User:KeinsleyM: Difference between revisions
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==Pathology== | ==Pathology== | ||
By residing in untreated water and animals frequently consumed by humans, C. jejuni infects humans by infecting their gastrointestinal tract. Eating raw or uncooked poultry and beef can cause these infections along with consumption of untreated water and unpasteurized milk. To cause infection, as few as 400 bacterial cells must be consumed, although this number may vary on the susceptibility of the human. (6) | |||
The bacterium’s ability to infect is determined by the motility, chemotaxis and the flagella that are used to attach to the intestinal epithelial cells. Other virulence determinants are host cell invasion, toxin production, epithelial disruption, and inflammation. Recent studies have shown it to be antimicrobial-resistant causing treatment to become more difficult. (7) | |||
C. jejuni is a leading cause of gastroenteritis in the United States and underdeveloped countries. It causes mild to sever diarrhea, vomiting, nausea, headaches, and muscle weakness. The symptoms can last days or even weeks depending on the status of the immune system of the infected person and the amount of cells ingested. More serious cases have caused meningitis, pneumonia, and resulted in some miscarriages. (6) | |||
==Current Research and or Application to Biotechnology== | ==Current Research and or Application to Biotechnology== | ||
Revision as of 03:47, 10 May 2012
A Microbial Biorealm page on the genus KeinsleyM
Classification
Higher order taxa
Domain: Bacteria; Phylum: Proteobacteria; Class: Epsilon Protobacteria; Order: Camplyobacterales; Family: Campylobacteraceae [Others may be used. Use NCBI link to find]
Species
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NCBI: [1] |
Genus: Campylobacter; Species: C. jejuni
Description and significance
Campylobacter jejuni is a gram-negative bacterium that can be isolated from cattle, chickens, birds, flies and non-chlorinated water. This rod shaped bacterium is generally isolated from the feces of the animals listed earlier and the most pathogenic form is transmitted from chickens. (2)
This motile bacterium is a major cause of gastroenteritis, causing diarrhea, nausea, headaches, and other muscle pains. The bacterium is usually ingested after eating raw or undercooked chicken. (2)
Genome structure
C. jejuni are slender rods with a circular chromosome containing 1,641,481 base pairs encoding 1,654 proteins and 54 RNA species. 30.6% of the base pairs are G+C. In order to survive, C. jejuni has hypervariable sequences found in genes encoding synthesis or modification of surface structures. It is believed that in order for Campylobacter jejuni to survive, it must have these hypervariable sequences in the genome as they have a high rate of variation. This genome does not contain any insertion sequences, phage-associated sequences, or repeat sequences. (3)
Cell structure and metabolism
Campylobacter jejuni are gram-negative, rod shaped, motile bacteria. They contain a flagellum at one end of their spiral structure. They have corkscrew motility and joing to form zigzag patterns. (6) C. jejuni test positive for nitrate reduction, oxidase, catalase, and MacConkey’s agar. It is also able to grow at high temperatures and low temperatures. Room temperature conditions do not promote growth. With minimal oxygen and a moist habitat, they can survive nearly a month. It uses carbohydrates found inside the gastrointestinal tract to gain energy for growth. (4)
Ecology
C. jejuni is most often found infecting cattle, chickens, birds and flies. It has been found in non-chlorinated water as well. Generally, isolation of this bacterium is done using the feces of these animals. This bacterium is highly infective, explaining why so many livestock types are infected. By residing in untreated water sources, it easily infects livestock. It does not generally contribute to its environment in water or animals, but causes disease in humans. (6)
Pathology
By residing in untreated water and animals frequently consumed by humans, C. jejuni infects humans by infecting their gastrointestinal tract. Eating raw or uncooked poultry and beef can cause these infections along with consumption of untreated water and unpasteurized milk. To cause infection, as few as 400 bacterial cells must be consumed, although this number may vary on the susceptibility of the human. (6)
The bacterium’s ability to infect is determined by the motility, chemotaxis and the flagella that are used to attach to the intestinal epithelial cells. Other virulence determinants are host cell invasion, toxin production, epithelial disruption, and inflammation. Recent studies have shown it to be antimicrobial-resistant causing treatment to become more difficult. (7)
C. jejuni is a leading cause of gastroenteritis in the United States and underdeveloped countries. It causes mild to sever diarrhea, vomiting, nausea, headaches, and muscle weakness. The symptoms can last days or even weeks depending on the status of the immune system of the infected person and the amount of cells ingested. More serious cases have caused meningitis, pneumonia, and resulted in some miscarriages. (6)
Current Research and or Application to Biotechnology
Enter summaries of the most recent research and/or application to biotechnology here--at least three required
References
Edited by student of Dr. Lynn M Bedard, DePauw University http://www.depauw.edu
