Helicobacter

 

Helicobacter

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Helicobacter
Scanning electron micrograph of Helicobacter bacteria.
Scientific classification
Kingdom: Bacteria Phylum: Proteobacteria Class: Epsilon Proteobacteria Order: Campylobacterales Family: Helicobacteraceae Genus: Helicobacter Goodwin et al. 1989
Species

 

Helicobacter is a genus of Gram-negative bacteria possessing a characteristic helix shape.

They were initially considered to be members of the Campylobacter genus, but since 1989 they have been grouped in their own genus.^[1][2][3]

Some species have been found living in the lining of the upper gastrointestinal tract, as well as the liver of mammals and some birds.^[4].

The most widely known species of the genus is H. pylori which infects up to 50% of the human population.^[3] Some strains of this bacterium are pathogenic to humans as it is strongly associated with peptic ulcers, chronic gastritis, duodenitis, and stomach cancer. It also serves as the type species of the genus.

Helicobacter spp. are able to thrive in the very acidic mammalian stomach by producing large quantities of the enzyme urease, which locally raises the pH from ~2 to a more biocompatible range of 6 to 7.^[5] Bacteria belonging to this genus are usually susceptible to antibiotics such as penicillin, are microaerophilic (require small amounts of oxygen), and are fast-moving with their flagella.^[6][7]

 

 

helix

1563, from L. helix "spiral," from Gk. helix (gen. helikos), related to eilein "to turn, twist, roll,"