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

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 degrees C) on phosphorus removal, metabolism and clade-level community structure of Tetrasphaera-dominated PAOs was investigated. At 10 degrees C, the bioactivities of Tetrasphaera-dominated communities were obviously inhibited and the EBPR efficiency was only 73 %. Yet at 20-30 degrees 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.

Automated summary

This study investigated the impact of temperature changes on Tetrasphaera-PAOs and found that at lower temperatures their bioactivity was inhibited, while at higher temperatures the efficiency was very high. Temperature variation can affect the distribution of Tetrasphaera clades, which may be a main reason for EBPR performance.