Arthrospira platensis: Difference between revisions

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==Description and significance==
==Description and significance==
-Does not fix nitrogen(1)
Arthrospira platensis, also known as Spirulina, is a filamentous, non-toxic species of cyanobacteria with a wide array of uses in the natural and commercial world. Primarily, it is known across the world for its potential nutritional value. It is one of the rare edible bacteria due to its low purine concentration, which allows it to pose very minimal risk of uric acid build up in the body (5). Historically, it is known to have been regularly consumed by the Aztecs and tropical climate populations (1). Because of its anti-carcinogen properties, it was also used to treat radiation sickness in people that were affected by the 1986 Chernobyl nuclear accident (2). More recently, the consumption of this species has been shown to lower blood pressure and reduce cholesterol, which are two of the most prevalent health concerns in the modern world (3). The food industry classifies Arthrospira platensis as a single-celled protein, meaning that it is an edible microbe with a high food value (5). It is rich in vitamins, minerals, beta-carotene, essential fatty acids, and antioxidants, all of which have facilitated its commercial production as a human food supplement over the course of the past decade (6). It also has very high protein content with a well-balanced composition of amino acids, making it even more desirable as a food supplement (2).
-Aztecs consumed regularly, thought to be important dietary element in tropical areas(1)
-Alkali and salt tolerance and algal mat production along periphery of lakes(1)
-Presence of hydrogenase makes it useful for clean energy production(1)
-Develops cAMP-dependent signal cascades to adapt to severe environmental conditions(1)
 
-Consumption shown to lower blood pressure and reduce cholesterol(3)
-Grown commercially as a food additive(3)
 
-Commercially produced as human food supplement for over 10 years(6)
-High quality source of protein, vitamins, minerals, essential fatty acids, and beta-carotene(6)
-Grows in carbonate-rich lakes in Torrid Zones(6)
 
-Fast growing, high protein content, rich in vitamins, non-toxic, well-balanced amino acid composition(2)
-Used before and after drug treatment in order to remove harmful agents from organism and introduce elements/compounds that strengthen the immune system – creates favorable conditions for drugs to work at optimum level of performance(2)
-Used as anti-carcinogen used to treat radiation sickness in people affected by Chernobyl accident(2)
-Maximum growth achieved in 4th or 5th day of cultivation(2)
-Conditions for optimal growth: standard mineral nutrient, 30-34 deg C, pH 8.5-11, sodium light lamp(2)
 
-Spiral-shaped, filamentous, cyanobacterium, phototrophic, produce oxygen(5)
-Grow in freshwater, alkaliphiles, saline soda lakes – high salt and pH (8-11) Example: Lake Magadi(5)
-High concentration of carotenes, protein, vitamin B12, minerals, and antioxidants (prevent cancer)(5)
-Filaments approximately 5μm, cells wider than they are long, produce hormongia – short, motile chains (3-5 cells)(5)
-Gliding motility – poorly understood, no flagella(5)
-Have carboxysomes (contain Rubisco to fix CO2), gas vesicles, and thylakoid membranes as adaptations for being phototrophic(5)
-Contain lipid bacteria to store energy-rich compounds and a thick peptidoglycan cell wall (both features of all cyanobacteria)(5)
-One of the rare edible bacteria because of its low purine concentration – normally, bacteria can not be part of diet because they have a higher nucleic acid component (high purines), which form uric acid – can’t be broken down by humans and forms conditions such as gout and kidney stones(5)
-Main diet component for flamingos – carotenes released when bacteria digested and are deposited to feathers, producing pink color(5)
-Available as a health food supplement – humans don’t turn pink because it makes up such a small portion of the diet(5)
-Na+/H+ antiporters bring protons in and push Na out to drastic changes to cell pH – resistant to high salt concentration because Na is being pushed out of cells(5)
-Food industry classifies as single-celled proteins, meaning edible microbes with high food value(5)
 
-Chlorophylls, carotenoids, and phycobiliproteins are pigments used in absorption of light(4)
-Association of carotenoids and chlorophyll prevents formation of highly reactive oxygen radicals(4)
-65-70% complete protein with all essential amino acids in perfect balance(4)


==Genome structure==
==Genome structure==

Revision as of 21:49, 17 October 2011

This student page has not been curated.

