Epulopiscium fishelsoni

A Microbial Biorealm page on the genus Epulopiscium fishelsoni

Light micrograph of a large epulo and a ciliated eukaryote (C). Copyright © 1991, American Society for Microbiology

Classification

Higher order taxa

Kingdom: Bacteria

Phylum: Firmicutes

Class: Clostridia

Order: Clostridiales

Genus: Epulopiscium

Species

NCBI: Taxonomy

Epulopiscium fishelsoni

Description and significance

Describe the appearance, habitat, etc. of the organism, and why it is important enough to have its genome sequenced. Describe how and where it was isolated. Include a picture or two (with sources) if you can find them.

Epulopiscium was first discovered in 1985 by Lev Fishelson. He found them inside the intestines of a brown surgeonfish and was initially classified as a protist because of its large size. Epulopiscium fishelsoni was later discovered by Linn Montgomery and in 1993 Norman Pace performed an rRNA analysis which confirmed that it was actually a bacteria. At the time E. fishelsoni was the largest known bacteria, ranging from a length of ~30 to >600μm and a volume of >2,000-fold [2]. E. fishelsoni is a gram-positive bacterium that has an explicit symbiotic relationship with its surgeonfish hosts.

Genome structure

Describe the size and content of the genome. How many chromosomes? Circular or linear? Other interesting features? What is known about its sequence? Does it have any plasmids? Are they important to the organism's lifestyle?

Transmission electron micrographs of compact nucleoids of E. fishelsoni. Copyright © 1998, American Society for Microbiology

Cell structure and metabolism

Describe any interesting features and/or cell structures; how it gains energy; what important molecules it produces.

Ecology

Describe any interactions with other organisms (included eukaryotes), contributions to the environment, effect on environment, etc.

Pathology

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

Application to Biotechnology

E. fishelsoni does not produce any useful compound or enzymes that can be used for biotechnology. All that is known is that this bacteria helps regulate the pH in the gut of its host. This regulation is cycled throughout the day and is controlled based on the surgeonfish's activity.

Current Research

There are currently no ongoing nor recent research being done about E. fishelsoni. After its discovery in 1985, thorough examinations of its structure and research about its reproduction process in the 90's, there is not much left that we don't know about this bacteria. There aren't any signs nor indications of future research projects for E. fishelsoni.

References

1. Clements, K. D. and Bullivant, S. "An Unusual Symbiont from the Gut of Surgeonfishes May Be the Largest Known Prokaryote". Journal of Bacteriology. Sept. 1991. Volume 173, No. 17. p. 5359-5362.

2. Bresler, V., Montgomery, W.L., Fishelson, L., and Pollak, P.E. "Gigantism in a Bacterium, Epulopiscium fishelsoni, Correlates with Complex Patterns in Arrangement, Quantity, and Segregation of DNA". J Bacteriol. 1998 November; 180(21): 5601–5611.

3. Flint, J.F., Drzymalski D., Montgomery, W.L., Southam, G., and Angert, E.R. "Nocturnal Production of Endospores in Natural Populations of Epulopiscium-Like Surgeonfish Symbionts". J Bacteriol. 2005 November; 187(21): 7460–7470.

Edited by student of Rachel Larsen