Helicobacter pylori

Species of bacteria

Helicobacter pylori, previously known as Campylobacter pylori, is a gram-negative bacterium best known for its role in infecting the human stomach, often causing gastric ulcers and sometimes stomach cancer. Its helical body (from which the genus name Helicobacter derives) is thought to have evolved to penetrate the mucous lining of the stomach, helped by its flagella, and thereby establish infection. Mutants can have a rod or curved rod shape that exhibits less virulence.

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