High Dissolved Oxygen Selection against Nitrospira Sublineage I in Full-Scale Activated Sludge

Research output: Contribution to journalJournal article – Annual report year: 2019Researchpeer-review


  • Author: Law, Yingyu

    Nanyang Technological University, Singapore

  • Author: Matysik, Artur

    Nanyang Technological University, Singapore

  • Author: Chen, Xueming

    PROSYS - Process and Systems Engineering Centre, Department of Chemical and Biochemical Engineering, Technical University of Denmark, Søltofts Plads, 2800, Kgs. Lyngby, Denmark

  • Author: Swa Thi, Sara

    Nanyang Technological University, Singapore

  • Author: Ngoc Nguyen, Thi Quynh

    Nanyang Technological University, Singapore

  • Author: Qiu, Guanglei

    Nanyang Technological University, Singapore

  • Author: Natarajan, Gayathri

    Nanyang Technological University, Singapore

  • Author: Williams, Rohan B H

    National University of Singapore, Singapore

  • Author: Ni, Bing-Jie

    University of Technology Sydney, Australia

  • Author: Seviour, Thomas William

    Nanyang Technological University, Singapore

  • Author: Wuertz, Stefan

    Nanyang Technological University, Singapore

View graph of relations

A single Nitrospira sublineage I OTU was found to perform nitrite oxidation in full-scale domestic wastewater treatment plants (WWTPs) in the tropics. This taxon had an apparent oxygen affinity constant lower than that of the full-scale domestic activated sludge cohabitating ammonium oxidizing bacteria (AOB) (0.09 ± 0.02 g O2 m-3 versus 0.3 ± 0.03 g O2 m-3). Thus, nitrite oxidizing bacteria (NOB) may in fact thrive under conditions of low oxygen supply. Low dissolved oxygen (DO) conditions selected for and high aeration inhibited the NOB in a long-term lab-scale reactor. The relative abundance of Nitrospira sublineage I gradually decreased with increasing DO until it was washed out. Nitritation was sustained even after the DO was lowered subsequently. The morphologies of AOB and NOB microcolonies responded to DO levels in accordance with their oxygen affinities. NOB formed densely packed spherical clusters with a low surface area-to-volume ratio compared to the Nitrosomonas-like AOB clusters, which maintained a porous and nonspherical morphology. In conclusion, the effect of oxygen on AOB/NOB population dynamics depends on which OTU predominates given that oxygen affinities are species-specific, and this should be elucidated when devising operating strategies to achieve mainstream partial nitritation.
Original languageEnglish
JournalEnvironmental Science and Technology
Issue number14
Pages (from-to)8157-8166
Publication statusPublished - 2019
CitationsWeb of Science® Times Cited: No match on DOI

ID: 183862697