. After 97% similarity merging, 1581 and 1551 OTUs were finally determined from open and close circuit biofilms, respectively. The analysis of α diversity showed that bacterial diversity of anodic biofilm under open circuit was higher than that under closed circuit. The dominant bacterial were Proteobacteria, Firmicutes and Bacteroidetes for both open and closed circuits. They accounted for 59.79%, 12.54% and 9.02% under open circuit biofilm respectively; and these values were 63.02%, 10.01% and 3.60% in the closed circuit biofilm respectively, and Geobacter accounted for 16.55% in the closed circuit biofilm. The present study demonstrated that the electron transfer process during start-up period affected the microbial community structure of the anodic biofilms.