Phosphorus removal performance, intracellular metabolites and clade-level community structure of Tetrasphaera-dominated polyphosphate accumulating organisms at different temperatures

Abstract

Tetrasphaera are polyphosphate accumulating organisms (PAOs) that play an important role in enhanced biological phosphorus removal (EBPR) from wastewater. The effect of a wide range of temperature changes (1–30 °C) on phosphorus removal, metabolism and clade-level community structure of Tetrasphaera-dominated PAOs was investigated. At 10 °C, the bioactivities of Tetrasphaera-dominated communities were obviously inhibited and the EBPR efficiency was only 73 %. Yet at 20–30 °C, EBPR efficiency reached 99 % and the relative abundance of Tetrasphaera was up to 90 %. The temperature variation changed the community distribution of Tetrasphaera clades, which was possibly a main reason for EBPR performance. Amino acids and PHA with different contents were intracellular metabolite of Tetrasphaera-dominated communities during phosphorus release and uptake at different temperatures. Moreover, Tetrasphaera fermented protein and amino acids and released VFAs. The outcomes suggested the great potential of Tetrasphaera-PAOs in the treatment of wastewater with varying temperatures and limited carbon sources.