Vibrio vulnificus

A Microbial Biorealm page on the genus Vibrio vulnificus

Classification

Higher order taxa

Bacteria; Proteobacteria; Gammaproteobacteria; Vibrionales; Vibrionaceae; Vibrio

Species

Vibrio vulnificus

Description and significance

V. vulnificus, a gram negative, rod shaped, halophile, is a virulent bacterium associated with about 95 percent of all seafood related deaths. It is a human pathogen known to cause gastroenteritis, wound infections and primary septicemia. This organism can typically be found in estuarine and coastal waters, thriving especially in bivalve mollusks including oysters and clams, additionally, causing health risks to those who ingest raw or undercooked seafood.

V. vulnificus has three biotypes, with biotype one, identified as a new species in 1976, caused the greatest public health concern, with its involvement with human disease. Furthermore, biotype two is associated with infected eels, and biotype three is associated with wound infections of humans.

Genome structure

The genomes of two strains of V. vulnificus, YJ016 and CMCP6, have been fully sequenced, each with two, circular chromosomes.

Chromosome I of strain YJ016 has a length of 3,354,505 nucleotides, while chromosome II contains 1,857,073 nucleotides, with a size of 5,260,086 base pairs.

Chromosome I of strain CMCP6 has 3,281,945 nucleotides in length, while chromosome II has 1,844,853 nucleotides, with a size of 5,126,798 base pairs.

It is believed that Vibrios have two chromosomes as an evolutionary advantage. The larger chromosome plays a role in growth, while the smaller one is involved in adaptation and environmental change. Phenotypic variation is also present within V. vulnificus. It is observed that no two strains are genetically identical.

Cell structure and metabolism

V. vulnificus is a gram negative bacterium. It contains pili for motility, adherence to epithelial cells and is involved in biofilm formation. Some strains contain capsules which determine virulence and are also associated with biofilm formation.

This organism is also known to be “lactose-positive” with its fermentation of lactose, salicin and cellobiose. But since phenotypic variation is observed, about 15% of strains were found to be lactose negative and another 15% were found to be sucrose positive.

In addition, this bacterium is an also known halophile, and usually grows in areas with a minimum of 5% salinity.

Endotoxin, found on lipopolysaccharides, is the major cause for this organism’s virulence and is the leading factor which causes shock or death in an infected individual.

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

Does this organism produce any useful compounds or enzymes? What are they and how are they used?

Current Research

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

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.

Paranjpye, R., and Strom, M. "A Vibrio vulnificus Type IV Pilin Contributes to Biofilm Formation, Adherence to Epithelial Cells, and Virulence. Infect Immun. 2005 March; 73(3): 1411–1422.

"Vibrio". National Microbial Pathogen Data Resource Center.

Todar, Kenneth. "Vibrio vulnificus". Todar's Online Textbook of Bacteriology. 2005.

[ Thompson, F., Austin, B., and Swings, J. (Eds.). (2006). The Biology of vibrios. (pp. 349-354, 359-361). Washington, D.C.: ASM Press.]

Edited by student of Rachel Larsen and Kit Pogliano