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Veterinary bacteriology: information about important bacteria
Veterinary bacteriology

Species/Subspecies: Helicobacter pylori
Categories: Motile; primarily of interest in human medicin
Etymology: Genus name: a helix shaped rod.
Species epithet: of the pylorus (the lower orifice of the stomach).
Significance:  [Very important]   
Alternative Species Name(s):Campylobacter pylori
Type Strain: Royal Perth Hospital 13487 = ATCC 43504 = CCUG 15815 B, 17874 and 39500 = NCTC 11637.
Macromorphology (smell):
Micromorphology: Motile rod (0.5 x 3.0 µm), which is spiral shaped, and has 4-6 flagella.
Gram +/Gram -:G-
Metabolism: Microaerophilic
Other Enzymes: Urease +
Fermentation of carbohydrates: Helicobacter spp. can neither ferment nor oxidize carbohydrates. Exception: H. pylori, which can oxidize glucose to acetate.
Spec. Char.:
HostsDiseaseClinical picture
HumansGastritisGastritis with nausea and abdominal pain and gastric ulcers. Have also been associated with gastric cancer (adenocarcinoma)
Virulence Factors: H. pylori has cytotoxins, which are secreted by means of a type IV secretion system.
Genome Sequence:
Acc-noStrainSize (bp)Genome
NC_000921 J99 1 643 831 1c + 0 
There are about 130 sequenced strains and many of these also have one circular plasmid.

16S rRNA Seq.:
Acc-noStrainNumber of NTOperon
Z25741 NCTC 11637T 1 454 

About 35 species have been described within the genus Helcobacter, and this genus is most closely related to Campylobacter, Arcobacter and Sulfurospirillum. H. pylori is closely related to H. bizzozeroni and other species (see phylogenetic trees in Fig. 93:1 and 2).
Comment:Nobel Prize in Physiology or Medicine in 2005 to Barry J. Marshall and J. Robin Warren for their discovery of "the bacterium H. pylori and its role in gastritis and ulcer disease".
Link: The Nobel Prize in Physiology or Medicine 2005


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