Query: NC_008212:2940000 Haloquadratum walsbyi DSM 16790, complete genome
Lineage: Haloquadratum walsbyi; Haloquadratum; Halobacteriaceae; Halobacteriales; Euryarchaeota; Archaea
General Information: A uniquely square archaeon. This hyperhalophile is of specific interest because of its unique square shape and extraordinarily large size (40m x 40m). Its culture conditions were optimized in 2004.
Subject: NC_007426:2248000 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.