Biological nitrite oxidation in the presence of MnO2 under anoxic conditions

In this study, we demonstrate that nitrite can be biologically oxidized to nitrate under anoxic conditions, with MnO2 serving as the electron acceptor. Using an up-flow reactor, we enriched an anoxic microbial community in which nitrite oxidation occurred consistently in the absence of oxygen and was coupled with MnO2 reduction.