Nitrite Oxidation in Wastewater Treatment: Microbial Adaptation and Suppression Challenges
Zicheng Su1, Tao Liu1, Jianhua Guo1
1Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St. Lucia, Queensland 4072, Australia.
Environmental Science & Technology
|August 17, 2023
Summary
Nitrite-oxidizing bacteria (NOB) are key to nitrate generation in wastewater treatment. Understanding their diverse traits is crucial for developing effective strategies to manage NOB in biological nitrogen removal processes.
Area of Science:
- Environmental microbiology
- Wastewater treatment
- Nitrogen cycling
Background:
- Microbial nitrite oxidation by nitrite-oxidizing bacteria (NOB) is essential for nitrate production in wastewater treatment.
- Despite extensive study, NOB are often problematic in advanced biological nitrogen removal, with suppression strategies frequently failing due to adaptive NOB growth.
- Understanding NOB diversity is critical for optimizing wastewater treatment processes.
Purpose of the Study:
- To review the historical understanding of nitrite-oxidizing bacteria (NOB) genera.
- To construct a phylogenetic tree illustrating NOB diversity across different phyla.
- To summarize the growth behavior and metabolic performance of various NOB strains.
Main Methods:
- Literature review of NOB genera and their history.
- Phylogenetic analysis to visualize NOB diversity.
- Compilation and summary of NOB growth and metabolic data.
Main Results:
- A wide range of NOB across different phyla were identified and phylogenetically organized.
- Specific NOB strains exhibit distinct physiological traits, such as high oxygen affinity (Nitrospira), inhibitor tolerance (Nitrobacter, Candidatus Nitrotoga), and thermophily (Nitrolancea).
- These differentiated traits suggest specialized ecological niches and potential for adaptation to various suppression strategies.
Conclusions:
- The physiological characteristics and genomic information of NOB are key to their adaptation and emergence in wastewater treatment.
- Understanding NOB ecophysiology is vital for designing effective and robust NOB suppression strategies.
- Future wastewater treatment research must integrate physiological and genomic insights for improved nitrogen removal.
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