Crocosphaera watsonii

From MicrobeWiki, the student-edited microbiology resource

Classification

Bacteria; Cyanobacteria; Oscillatoriophycideae; Chroococcales; Aphanothecaceae; Crocosphaera

Species

Crocosphaera watsonii

https://genome.jgi.doe.gov/portal/crowa/crowa.jpg

Description and Significance

Describe the appearance, habitat, etc. of the organism, and why you think it is important.

Crocosphaera watsonii is a diazotrophic marine cyanobacteria. They are found in warm water conditions where the water temperature is above 24 degrees Celcius. These cyanobacteria can be found offshore or in the open ocean.

They are about 2.5-6 µm in diameter.

Crocosphaera watsonii are unicellular nitrogen fixers that help turn nitrogen in the atmosphere into ammonia, restoring the circulation of nitrogen in the oceans.

Genome Structure

Crocosphaera watsonii has six genomes with an average length of 5.885 Mbp. C. watsonii has many different strains that each contain a phenotypic difference. However, the majority of the DNA sequences from the strains are found to be nearly identical to one another. Through culturing and sequence conservation, studies have found that the strains have been able to maintain genetic diversity through divergence and rearrangement.

One strain of C. watsonii, WH8501, showed that the mobile genetic elements, like transposase genes, have provided ways for the bacteria to mutate through genetic insertions and deletions, and through rearrangement.

These mobile genetic materials are what separates C. Watsonii from other marine cyanobacteria such as Prochlorococcus which lacks transposase genes and normally has a higher diversity sequence than C. Watsonii.

Cell Structure, Metabolism and Life Cycle

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


Crocosphaera watsonii has a 35-hour doubling time.

In the warm parts of the Atlantic and Pacific oceans, Crocosphaera watsonii has been found to have cell densities of above 1000 cells per mililiter.

Ecology and Pathogenesis

Habitat; symbiosis; biogeochemical significance; contributions to environment.

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


Crocosphaera watsonii can be isolated into two different phenotypes that can each have their own environmental impacts and niches.

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.


Author

Page authored by Ashleigh Wright, student of Prof. Bradley Tolar at UNC Wilmington.