Molecular detection of anammox bacteria in terrestrial ecosystems: Distribution and diversity

Abstract

Anaerobic oxidation of ammonium (anammox) is recognized as an important process in the marine nitrogen cycle yet nothing is known about the distribution, diversity and activity of anammox bacteria in the terrestrial realm. In this study, we report on the detection of anammox sequences of Candidatus Brocadia, Kuenenia, Scalindua and Jettenia in marshes, lakeshores, a contaminated porous aquifer, permafrost soil, agricultural soil and in samples associated with nitrophilic or nitrogen-fixing plants. This suggests a higher diversity of anammox bacteria in terrestrial than in marine ecosystems and could be a consequence of the larger variety of suitable niches in soils. Anammox bacteria were not ubiquitously present but were only detected in certain soil types and at particular depths, thus reflecting specific ecological requirements. As opposed to marine water column habitats where Candidatus Scalindua dominates anammox guilds, Kuenenia and Brocadia appear to be the most common representatives in terrestrial environments. © 2010 International Society for Microbial Ecology All rights reserved.