The occurrence and role of Nitrospira in nitrogen removal systems

• Published in: Bioresource technology Vol. 303; p. 122936
• Main Authors: Mehrani, Mohamad-Javad, Sobotka, Dominika, Kowal, Przemyslaw, Ciesielski, Sławomir, Makinia, Jacek
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.05.2020
• Subjects: Ammonia; Bacteria; Comammox; Denitrification; dissolved oxygen; Meta-analysis; Nitrification; Nitrite-oxidizing bacteria; Nitrites; Nitrogen; nitrogen content; Nitrogen removal; nitrogen-fixing bacteria; Nitrospira; oxidation; Oxidation-Reduction; temperature; Nitrogen removal; Nitrite-oxidizing bacteria; Comammox; Nitrospira; Meta-analysis
• ISSN: 0960-8524; 1873-2976; 1873-2976
• DOI: 10.1016/j.biortech.2020.122936

[Display omitted] •Research on Nitrospira in wastewater systems has sharply increased in last decade.•DO and influent NH4-N have the most effect on enhancing/suppressing Nitrospira.•Influent NH4-N and pH have the highest and lowest effect on changing Nitrospira.•Temperature effect on Nitrospira activity is described by modified Ratkowsky eq. Application of the modern microbial techniques changed the paradigm about the microorganisms performing nitrification. Numerous investigations recognized representatives of the genus Nitrospira as a key and predominant nitrite-oxidizing bacteria in biological nutrient removal systems, especially under low dissolved oxygen and substrate conditions. The recent discovery of Nitrospira capable of performing complete ammonia oxidation (comammox) raised a fundamental question about the actual role of Nitrospira in both nitrification steps. This review summarizes the current knowledge about morphological, physiological and genetic characteristics of the canonical and comammox Nitrospira. Potential implications of comammox for the functional aspects of nitrogen removal have been highlighted. The complex meta-analysis of literature data was applied to identify specific individual variables and their combined interactions on the Nitrospira abundance. In addition to dissolved oxygen and influent nitrogen concentrations, temperature and pH may play an important role in enhancing or suppressing the Nitrospira activity.