A Microbial Biorealm page on the genus Arthrospira platensis

Classification

Higher order taxa

Domain: Bacteria Phylum: Cyanobacteria Class: Cyanophyceae Order: Oscillatoriales Family: Phormidiaceae

Species

Genus: Arthrospira Species: platensis

Arthrospira (Spirulina) platensis; A. platensis

Description and significance

Arthrospira platensis, also known as Spirulina, is a filamentous, non-toxic species of cyanobacteria with a wide array of uses in the natural and commercial world. Primarily, it is known across the world for its potential nutritional value. It is one of the rare edible bacteria due to its low purine concentration, which allows it to pose very minimal risk of uric acid build up in the body (5). Historically, it is known to have been regularly consumed by the Aztecs and tropical climate populations (1). Because of its anti-carcinogen properties, it was also used to treat radiation sickness in people that were affected by the 1986 Chernobyl nuclear accident (2). More recently, the consumption of this species has been shown to lower blood pressure and reduce cholesterol, which are two of the most prevalent health concerns in the modern world (3). The food industry classifies Arthrospira platensis as a single-celled protein, meaning that it is an edible microbe with a high food value (5). It is rich in vitamins, minerals, beta-carotene, essential fatty acids, and antioxidants, all of which have facilitated its commercial production as a human food supplement over the course of the past decade (6). It also has very high protein content with a well-balanced composition of amino acids, making it even more desirable as a food supplement (2).

Genome structure

In March 2010, Arthrospira platensis became the first filamentous, non-N2-fixing cyanobacterium to have its genome sequenced and published(1). The genome consists of a single, circular chromosome and was found to be 6.8Mb in size with 44.3% G-C cotent(1). There were 6630 protein-coding genes detected, as well as 49 RNA genes, including 2 sets of rRNA genes and 40 tRNA genes(1). When looked at in its entirety, 78% of the species' genes showed similarity to genes with known function in other organisms, while 22% of the genome is made up of unknown genes(1).

Cell structure and metabolism

Interesting features of cell structure; how it gains energy; what important molecules it produces.


Ecology

Habitat; symbiosis; contributions to the environment.

Pathology

How does this organism cause disease? Human, animal, plant hosts? Virulence factors, as well as patient symptoms.

Current Research

Enter summaries of the most recent research here--at least three required

Cool Factor

Describe something you fing "cool" about this microbe.

References

1. Fujisawa, Takatomo et al. “Genomic Structure of an Economically Important Cyanobacterium, Arthrospira (Spirulina) platensis NEIS-39.” DNA Research 17 (2010): 85-103.

2. Mosulishvili, L. M., E. I. Kirkesali, A. I. Beiokobylsky, and A. I. Khizanishvili. “Experimental Substantion of the Possibility of Developing Selenium and Iodine Containing Pharmaceuticals Based on Blue-green Algae Spirulina platensis.” Journal of Pharmaceutical and Biomedical Analysis 30.1 (2002): 87-97. Web. 5 Oct. 2011.

3. National Center for Biotechnology Information. Web. 05 Oct 2011. <http://www.ncbi.nlm.nih.gov/bioproject?Db=genome&Cmd=ShowDetailView&TermToSearch=6605.>

4. Singh, Nirbhay Kumar and Dolly Wattal Dhar. “Phylogenetic Relatedness Among Spirulina and Related Cyanobacterial Genera.” World J Microbiol Biotechnol 27 (2011): 941-951.

5. Slonczewski, Joan L. and John W. Foster. Microbiology: An Evolving Science. 2nd Ed. New York: W. W. Norton & Company, Inc., 2009. 141-685.

6. Watunuki, Hironubu, Kazuki Ota, Asmi Citra Malina, A. R. Tassakka, Toshimitsu Kato, and Masahiro Sakai. “Immunostimulant Effects of Dietary Spirulina platensis on Carp, Cyprinus Carpio.” Aquaculture 258. 1-4 (2006): 157-63. Web. 5 Oct. 2011.

Edited by student of Iris Keren NEUF2011