Chroococcidiopsis

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Classification

Bacteria; Cyanobacteria; Cyanophyceae; Chroococcales; Xenococcaceae NCBI link to find]

Species

NCBI: Taxonomy

Genus species

Description and Significance

Chroococcidiopsis is a primitive, unicellular cyanobacteria. It can survive in diverse array of extreme conditions. They can survive under extreme temperatures or pHs, high levels of radiation, high concentrations of salt, and arid environments. It is an important microorganism to study due to their survival in this diverse array of environments. They also are can contribute to toxins as well as a desiccation tolerance.

Genome Structure

Chroococcidiopsis thermalis genome contains 6.69 megabase pairs (Mbp) made up of 6,033 genes as well as containing 5,752 encoding proteins. The genome has a G+C makeup of 44.4%.

Describe the size and content of the genome. How many chromosomes? Circular or linear? Other interesting features? What is known about its sequence?

Cell Structure, Metabolism and Life Cycle

Chroococcidiopsis is a negative gram, spherical cyanobacteria. It is prokaryotic meaning it lacks a nucleus. Chroococcidiopsis performs oxygenic photosynthesis. It is nitrogen fixing producing ammonia, nitrites, or nitrates. Heterocysts are commonly formed in low concentrations of nitrogen. Chroococcidiopsis differs from other cyanobacteria by forming tetrameric or dimeric Photosystem I reactions centers rather than the usual trimmeric complexes most cyanobacteria have. The average cell has a average diameter of 2-6 μm and is surround by thin, colorless, extracellular polysaccharide sheathes.They have a high desiccation tolerance due to the EPS that surround them.Thylakoid distributions are irregular throughout the cell. They are rarely found solitary, usually living in less spherical colonies. Cells are sometimes gathered in free-living agglomerations.

Ecology and Pathogenesis

Due to its primitive nature, it is thought that Chroococcidiopsis was a major contributor to transforming our atmosphere into to an oxidizing one by releasing its byproduct oxygen into the atmosphere. Chroococcidiopsis can produce neurotoxic by products, such as β-N-methylamino-L-alanine that can create a health hazard for drinking water, particularly in underdeveloped countries. This can lead to malfunctioning of the nervous systems, and in severe cases death. Chroococcidiopsis’ ability to live in such extreme environments is being researched and thought to be able to survive and produce organic material needed to make soil on Mars therefore allowing life on the planet. Some scientists are researching the potential farming of Chroococcidiopsis on Mars could make farmable land in the future.

References

[Sample reference] Takai, K., Sugai, A., Itoh, T., and Horikoshi, K. "Palaeococcus ferrophilus gen. nov., sp. nov., a barophilic, hyperthermophilic archaeon from a deep-sea hydrothermal vent chimney". International Journal of Systematic and Evolutionary Microbiology. 2000. Volume 50. p. 489-500.

[1] Meng, L., Semchonok, D., Boekema. ““Characterization and Evolution of Tetrameric Photosystem I from the Thermophilic Cyanobacterium Chroococcidiopsis sp TS-821”. “The Plant Cell”. March 2014.]

[2] Billi, D., Friedmann, E., Helm, R., Potts, M. “”Gene Transfer to the Desiccation-Tolerant Cyanobacterium Chroococcidiopsis”. “Journal of Bacteriology”. 2001. Volume 183. p. 2298-2305.]

[3] NASA. “Greening of the Red Planet”. “National Aeronautics and Space Administration.” January 2001.]

[4] Geitler, L. “Chroococcopsis.”]

Author

Page authored by Lauren Pifer, student of Prof. Jay Lennon at IndianaUniversity.