Adopt A Bacterium - Salinibacter ruber

Salinibacter ruber is a orange-red bacterium that thrives best when living in water environments that are saturated with 20% to 30% of salt. It is highly pigmented due to the presence of pigments known as carotenoids.

Salinibacter ruber are rod shaped, gram negative bacteria. This means that the bacteria does not retain the crystal violet stain throughout the gram staining method during bacterial differentiation as it has a thin peptidoglycan layer and have an outer lipid membrane. This makes the Salinibacter ruber bacteria resistant to multiple drugs. It also is aerobic with flagella for motility

Salinibacter ruber _is an extremely halophilic red bacteria and was found in saltern crystallizer ponds in Alicante and Mallorca, Spain in 2002 by Anton et al.. This environment has very high salt concentrations, and _Salinibacter ruber itself cannot grow below 15% salt concentration, with an ideal concentration between 20-30%. Salinibacter ruber _survives in this harsh environment because of its adaptations in order to cope with the high salt concentrations. These adaptations are: modifying the sequences of its proteins, recruiting proteins from different sources with different functions, as well as lateral gene transfer from other halophilic organisms.
This bacteria is very interesting because of it extremophile tendencies as a bacteria, when this is common mostly in the domain Archaea. Bacteria do not, in general, play a large role in microbial communities of hypersaline brines at or approaching NaCl saturation. However, with the discovery of S. ruber, this belief was weakened. It was found that S. ruber made up from 5% to 25% of the total prokaryotic community of the Spanish saltern ponds! (2) _Salinibacter ruber is most closely related to the genus Rhodothermus which is a thermophilic, slightly halophilic bacteria. Though genetically it is considered to be closest to the Rhodothermus genus, it is most comparable to the family Halobacteriaceae, because of similarity in protein structure.

The existence of large number of a member of the Bacteroidetes _in NaCl-saturated brines in saltern crystallizer ponds was first documented in 1999 based on fluorescence in situ hybridization studies. Isolation of the organism and its description as _Salinibacter ruber _followed soon. It is a rod-shaped, red-orange pigmented, extreme halophile that grows optimally at 20–30% salt. The genus is distributed worldwide in hypersaline environments. Today, the genus Salinibacter includes three species, and a somewhat less halophilic relative, _Salisaeta longa, has also been documented. Although belonging to the Bacteria, Salinibacter shares many features with the Archaea of the family_ Halobacteriaceae that live in the same habitat. Both groups use KCl for osmotic adjustment of their cytoplasm, both mainly possess salt-requiring enzymes with a large excess of acidic amino acids, and both contain different retinal pigments: light-driven proton pumps, chloride pumps, and light sensors. _Salinibacter produces an unusual carotenoid, salinixanthin that forms a light antenna and transfers energy to the retinal group of xanthorhodopsin, a light-driven proton pump. Other unusual features of Salinibacter and Salisaeta include the presence of novel sulfonolipids (halocapnine derivatives). _Salinibacter _has become an excellent model for metagenomic, biogeographic, ecological, and evolutionary studies.

The organisms thriving under extreme conditions better than any other organism living on Earth, fascinate by their hostile growing parameters, physiological features, and their production of valuable bioactive metabolites. This is the case of microorganisms (bacteria, archaea, and fungi) that grow optimally at high salinities and are able to produce biomolecules of pharmaceutical interest for therapeutic applications. As along as the microbiota is being approached by massive sequencing, novel insights are revealing the environmental conditions on which the compounds are produced in the microbial community without more stress than sharing the same substratum with their peers, the salt. In this review are reported the molecules described and produced by halophilic microorganisms with a spectrum of action in vitro: antimicrobial and anticancer. The action mechanisms of these molecules, the urgent need to introduce alternative lead compounds and the current aspects on the exploitation and its limitations are discussed

Salinibacter ruber is type of halophilic archaeon that thrive in water that us densely saturated with salt. These include natural brines, salt lakes, the well known Dead Sea as well as the infamous Pink Lake in Austrailia. Research shows that salt had been mined from this lake right until the early 20th century.

Since its discovery in 1998, representatives of the extremely halophilic bacterium Salinibacter ruber _have been found in many hypersaline environments across the world, including coastal and solar salterns and solar lakes. Here, we review the available information about the distribution, abundance and diversity of this member of the _Bacteroidetes

After gathering samples of the lake’s water and sediments, scientists used metagenomic analysis techniques, or DNA extraction, to assess the genetic information within. This allowed them to tease out all the different species that live in the lake. Most of the ones that researchers found love salt, and that makes sense given the lake’s striking color. Dunaliella salina _algae, after all, was present. Scientists also found several species of archaea, single-celled microbes, and a type of bacteria called _Salinibacter ruber. All of those things are colored red and help to shade Lake Hillier’s waters pink

Saturated thalassic brines are among the most physically demanding habitats on Earth: few microbes survive in them. Salinibacter ruber is among these organisms and has been found repeatedly in significant numbers in climax saltern crystallizer communities. The phenotype of this bacterium is remarkably similar to that of the hyperhalophilic Archaea (Haloarchaea). The genome sequence suggests that this resemblance has arisen through convergence at the physiological level (different genes producing similar overall phenotype) and the molecular level (independent mutations yielding similar sequences or structures). Several genes and gene clusters also derive by lateral transfer from (or may have been laterally transferred to) haloarchaea. S. ruber encodes four rhodopsins. One resembles bacterial proteorhodopsins and three are of the haloarchaeal type, previously uncharacterized in a bacterial genome. The impact of these modular adaptive elements on the cell biology and ecology of S. ruber is substantial, affecting salt adaptation, bioenergetics, and photobiology.