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Campylobacter



 

Campylobacter

Campylobacter bacteria are the number-one cause of food-related gastrointestinal illness in the United States. To learn more about this pathogen, ARS scientists are sequencing multiple Campylobacter genomes. This scanning electron microscope image shows the characteristic spiral, or corkscrew, shape of C. jejuni cells and related structures.
Scientific classification
Kingdom: Bacteria
Phylum: Proteobacteria
Class: Epsilon Proteobacteria
Order: Campylobacterales
Family: Campylobacteraceae
Genus: Campylobacter
Sebald and Véron 1963
Species

C. coli
C. concisus
C. curvus
C. fetus
C. gracilis
C. helveticus
C. hominis
C. hyointestinalis
C. insulaenigrae
C. jejuni
C. lanienae
C. lari
C. mucosalis
C. rectus
C. showae
C. sputorum
C. upsaliensis

The genus Campylobacter are Gram-negative, spiral, microaerophilic bacteria. Motile, with either uni- or bi-polar flagella, the organisms have a somewhat curved, rod-like appearance, and are oxidase-positive.[1] Campylobacter jejuni is now recognised as one of the main causes of bacterial foodborne disease in many developed countries.[2] At least a dozen species of Campylobacter have been implicated in human disease, with C. jejuni and C. coli the most common.[1] C. fetus is a cause of spontaneous abortions in cattle and sheep, as well as an opportunisitic pathogen in humans.[3]

Additional recommended knowledge

Contents

Genome

The genomes of several Campylobacter species have been sequenced, providing insights into their mechanisms of pathogenesis.[4]

Campylobacter species contain two flagellin genes in tandem for motility, flaA and flaB. These genes undergo intergenic recombination, further contributing to their virulence. [5] Non-motile mutants do not colonize.

Pathogenesis

Main article: Campylobacteriosis

Campylobacteriosis is an infection by campylobacter [6]. The common routes of transmission are fecal-oral, person-to-person sexual contact, ingestion of contaminated food or water. It produces an inflammatory, sometimes bloody, diarrhea, periodontitis [7] or dysentery syndrome, mostly including cramps, fever and pain. The infection is usually self-limiting and in most cases, symptomatic treatment by reposition of liquid and electrolyte replacement is enough in human infections. The use of antibiotics, on the other hand, is controversial.

Cause

This is most commonly caused by C. jejuni, a spiral and comma shaped bacterium normally found in cattle, swine, and birds, where it is non-pathogenic. But the illness can also be caused by C. coli (also found in cattle, swine, and birds) C. upsaliensis (found in cats and dogs) and C. lari (present in seabirds in particular).

One cause of the effects of campylobacteriosis is tissue injury in the gut. The sites of tissue injury include the jejunum, the ileum, and the colon. C jejuni appears to achieve this by invading and destroying epithelial cells.

Some strains of C jejuni produce a cholera-like enterotoxin, which is important in the watery diarrhea observed in infections. The organism produces diffuse, bloody, edematous, and exudative enteritis. In a small number of cases, the infection may be associated with hemolytic uremic syndrome and thrombotic thrombocytopenic purpura through a poorly understood mechanism.

References

  1. ^ a b Ryan KJ; Ray CG (editors) (2004). Sherris Medical Microbiology, 4th ed., McGraw Hill, pp. 378–80. ISBN 0838585299. 
  2. ^ Moore JE, et al. (2005). "Campylobacter". Vet Res 36 (3): 351-82. PMID 15845230.
  3. ^ Sauerwein R, Bisseling J, Horrevorts A (1993). "Septic abortion associated with Campylobacter fetus subspecies fetus infection: case report and review of the literature". Infection 21 (5): 331-3. PMID 8300253.
  4. ^ Fouts DE et al. (2005). "Major structural differences and novel potential virulence mechanisms from the genomes of multiple Campylobacter species". PLoS Biol 3 (1): e15. doi:10.1371/journal.pbio.0030015. PMID 15660156.
  5. ^ Grant C, Konkel M, Cieplak W, Tompkins L (1993). "Role of flagella in adherence, internalization, and translocation of Campylobacter jejuni in nonpolarized and polarized epithelial cell cultures". Infect Immun 61 (5): 1764-71. PMID 8478066.
  6. ^ cdc.gov
  7. ^ Humphrey, Tom et al. (2007). "Campylobacters as zoonotic pathogens: A food production perspective ". International Journal of Food Microbiology 117 (3). doi:10.1016.

See also

 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Campylobacter". A list of authors is available in Wikipedia.
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