Thiomargarita namibiensis

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Description and significance

Thiomargarita Namibiensis also referred to as the “Sulfur pearl of Namibia,” is the largest bacterium known to mankind thus far. Thiomargarita Namibiensis is referred to as the sulfur pearl of Namibia because it looks like a large pearl made out of white globules of sulfur and was found off the coast of Namibia. Shortly after its discovery in 1999 Thiomargarita Namibiensis was said to be generally 0.1 - 0.3 mm wide with exception of a few which reach up to a size of 1.0 mm. Thiomargarita Namibiensis is said to be 3 million times the volume of a normal bacterium cell.

Genome structure

Once discovered scientist were able to place Thiomargarita Namibiensis in to the phylogenetic tree were they concluded that Thiomargarita Namibiensis is closing related to the bacterial genera Triploca and Beggiatoa because of the high sulfur enivorment it is able to survive in. Thiomargarita Namibiensis is from the family of bacteria known as Thiotrichaceae.

Cell structure and metabolism

Thiomargarita Namibiensis is a chemolithotroph, which means that it obtains its electrons required for the electron transport chain from nitrates rather then organic molecules. The sulfur granules found in the cytoplasm of this organism is due to the oxidation of Hydrogen Sulfide in to sulfur. Thiomargarita Namibiensis is a non-motile organism, due to this it must wait for its nitrate supply and store it for long periods of time. The cytoplasm of Thiomargarita Namibiensis lines the cell membrane, giving the bacterium the flexibility to diffuse the nitrate from its surroundings.Thiomargarita Namibiensis contains a large vacuole which is 80% of its size in its cytoplasm for the shortage of nitrates and can survive three months at a time if nitrate supply is low in its environment.

Ecology

Thiomargarita namibiensis is found in the sulfur-rich sediments of the ocean floor, where they play an important ecological role. By oxidizing sulfur they act as detoxifiers, removing the poisonous gas from the water and keeping it hospitable for the fish and other marine organisms. Locations such as the one where Thiomargarita namibiensis was first uncovered are rich in phytoplankton. When this phytoplankton sinks to the bottom, the organic material is oxidized by anaerobic bacteria on the seafloor. The oxidation yields a large amount of sulfide, which Thiomargarita namibiensis is able to oxidize through a number of morphological adaptations. Like the coast of Namibia, the west coast of South America is also abundant with phytoplankton, providing an ideal habitat for Thiomargarita namibiensis. [[Image:Tnamibiensis.jpg|thumb|300px|right| Photo comparing a cell of Thiomargarita namibiensis to the eye and head of a fruit fly. The bacterium's size in proportion to other bacteria is described by scientists to be that of a blue whale to a newborn mouse.

Thiomargarita Namibiensis is found in sulfur-rich sediments in the ocean off the shore of Namibia. These bacteria play a essential role in there enivornment by oxidizing sulfur, and removing toxic gases from the water allowing it to be suitable for other marine organisms.Thiomargarita Namibiensis also perfers to be in an anaerobic enivornment, resulting its habitant being close to phytoplankton.

Pathology

As of current day research Thiomargarita Namibiensis is not known to be a pathogenic bacterium.

Application to Biotechnology

Thiomargarita Namibiensis is not currently being ultized in biotechnology. Thiomargarita Namibiensis can contribute greatly to biotechnology by becoming a tool in releasing stored phosphorus in sediments, and also in releasing sulfur from landfill gases.

Current Research

Heide N. Schulz and Horst D. Schulz Large Sulfur Bacteria and the Formation of Phosphorite

This paper reports on the biotechnical use of Thiomarigarita Namibiensis. The paper entails the ability of Thiomarigarita Namibiensis in releasing phosphorus in to its surrounding environment. Phosphorus is an essential nutrient which remains deposited in the marine sediments. The presence of Thiomarigarita Namibiensis in the marine waters of Namibian may account for abundance of apatite in that environment. Later studies showed that under laboratory experimentation in anoxic conditions, Thiomarigarita Namibiensis released large amounts of phosphate which can be correlated to the large amount of hydroxyapatite observed by the researchers in the sediments on the Namibian marine shelf.

References

1. http://www.sciencemag.org/cgi/content/abstract/307/5708/416

2. http://www.accessexcellence.org/WN/SUA12/marg499.php

3. http://web.mst.edu/~microbio/BIO221_2005/T_namibiensis.htm

4. http://www.scienceagogo.com/news/19990318191806data_trunc_sys.shtml

5. http://www.whoi.edu/oceanus/viewImage.do?id=5667&aid=2497

6. http://www.madsci.org/posts/archives/2006-06/1151465295.Mi.r.html

7. http://en.wikipedia.org/wiki/Thiomargarita_namibiensis

8. http://microbewiki.kenyon.edu/index.php/Thiomargarita