Novel glycogen-accumulating organism relevant to EBPR

TY - CONF

T1 - Novel glycogen-accumulating organism relevant to EBPR

AU - Meyer, Rikke Louise

AU - Saunders, Aaron Marc

AU - Blackall, Linda Louise

PY - 2005

Y1 - 2005

N2 -  Deterioration of enhanced biological phosphorus removal (EBPR) has been linked to the proliferation of glycogen-accumulating organisms (GAOs) in both lab-scale reactors and full-scale wastewater treatment plants. Only few GAOs have been identified to date, and the phylogenetic diversity amongst bacteria possessing the metabolic phenotype of GAOs is not well characterized. This study used rRNA-based stable isotope probing to identify GAOs in a lab-scale sequencing batch reactor showing the GAO phenotype. The biomass was exposed to 13C-propionate only under anaerobic conditions during the anaerobic-aerobic reactor cycle, and this lead to labeling of a group of Alphaproteobacteria that were closely related to the isolate Defluvicoccus vanus. Two FISH probes were designed for this group and post FISH chemical staining of intracellular polyhydroxyalkanoates (PHA) showed that PHA was produced under anaerobic conditions and consumed under aerobic conditions, as per the GAO phenotype. The organisms constituted 33% of all Bacteria in the reactor from which they were identified, but they also appeared to be abundant (51 and 55% of Bacteria) in two other lab-scale EBPR reactors where the EBPR process had deteriorated. The organisms were found to be present in sludges from two full-scale treatment plants performing EBPR, and absent in sludges from two non-EBPR plants.

AB -  Deterioration of enhanced biological phosphorus removal (EBPR) has been linked to the proliferation of glycogen-accumulating organisms (GAOs) in both lab-scale reactors and full-scale wastewater treatment plants. Only few GAOs have been identified to date, and the phylogenetic diversity amongst bacteria possessing the metabolic phenotype of GAOs is not well characterized. This study used rRNA-based stable isotope probing to identify GAOs in a lab-scale sequencing batch reactor showing the GAO phenotype. The biomass was exposed to 13C-propionate only under anaerobic conditions during the anaerobic-aerobic reactor cycle, and this lead to labeling of a group of Alphaproteobacteria that were closely related to the isolate Defluvicoccus vanus. Two FISH probes were designed for this group and post FISH chemical staining of intracellular polyhydroxyalkanoates (PHA) showed that PHA was produced under anaerobic conditions and consumed under aerobic conditions, as per the GAO phenotype. The organisms constituted 33% of all Bacteria in the reactor from which they were identified, but they also appeared to be abundant (51 and 55% of Bacteria) in two other lab-scale EBPR reactors where the EBPR process had deteriorated. The organisms were found to be present in sludges from two full-scale treatment plants performing EBPR, and absent in sludges from two non-EBPR plants.

M3 - Paper

T2 - Activated Sludge Population Dynamics

Y2 - 17 December 2010

ER -