Helicobacter pylori is a bacteria with an impressive surivival system that lives in the stomach. Urease is very important for its survival in the stomach, as it acts as a buffer for acidic environment.
After many years of assuming that peptic ulcer disease had its origins in psychological stress, some guy actually drank a bottle of H pylori and damn near killed himself to prove that it caused ulcers. As a result of this discovery, antibiotics are now being used to treat ulcers. By the by, ulcers in the stomach can be malignant, but ulcers in the duodenum are never malignant.
To test for H pylori, a blood test is effective (antibody persists for a while for diagnosis), though a C13 breath test is less invasive.
- endotoxin (e.g., LPS) found only in Gram negative cells (e.g., Listeria), and found as part of their cell envelope.
- They are released when the bacterial cells die
- exotoxin - a protein secreted by baterial cells into the environment
- enterotoxin - any toxin (endo or exo) that attacks the gut