April 18, 2022

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Emma O'Leary Coauthored an Article on Bacterial Populations and Municipal Wastewater Treatment Designs in the Journal of Environmental Engineering

Emma O'Leary, (Minnesota) coauthored an article entitled "Evaluating Quantitative PCR Assays to Enumerate Several Bacterial Populations of Importance in Different Municipal Wastewater Treatment Designs" published in the October 2021 issue of the Journal of Environmental Engineering.

Emma's coauthors were Taegyu Kim, Sebastian Behrens, and Timothy LaPara, all of the University of Minnesota Twin Cities.

Emma O'Leary is a Staff Professional based in Minnesota with experience in civil and environmental engineering. She focuses on water and wastewater design, remediation and phytoremediation, and environmental microbiology.

The Journal of Environmental Engineering covers systems engineering and advanced modelling as applied to environmental systems, new and promising remediation technologies, emerging pollution problems, and associated environmental policies. It offers interdisciplinary research applied to solve real environmental problems, mechanistic aspects of fate, transport and interactions of pollutants, and developments related to surface waters, groundwaters, industrial wastewaters, drinking water, air quality, soils, and sediments. The journal also publishes case studies in environmental engineering.


This study evaluated the efficacy of quantitative polymerase chain reaction (qPCR) to monitor several pertinent bacterial populations in 25 different full-scale wastewater treatment bioreactors across 9 different system designs. All the bioreactors contained a substantial quantity of total bacterial biomass and denitrifying bacteria, independent of system design. In contrast, the quantities of ammonia oxidizing bacteria (AOB) and phosphate accumulating organisms (PAOs) measured by qPCR targeting the amoA gene and the 16S rRNA genes, respectively, from the Candidatus Accumulibacter lineage significantly correlated with system design. Bioreactors with short mean cell residence time (<2  days) had significantly lower AOB abundance than most of the other bioreactors (all pairwise comparisons P<0.0001 , except for a membrane-coupled bioreactor). Similarly, bioreactors designed for enhanced biological phosphorus removal had significantly higher relative quantities of PAOs than did conventional systems (P<10−18 ). In conclusion, these qPCR assays should be practically useful for monitoring full-scale wastewater treatment bioreactors, thereby helping to improve process performance.

More Information

About the article: Evaluating Quantitative PCR Assays to Enumerate Several Bacterial Populations of Importance in Different Municipal Wastewater Treatment Designs
About the Journal of Environmental Engineering: https://ascelibrary.org/journal/joeedu
For consultation regarding municipal wastewater treatment design, contact Emma O'Leary at This email address is being protected from spambots. You need JavaScript enabled to view it.
Learn more about Emma: Emma O'Leary – LinkedIn