Bacterial Infections USMLE Step 1 Practice Question
A 49 year old man presents with chronic epigastric pain that improves with meals but recurs several hours later. He has no weight loss or vomiting. Endoscopy shows a duodenal ulcer. Gastric biopsy demonstrates curved gram negative rods. Which of the following properties is most important for this organism’s survival in the stomach?
Answer choices
- AExpression of protein A
- BCapsular polysaccharide
- CAbility to ferment lactose
- DEndospore formation
- EUrease productionCorrect answer
- FProduction of lipopolysaccharide (LPS) with minimal proinflammatory epitopes
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