Partial nitritation anammox reactor Raw sequence reads. wastewater metagenome

Implementation of the partial nitritation-anammox (PNA) process in wastewater treatment can support to reduce energy and cost involved in conventional wastewater treatment plant. For efficient PNA system, it is essential to understand the microbial ecology of these systems. Primarily, microbial processes invovled in PNA are associated with the ammonium oxidising bacteria (AOB) and anaerobic ammonium oxidising bacteria (AnAOB). However, biomass of PNA systems have very diverse rich community. Thus, other microorganims should be contributing to the efficiency of the PNA system. To understand the role of other microorganisms we used two lab scale single stage PNA reactors as model systems, which were operated for one year. We investigated whether (1) the microbial community and the nitrogen metabolic potential of PNA biomasses is mainly governed by AOB and AnAOB, and (2) how long-term operation influences the community and the nitrogen metabolic potential of the PNA biomasses.