A strain of Staphylococcus aureus acquires resistance to tetracycline and erythromycin simultaneously after exposure to a plasmid carrying a mobile genetic element. This element can move between the plasmid and the chromosome without requiring homologous recombination. What is this mobile element called?
- A Transposon ✓
- B Insertion sequence
- C Integron
- D F plasmid
Correct answer: A. Transposon
Explanation
Transposons are mobile DNA segments that can move from one location to another in the genome without homologous recombination, often carrying antibiotic resistance genes. Insertion sequences are simpler and only encode transposase. Integrons capture gene cassettes but do not move independently. The F plasmid mediates conjugation.
Reference: Jawetz, Melnick, & Adelberg's Medical Microbiology, 28th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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