Final answer:
Helicobacter pylori (H. pylori) is a bacterium that colonizes the stomach lining and causes damage. It produces virulence factors, including the VacA toxin, and modifies its lipopolysaccharides (LPS) to evade the immune system.
Step-by-step explanation:
Helicobacter pylori (H. pylori) is a bacterium that colonizes the epithelial cells lining the stomach. It uses various virulence factors, such as pili for adhesion and urease to neutralize stomach acids, to invade the mucin layer and cause damage to the stomach lining. One of the virulence factors produced by H. pylori is the VacA toxin, which induces vacuole formation in host cells and contributes to tissue damage.
This bacterium is able to evade the immune system by modifying its lipopolysaccharides (LPS) to avoid detection and phagocytosis.