Natronomonas pharaonis DSM 2160

Natronomonas pharaonis (strain DSM 2160 / ATCC 35678) is an extremely haloalkaliphilic archaeon which was isolated from salt-saturated lakes of pH 11. It grows optimally at pH 8.5 in 3.5 M NaCL. Its genome consists of a chromosome and two plasmids. Twenty percent of N.pharaonis proteins have no homologs in other species. It possesses the complete set of enzymes for the biosynthesis of amino acids and coenzymes. It is probably not able to use sugar because it lacks key enzymes of glycolytic pathways. It has transporters for diverse nitrogen souces such as ammonium, urea, nitrite/nitrate in order to cope with reduced levels of ammonium ions resulting from extreme pH conditions. The Tat pathway might be extensively used not only for coenzyme-containing redox components such as halocyanins but also for the export of non-redox proteins. Lipoproteins make up one third of the predicted secretome and seem to be translocated via the Tat pathway. It possesses proteins with high N- and C-terminal similarity to halophilic cell surface glycoproteins forming regular S-layer cell envelopes, however, instead of a typical S-layer, it could form a more complex cell envelope with various glycoprotein species. It harbors a single blue-light photoreceptor that is very similar to the blue-light photoreceptor from Halobacterium. (HAMAP: NATPD)