Endogenous metabolism of Candidatus Accumulibacter phosphatis under various starvation conditions

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review

93 Scopus Citations
View graph of relations

Author(s)

Detail(s)

Original languageEnglish
Pages (from-to)4646-4656
Journal / PublicationWater Research
Volume41
Issue number20
Publication statusPublished - Dec 2007
Externally publishedYes

Abstract

The endogenous processes of Candidatus Accumulibacter phosphatis (referred to as Accumulibacter), a known polyphosphate-accumulating organism (PAO) responsible for enhanced biological phosphorus removal systems (EBPR), were characterized during 8-day starvation under anaerobic, anoxic, aerobic and intermittent aerobic-anaerobic conditions. A lab-scale EBPR culture with Accumulibacter representing over 85% of the entire bacterial population as quantified with fluorescence in-situ hybridization was used in the study. Cell decay rates were found to be negligible under anaerobic and anoxic conditions and may be ignored in activated sludge models. The decay rate under aerobic conditions was determined to be 0.03/d at 22 °C, considerably lower than the values commonly used in activated sludge modeling. Polyphosphate and glycogen were utilized simultaneously under anaerobic and anoxic conditions for maintenance energy production, with glycogen being the primary energy source until the glycogen content reached very low levels. Glycogen was used by Accumulibacter as the primary source of energy for maintenance under aerobic conditions in the absence of polyhydroxyalkanoates. However, Accumulibacter did not seem to use polyphosphate for energy production during aerobic starvation, clearly contrasting the anaerobic and particularly the anoxic case. Intermittent aerobic-anaerobic storage resulted in not only negligible cell decay rate, but also slower rates of glycogen and polyphosphate utilization, and may therefore be an effective strategy for long-term storage of EBPR sludge. © 2007 Elsevier Ltd. All rights reserved.

Research Area(s)

  • Candidatus Accumulibacter phosphatis, Decay, Endogenous metabolism, Enhanced biological phosphorus removal (EBPR), Maintenance, Polyphosphate-accumulating organism (PAO), Starvation, Storage polymer

Bibliographic Note

Publication details (e.g. title, author(s), publication statuses and dates) are captured on an “AS IS” and “AS AVAILABLE” basis at the time of record harvesting from the data source. Suggestions for further amendments or supplementary information can be sent to lbscholars@cityu.edu.hk.