Nitrification and Anammox with urea as the energy source
Publication year
2004Source
Systematic and Applied Microbiology, 27, 3, (2004), pp. 271-278ISSN
Publication type
Article / Letter to editor
Display more detailsDisplay less details
Organization
Ecological Microbiology
Journal title
Systematic and Applied Microbiology
Volume
vol. 27
Issue
iss. 3
Page start
p. 271
Page end
p. 278
Subject
Ecological MicrobiologyAbstract
Urea is present in many ecosystems and can be used as an energy source by chemolithotrophic aerobic ammonia oxidizing bacteria (AOB). Thus the utilization of urea in comparison to ammonia, by AOB as well as anaerobic ammonia oxidizing (Anammox) bacteria was investigated, using enrichments cultures, inoculated with activated sludge, and molecular ecological methods. In batch enrichment cultures grown with ammonia a population established in 2 weeks, which was dominated by halophilic and halotolerant AOB as determined by fluorescence in situ hybridization (FISH) experiments, with the 16S rRNA targeting oligonucleotide probe NEU. In other batch enrichment cultures using urea, the AOB population was assessed by PCR amplification, cloning and phylogenetic analysis of amoA and ribosomal 16S rRNA genes. While only one of the 48 16S rRNA gene clones could be identified as AOB (Nitrosomonas oligotropha), the amoA approach revealed two more AOB, Nitrosomonas europaea and Nitrosomonas nitrosa to be present in the enrichment. FISH analysis of the enrichment with probe NEU and newly designed probes for a specific detection of N. oligotropba and N. nitrosa related organisms, respectively, showed that N. oligotropha-like AOB formed about 50% of the total bacterial population. Also N. nitrosa (about 15% of the total population) and N. europaea (about 5%) of the total population) were relatively abundant. Additionally, continuous enrichments were performed under oxygen limitation. When ammonia was the energy source, the community in this reactor consisted of Anammox bacteria and AOB hybridizing with probe NEU. As the substrate was changed to urea, AOB related to N. oligotropha became the dominant AOB in this oxygen limited consortium. This resulted in a direct conversion of urea to dinitrogen gas, without the addition of organic carbon.
This item appears in the following Collection(s)
- Academic publications [238441]
- Electronic publications [122518]
- Faculty of Science [34986]
- Open Access publications [97513]
Upload full text
Use your RU credentials (u/z-number and password) to log in with SURFconext to upload a file for processing by the repository team.