Sustained nitrogen loss in a symbiotic association of Comammox Nitrospira and Anammox bacteria

WATER RESEARCH

卷:202

Article

Gottshall, Ekaterina Y.¹  Bryson, Sam J.¹  Cogert, Kathryn I.¹  Landreau, Matthieu¹  Sedlacek, Christopher J.²  Stahl, David A.¹  Daims, Holger^2,3  Winkler, Mari¹ 

[1] Univ Washington, Civil & Environm Engn, 476 Benjamin Hall, Seattle, WA 98165 USA

[2] Univ Vienna, Ctr Microbiol & Environm Syst Sci, A-1010 Vienna, Austria

[3] Univ Vienna, Comammox Res Platform, A-1010 Vienna, Austria

关键词: Comammox;    Anammox;    Nitrification;    Nitrogen cycle;   

DOI  :  10.1016/j.watres.2021.117426

来源: Elsevier

【 摘 要 】

The discovery of anaerobic ammonia-oxidizing bacteria (Anammox) and, more recently, aerobic bacteria common in many natural and engineered systems that oxidize ammonia completely to nitrate (Comammox) have significantly altered our understanding of the global nitrogen cycle. A high affinity for ammonia (K-m(app),K-NH3 approximate to 63nM) and oxygen place Comammox Nitrospira inopinata, the first described isolate, in the same trophic category as organisms such as some ammonia-oxidizing archaea. However, N. inopinata has a relatively low affinity for nitrite (K-m,K-NO2 approximate to 449.2 mu M) suggesting it would be less competitive for nitrite than other nitrite-consuming aerobes and anaerobes. We examined the ecological relevance of the disparate substrate affinities by coupling it with the Anammox bacterium Candidatus Brocadia anammoxidans. Synthetic communities of the two were established in hydrogel granules in which Comammox grew in the aerobic outer layer to provide Anammox with nitrite in the inner anoxic core to form dinitrogen gas. This spatial organization was confirmed with FISH imaging, supporting a mutualistic or commensal relationship. The functional significance of interspecies spatial organization was informed by the hydrogel encapsulation format, broadening our limited understanding of the interplay between these two species. The resulting low nitrate formation and the competitiveness of Comammox over other aerobic ammonia- and nitrite-oxidizers sets this ecological cooperation apart and points to potential biotechnological applications. Since nitrate is an undesirable product of wastewater treatment effluents, the Comammox-Anammox symbiosis may be of economic and ecological importance to reduce nitrogen contamination of receiving waters.

【 授权许可】

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