Helicobacter

Helicobacter
Scanning electron micrograph of Helicobacter bilis bacteria
Scientific classification Edit this classification
Domain: Bacteria
Phylum: Campylobacterota
Class: "Campylobacteria"
Order: Campylobacterales
Family: Helicobacteraceae
Genus: Helicobacter
Goodwin et al. 1989[1]
Type species
Helicobacter pylori
(Marshall et al. 1985) Goodwin et al. 1989
Species

See text

Synonyms
  • "Gastrospirillum" McNulty et al. 1989

Helicobacter is a genus of gram-negative bacteria possessing a characteristic helical shape. They were initially considered to be members of the genus Campylobacter, but in 1989, Goodwin et al. published sufficient reasons to justify the new genus name Helicobacter.[2] The genus Helicobacter contains about 35 species.[3][4][5]

Some species have been found living in the lining of the upper gastrointestinal tract, as well as the liver of mammals and some birds.[6] The most widely known species of the genus is H. pylori, which infects up to 50% of the human population.[5] It also serves as the type species of the genus. Some strains of this bacterium are pathogenic to humans, as they are strongly associated with peptic ulcers, chronic gastritis, duodenitis, and stomach cancer.

Helicobacter species are able to thrive in the very acidic mammalian stomach by producing large quantities of the enzyme urease, which locally raises the pH from about 2 to a more biocompatible range of 6 to 7.[7] Bacteria belonging to this genus are usually susceptible to antibiotics such as penicillin, are microaerophilic (optimal oxygen concentration between 5 and 14%) capnophiles, and are fast-moving with their flagella.[8][9]

  1. ^ Cite error: The named reference LPSN was invoked but never defined (see the help page).
  2. ^ Goodwin CS, Armstrong JA, Chilvers T, et al. (1989). "Transfer of Campylobacter pylori and Campylobacter mustelae to Helicobacter gen. nov. as Helicobacter pylori comb. nov. and Helicobacter mustelae comb. nov., respectively". Int. J. Syst. Bacteriol. 39 (4): 397–405. doi:10.1099/00207713-39-4-397.
  3. ^ Boyanova, L, ed. (2011). Helicobacter pylori. Caister Academic Press. ISBN 978-1-904455-84-4.
  4. ^ Vandamme P, Falsen E, Rossaq R, et al. (1991). "Revision of Campylobacter, Helicobacter, and Wolinella taxonomy: emendation of generic descriptions and proposal of Arcobacter gen. nov". Int. J. Syst. Bacteriol. 41 (1): 88–103. doi:10.1099/00207713-41-1-88. PMID 1704793.
  5. ^ a b Yamaoka, Y., ed. (2008). Helicobacter pylori: Molecular Genetics and Cellular Biology. Caister Academic Press. ISBN 978-1-904455-31-8. [1].
  6. ^ Ryan, KJ; Ray, CG, eds. (2004). Sherris Medical Microbiology (4th ed.). McGraw Hill. ISBN 0-8385-8529-9.
  7. ^ Dunn BE, Cohen H, Blaser MJ (1 October 1997). "Helicobacter pylori". Clin Microbiol Rev. 10 (4): 720–741. doi:10.1128/cmr.10.4.720. PMC 172942. PMID 9336670.
  8. ^ Hua JS, Zheng PY, Ho B (1999). "Species differentiation and identification in the genus of Helicobacter". World Journal of Gastroenterology. 5 (1): 7–9. doi:10.3748/wjg.v5.i1.7. PMC 4688506. PMID 11819372.
  9. ^ Rust; et al. (2008). "Helicobacter Flagella, Motility and Chemotaxis". Helicobacter pylori: Molecular Genetics and Cellular Biology (Yamaoka Y, ed.). Caister Academic Press. ISBN 978-1-904455-31-8. [2].