The bio-denitrification was usually retarded by the unbalance of electron generation and consumption. In this study, mixing S. oneidensis MR-1 with denitrifying microbial community increased the nitrogen removal rate by 74.74 % via the interspecies electron transfer (IET), and reduced the accumulated nitrite from 9.90 ± 0.81 to 0.02 ± 0.03 mg/L. Enhanced denitrification still appeared but relatively decreased, when S. oneidensis MR-1 was separated by a dialysis bag (MW < 3000), indicating mediated interspecies electron transfer (MIET) counted in IET. The results of electron transfer activity and sludge conductivity suggested DIET and MIET jointly transfer electrons from MR-1 to electroactive denitrifying bacteria (EDB), improving denitrifying reductase activities. Electron distribution among denitrifying reductases was found to be associated with the IET rate. Microbial insights showed the total abundance of EDB was increased, and denitrifying genes were correspondingly enriched. Pseudomonas was found to cooperate with exoelectrogens in a complicated microbial community.

电子产生和消耗的不平衡通常会阻碍生物反硝化作用。在这项研究中，将 S. oneidensis MR-1 与反硝化微生物群落混合，通过种间电子转移 (IET) 将氮去除率提高了 74.74%，并将积累的亚硝酸盐从 9.90 ± 0.81 减少到 0.02 ± 0.03 mg/L。当 S. oneidensisMR-1 被透析袋 (MW < 3000) 分离，表明介导的种间电子转移 (MIET) 在 IET 中计数。电子转移活性和污泥电导率的结果表明 DIET 和 MIET 共同将电子从 MR-1 转移到电活性反硝化细菌 (EDB)，提高反硝化还原酶活性。发现反硝化还原酶之间的电子分布与 IET 率相关。微生物观察显示 EDB 的总丰度增加，反硝化基因也相应丰富。发现假单胞菌与复杂微生物群落中的产电原合作。