Microbes play a prominent role in the global nitrogen cycle.
One link in that cycle, the reduction of atmospheric
dinitrogen (N2) to ammonia, is accomplished only by prokaryotes.
Ammonia is assimilated by cells and is incorporated into numerous
biomolecules. In addition to aliphatic amines and amino acids,
there are thousands of naturally occurring nitrogenous ring
compounds. For one class alone, the alkaloids, over 10,000
different structures have been elucidated. Nitrogenous industrial
compounds include NH3, nitrate, and nitric acid.
For more information:
Medline for nitrogen metabolism AND bacteria
Tavares CR, Rocha RR, Guedes TA. Nitrification and denitrification
processes for biologic treatment of industrial effluents.
Appl Biochem Biotechnol. 2001 Spring;91-93:437-46.
Villaverde S, Lacalle ML, Garcia-Encina PA, Fdz-Polanco
F. Nitrification-denitrification of UASB effluents highly
loaded with nitrogen in an activated sludge reactor operated
with short cycled aeration. Water Sci Technol. 2001;44(4):279-86.