Helicobacter pylori urease and adhesion proteins

Helicobacter pylori urease and associated membrane/adhesion components are essential virulence factors that enable the bacterium to survive and colonize the harsh acidic environment of the human stomach. Urease is a large, nickel-containing enzyme complex that catalyzes the hydrolysis of urea into ammonia and carbon dioxide, creating a neutralized microenvironment around the bacterium (Mobley et al., 1995). This neutralization is critical for initial survival and subsequent movement through the gastric mucus layer. Complementing this, adhesion components such as BabA (Blood group antigen-binding adhesin) and SabA (Sialic acid-binding adhesin) allow the bacteria to bind specifically to receptors on the gastric epithelium, such as Lewis b and sialyl-Lewis X antigens (Doohan et al., 2021). These interactions prevent the bacteria from being shed during gastric emptying and facilitate the delivery of toxins like CagA into host cells. Because of their central role in pathogenesis, these proteins are primary targets for diagnostic tests like the urea breath test and are being investigated for vaccine development (StatPearls). Pharmacological inhibition of urease, for example by acetohydroxamic acid, can reduce bacterial viability but is often limited by side effects (PubChem). Targeting the adhesion components represents a promising anti-adhesion therapeutic strategy to prevent or clear chronic infections. Overall, these components are fundamental to the progression of H. pylori-related diseases, including chronic gastritis, peptic ulcers, and gastric adenocarcinoma.

Other names

Helicobacter pylori ureaseUrease alpha subunit (UreA)Urease beta subunit (UreB)Blood group antigen-binding adhesin (BabA)Sialic acid-binding adhesin (SabA)Outer inflammatory protein A (OipA)Helicobacter outer membrane protein (HopQ)Adherence-associated lipoprotein A/B (AlpA/B)

Urease inhibitors act by binding to the nickel-containing active site of the enzyme, preventing urea hydrolysis and thus sensitizing the bacteria to gastric acid (Mobley et al., 1995). Anti-adhesion agents work by competitively binding to bacterial adhesins or host receptors to prevent colonization (Doohan et al., 2021).