Helicobacter pullorum

Classification

Higher order taxa

Domain Bacteria; Phylum Proteobacteria; Class Epsilonproteobacteria; Order Campylobacterales; Family Helicobacteraceae

Species

Genus Helicobacter; Species pullorum;

Helicobacter pullorum; H. pullorum

Description and significance

Helicobacter pullorum is a gram-negative bacteria in the genus Helicobacter. The cells are bacilli with a slight curve. They typically are 3-4 micrometers in length, and 0.3-0.5 micrometers in width. This bacteria species was discovered from chickens, specifically broiler and laying types, and has also been found in humans diagnosed with gastrointestinal disease. They live in the intestinal tract of their host species but can also infiltrate the liver, ultimately causing hepatitis. H. pullorum thrive in an environment of 37-42 degrees Celsius and are therefore classified as mesophiles, in the higher end of that temperature range. They grow in microaerobic conditions and are non-spore forming. H. pullorum can also be classified by its response to certain tests. The species is negative for indoxyl acetate esterase, urease and alkaline phophatase production. It tests positive, however, for catalase production.

H. pullorum is an avian helicobacter, and is known to infect both birds and mammals. The species is of significance as it is associated with enteritis and vibrionic hepatitis in poultry. It is also associated with gastroenteritis, diarrhea, liver, and gall bladder disease in humans, and it is speculated that it may play a role in Crohn’s disease.

The amount of infections caused by H. pullorum is most likely underestimated due to its similarities between the genera Helicobacter and Campylobacter. There is a potential for food-borne transmission of H. pullorum to humans, as it has been recognized that Campylobacter species is capable of this. A number of cases concerning the species as a major-food associated human pathogen have been reported, however, there is lack of evidence supporting the prevalence of H. pullorum in humans.

Genome structure

Helicobacter pullorum has a circular genome consisting of 1,919,070 nucleotides with a known sequence. The DNA codes for 2044 genes, 2008 of which are protein coding and 36 of which are structural RNAs. 33% of the genome consists of GC pairings.

Cell structure and metabolism

Interesting features of cell structure; how it gains energy; what important molecules it produces.

Ecology

Habitat; symbiosis; contributions to the environment.

Pathology

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

Current Research

Enter summarries of the most rescent research here--at least three required

References

Ceelen, L., Decostere, A., Verschraegen, G., Ducatelle, R., and Haesebrouck, F. "Prevalence of "Helicobacter pullorum" among Patients with Gastrointestinal Disease and Clinically Healthy Persons". "Journal of Clinical Microbiology". 2005. Volume 43. p. 2984-2986.

Schauer, D. "Enterohepatic Helicobacter Species." Helicobacter Pylori: Physiology and Genetics. Washington D.C.: ASM, 2001.

Stanley, J., Linton, D., Burnens, A., Dewhirst, F., On, S., Porter, A., Owen, R., and Costas, M. ""Helicobacter pullorum" sp.nov.-genotype and phenotype of a new species isolated from poultry and from human patients with gastroenteritis". "Microbiology". 1994. Volume 140. p. 3441-3449.

[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.