Enzymology and ecology of the nitrogen cycle.
The nitrogen cycle describes the processes through which nitrogen is converted between its various chemical forms. These transformations involve both biological and abiotic redox processes. The principal processes involved in the nitrogen cycle are nitrogen fixation, nitrification, nitrate assimilation, respiratory reduction of nitrate to ammonia, anaerobic ammonia oxidation (anammox) and denitrification. All of these are carried out by micro-organisms, including bacteria, archaea and some specialized fungi. In the present article, we provide a brief introduction to both the biochemical and ecological aspects of these processes and consider how human activity over the last 100 years has changed the historic balance of the global nitrogen cycle.
Department of Agricultural Chemistry and Biochemistry, Science Faculty Phase II, University of Alicante, 03690 San Vicente del Raspeig, Alicante, Spain. rosa.martinez@ua.es
Rosa María
RM
Martínez-Espinosa
Jeffrey A
JA
Cole
David J
DJ
Richardson
Nicholas J
NJ
Watmough
D000818:Animals; D058440:Denitrification; D004463:Ecology; D005308:Fertilizers / Q000009:adverse effects; D006801:Humans; D009569:Nitric Oxide / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism*; D009585:Nitrogen Dioxide / Q000378:metabolism
D005308:Fertilizers; D009569:Nitric Oxide; D009584:Nitrogen; D009585:Nitrogen Dioxide