Bacteriology USMLE Step 1 Practice Question
A 58-year-old female is admitted to the hospital with fever, abdominal cramps, and severe watery diarrhea. The symptoms began one day after attending a banquet. She was treated with ciprofloxacin, but her condition did not improve. PCR amplification and analysis of a gene region in the bacteria isolated from the patient revealed a missense mutation that conferred resistance to ciprofloxacin. The missense mutation is most likely in the gene encoding an enzyme essential for which of the following functions?
Answer choices
- ADNA replicationCorrect answer
- BReduction of folate to tetrahydrofolate
- CPeptide bond formation
- DmRNA translocation on a ribosome
- EFolate synthesis
- FCell wall synthesis via penicillin-binding proteins
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