Bacteriology USMLE Step 1 Practice Question
A 69-year-old, alcohol-dependent male comes to the emergency department because of high fever, chills, and a cough. He says that he has been producing 'lots of thick, bloody, gelatinous mucus' over the past 2 days. Gram staining of the sputum reveals pinkish-red bacilli. Chest x-ray shows consolidation of the upper lobes. Which of the following is found only in microorganisms with this color Gram staining?
Answer choices
- ACell envelope
- BTeichoic acids
- CPeptidoglycan
- DExotoxin
- EPeriplasmic spaceCorrect answer
- FLipopolysaccharide (LPS) in the outer membrane
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