T. namibiensis was discovered in 1997 by researchers from the Max Planck Institute for Marine Microbiology off the coast of Namibia in southwestern Africa. The finding was significant as T. namibiensis is the biggest bacteria ever found. It is the same size as the period at the end of this sentence. It is not just slightly the biggest bacteria found, it is much bigger then the previous “largest bacteria.” If the previous largest bacteria were to be scaled up to the size of a lion, T. namibiensis would be the size of a blue whale! Possibly even more awe inspiring is the comparison of average-sized bacteria to T. namibiensis. If T. namibiensis were still the size of a blue whale, normal sized bacteria would be as small as a newborn mouse.
Heidi Schulz, one of the researchers who discovered T. namibiensis is quoted as saying that these bacteria have, “survival techniques that would be the envy of any extremophile.” This is due to their interesting way of making energy. They use sulfide to oxidize nitrate. The trouble with this process is that the bacteria are not always in contact with nitrate. To combat this problem, T. namibiensis has a very large vacuole which it uses to store nitrate. It then utilizes this nitrate when it is in areas that are not high in nitrogen concentration. Since it is free floating, it occasionally runs in to nitrogen and will take this chemical in to its vacuole and store it for later. In order to store this much nitrogen, the vacuole is 98% of the bacteria’s size. Since it needs so much sulfur in order to survive, T. namibiensis lives in areas which are rich in organic carbon and thus have a high concentration of sulfur. These areas are mainly found in the sediment of the ocean floor.
The appearance of T. namibiensis is sometimes likened to a pearl necklace. It is a shiny organism due to the reflective effect that the sulfur within each cell has. The bacteria also grow together and are attached by thin strands of mucus. So, they are both shiny and come in beaded strands as a pearl necklace does.
There are some questions that are still to be answered concerning T. namibiensis. The researchers are wondering if this organism may have a multiple set of genes. It is such a big bacteria, that if proteins were made at only one location, they would have to travel very far to some parts of the cell. Also, researchers are curious about some possible uses for T. namibiensis. Since it takes up so much nitrate for energy, it may be possible to use this bacteria to clean coastal waters that are polluted from nitrates due to agricultural runoff.
References:
http://www.sciencemag.org/cgi/reprint/307/5708/416.pdf
http://www.eurekalert.org/pub_releases/1999-04/AAft-BBEF-160499.php
*Disclaimer - This report was written by a student participaring in a microbiology course at the Missouri University of Science and Technology. The accuracy of the contents of this report is not guaranteed and it is recommended that you seek additional sources of information to verify the contents.
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