Authors: Meng Li JiDong Gu
Publish Date: 2013/03/03
Volume: 97, Issue: 22, Pages: 9859-9874
Abstract
The anthropogenic nitrogen N input as an important source strongly influences the microbial N cycling in coastal ecosystems In this study we investigated the responses of anammox bacteria ammonia oxidizing archaea AOA and ammonia oxidizing bacteria AOB to the amendments of ammonium and nitrite into mangrove sediments incubated in laboratory microcosm experiments The variations of diversity abundances and transcription of 16S rRNA and hydrazine oxidoreductase hzo genes for anammox bacteria and amoA genes for AOA and AOB were monitored during the incubation The TRFLP analysis demonstrated that both ammonium and nitrite additions significantly altered the community compositions of anammox bacteria AOA and AOB while abundance and transcripts analyzed quantitatively confirmed that the amendment of ammonium 25 mM stimulated the growth of anammox bacteria AOA and AOB whereas nitrite 08 mM generally inhibited them with some exceptions for specific species of AOA and AOB showing different responses of anammox bacteria AOA and AOB to the nitrite and ammonium amendments Results further suggest that AOB as the dominant group with higher amoA gene abundances and transcripts might play a more important role on the ammonium oxidization in mangrove sediment of this subtropical siteThis research was partly supported by a PhD studentship ML and Environmental and Conservation Fund grant No 15/2011 JDG We thank Ms Jessie Lai and Ms Ping Han for general laboratory support and Mr Yongfeng Wang for assistance in field sampling
Keywords: