A　newly　designed　pilot-scale　system　was　developed　to　enrich　denitrifying　phosphate-accumulating　organisms　(DNPAOs)　for　nitrogen　and　phosphorus　nutrient　removal　synchronously.　A　strain　of　DNPAOs　was　isolated　and　its　biochemical　characteristics　and　metabolic　mechanisms　of　this　bacterial　strain　were　analyzed.　The　results　showed　that　compared　with　previously　reported　system,　this　newly　designed　system　has　higher　removal　rates　of　nutrients.　Removal　efficiencies　of　NH3-N,　TN,　TP,　and　COD　in　actual　wastewater　were　82.64%,　79.62%,　87.22%,　and　90.41%,　respectively.　Metabolic　activity　of　DNPAOs　after　anoxic　stage　in　this　study　even　reached　94.64%.　Pseudomonas　aeruginosa　is　a　strain　of　non-fermentative　DNPAOs　with　strong　nitrogen　and　phosphorus　removal　abilities.　Study　on　the　metabolic　mechanisms　suggested　that　intracellular　PHB　of　P.　aeruginosa　plays　dual　roles,　supplying　energy　for　phosphorus　accumulation　and　serving　as　a　major　carbon　source　for　denitrification.　(C)　2016　Elsevier　Ltd.　All　rights　reserved.