title: Ammonia-oxidising Crenarchaeota: important players in the nitrogen cycle?
abstract: Cultivation-independent molecular surveys show that members of the kingdom Crenarchaeota within the domain Archaea represent a substantial component of microbial communities in aquatic and terrestrial environments. Recently, metagenomic studies have revealed that such Crenarchaeota contain and express genes related to those of bacterial ammonia monooxygenases. Furthermore, a marine chemolithoautotrophic strain was isolated that uses ammonia as a sole energy source. Considering the ubiquity and abundance of Crenarchaeota, these findings considerably challenge the accepted view of the microbial communities involved in global nitrogen cycling. However, the quantitative contribution of Archaea to nitrification in marine and terrestrial environments still remains to be elucidated.
authors.affiliation: School of Biological Sciences, University of Aberdeen, Cruickshank Building, St. Machar Drive, Aberdeen, UK, AB24 3UU.
authors.forename: Graeme W
authors.initials: GW
authors.lastname: Nicol
authors.forename: Christa
authors.initials: C
authors.lastname: Schleper
mesh_terms: D000641:Ammonia / Q000378:metabolism*; D019615:Crenarchaeota / Q000378:metabolism*; D009584:Nitrogen / Q000378:metabolism*; D010084:Oxidation-Reduction
chemical_list: D000641:Ammonia; D009584:Nitrogen