Query: NC_007426:205390 Natronomonas pharaonis DSM 2160, complete genome
Lineage: Natronomonas pharaonis; Natronomonas; Halobacteriaceae; Halobacteriales; Euryarchaeota; Archaea
General Information: Isolated from Lake Gabara in Egypt. Extreme haloalkaliphilic archeon. Natronomonas pharaonis is able to survive at high salt and pH conditions which results in limited nitrogen availability through ammonium. In order to compensate for this, Natronomonas pharaonis has developed three systems to promote nitrogen assimilation: direct uptake of ammonia, uptake of nitrate, and uptake of urea. Another problem with high pH environments is the use of a proton gradient for the generation of ATP, which other alkaliphiles have adapted to by substitution of sodium ions for protons. However, this organism utilizes protons for ATP generation as determined by experimental data.
Subject: NC_007406:632436 Nitrobacter winogradskyi Nb-255, complete genome
Lineage: Nitrobacter winogradskyi; Nitrobacter; Bradyrhizobiaceae; Rhizobiales; Proteobacteria; Bacteria
General Information: Nitrite-oxidizing bacterium. Members of this genus are found in marine, freshwater, and terrestrial habitats, often in association with ammonia-oxidizing bacteria. These organisms oxidize nitrate, generated by the oxidation of ammonia, to nitrate and play an important role in the global nitrogen cycle. The enzyme involved in nitrite oxidation, nitrite oxidoreductase, can also reduce nitrate to nitrite in the absence of oxygen, allowing Nitrobacter sp. to grow anaerobically. Nitrobacter winogradskyi is commonly isolated from soil, fresh and sea water, sewage, and compost. This organism can grow anaerobically using nitrate as the electron acceptor, forming nitrite, nitric oxide, and nitrous oxide.