User talk:Zachary.kummet

Campylobacter concisus Introduction: Campylobacter concisus is a gram negative bacterium that has a spiral appearance to it; in fact the word campylobacter actually means twisted bacteria. C. Concisus also has a single polar flagellum to use for mobility. It usually contains a deoxyribonucleic acid guanine and cytosine content of about 34-38%. C. Concisus has a very active motility and also tends to grow better at temperatures near 45 degrees Celsius compared to temperatures near 25 degrees Celsius where they grow very poorly if at all. This bacterium is a heterogeneous species complex that is made up of several different genetically distinct taxa. To separate these different taxa PCR analysis can be done on the 23 rRNA gene. Also cluster analysis of amplified fragment length polymorphism or random amplified polymorphic DNA can be performed.

Description: Campylobacter concisus was first found and named by Tanner et al (1981) when they were doing studies on people with periodontal disease and also gingivitis. More recently it has been discovered in people with Crohn’s disease and ulcerative colitis. One interesting issue about C. concisus is that it does not always cause harm to the host person when this bacteria is found in the gastrointestinal tract. Multiple studies have been performed on patience with and without Crohn’s disease and patience without the disease have been discovered to host a form of this bacterium. One of the proposed explanations for this happening is the presence of several genes located on exotoxin 9. These genes that were present were strains that had little or no invasion potential. Another possible explanation for the reason for why C. concisus was found in both people with Crohn’s disease and those without was the DNA-cytosine methyltransferase which is located between the site specific recombinase and the restriction endonuclease. These were only found in the strains with low invasive potential but were not found in the ones that were noninvasive, which makes it a less likely cause. A third possible explanation is that the flagellum might have an effect on the pathogenicity. Although it isn’t proven there is reason to believe that when these bacteria are able to be close to each other within the body they are able to auto-agglutinate. By doing auto-agglutinating the cells are able to form micro-colonies, and thus have a higher motility which gives them a better chance of getting through the intestinal mucus layer to reach the epithelial surface. After reaching the epithelial surface if the bacteria contain the proper pathogenicity factors, like exotoxin 9, they can enter into the host cell, create an inflammatory response, and cause disease.

Treatment: Rifaximin is an antibiotic that has been shown to be effective for the treatment of Campylobacter species. In different studies and tests it has been suggested that it can be effective on patients with Crohn’s disease although a very large dose may be needed. Also a short term course of rifaximin followed by a long-term course of probiotics also has shown to remiss Crohn’s disease.

References

Deshpande N P, Kaakoush N D, Wilkins M R, and Mitchell H M. 2013. Comparative genomics of Campylobacter concisus isolates reveals genetic diversity and provides insights into disease association. BMC Genomics, 14:585

Lavrencic P, Kaakoush N O, Huinao K D, Kain N, and Mitchell H M. 2012 Investigation of motility and biofilm formation by intestinal Campylobacter concisus strains. Gut Pathogens 4:22

Kaakoush N O and Mitchell H M. 2012. Campylobacter concisus – A New Player in Intestinal Disease. Front Cell Infect Microbiology. 2: 4.

Kalischuk L D and Inglis G D. 2011. Comparative genotypic and pathogenic examination of Campylobacter concisus isolates from diarrheic and non-diarrheic humans. BMC Microbiology. 11:53.

Zhang L, Budiman V,. Day A S, Mitchell H,. Lemberg D A, Riordan S M, Grimm M, Leach S T and Ismail Y. 2010. Isolation and Detection of Campylobacter concisus from Saliva of Healthy Individuals and Patients with Inflammatory Bowel Disease. Journal of Clinical Microbiology. August; 48(8): 2965–2967

Guslandi M. 2009. Campylobacter concisus: a New Character in the Crohn's Disease Story?. Journal of Clinical Microbiology. May; 47(5): 1614–1615.