23. H. pylori Flashcards
Shape and Gram and motility of H. pylori?
G-
Spiral-shaped rod
2-4 polar sheathed flagella
Transmission of H.pylori?
Oral-oral, possible parents-children
2 scientists who discovered H.pylori?
Barry Marshall and Robin Warren
Marshall drank it
Function of urease?
Maintain H.pylori cytosol at neutral pH
What does urease catalyze?
Urea (in gastric juices) to ammonia and CO2
2 purposes of ammonia made from urease rxn?
Removes H+ to form ammonium ions = increases alkalinity
Intracellular amino acid production
Aside from survival, another purpose of H.pylori decreasing pH via urease?
Decreases mucin viscosity = easier to penetrate to reach epithelium
Bacterial oncogene in H. pylori?
CagA (cytotoxin-associated gene A)
What encodes H.pylori T4S?
cag PAI
CagA is associated with H.pylori strains that cause ______ and ______
ulcers and cancer
Why is CagA an oncoprotein?
Ability to induce cell proliferation
What does CagA cause?
Cytoskeletal rearrangements, initation of pro-inflammatory response
Function of VacA?
Kills gastric epithelial cells via vacuole formation, permeability, and apoptosis
Initiaties pro-infalmmatory response
What recruits neutrophils and monocytes that cause tissue damage via ROS release?
Neutrophil-activating protein (NAP)
Function of Cag T4S?
Translocates virulence-associated proteins from bacteria to cytosol of epithelial cells