Helicobacter pylori has elaborated a unique set of virulence factors that allow it to colonise
the stomach wall. These factors include urease, helicoidal shape, flagella and adhesion
molecules. Here we discuss the molecular characteristics and mechanisms of action of the
vacuolating cytotoxin, VacA, and the neutrophil-activating protein, HP-NAP. Their activities
are discussed in terms of tissue alterations, which promote the release of nutrients
necessary for the growth and survival of the bacterium in its nutrient-poor ecological niche.